Cattle Practice October 2021

CATTLE PRACTICE VOLUME 29 PART 1

Maintaining cattle health during extreme weather events and disasters:
veterinary advice and tips

Prins, D., The Farm Vet Academy, Greenacre, Bonnybridge, Stirling, Scotland, FK4 1ST

ABSTRACT
The past two decades have seen some extreme weather and disaster situations both in the United Kingdom
and worldwide. In the UK, flooding during storm Desmond, Ciara and Dennis and extreme winter conditions as
a result of “The Beast from the East” and disease such as “Foot-and-Mouth” disease caused severe disruption
to normal work and live in the UK. Similar and even more extreme disasters have been encountered in other
parts of the world. With an indication that climate change might be contributing to both the cause, severity
and number of these events together with disasters caused by human activity, such as hazardous spill, barn
fires and even radioactive fall-out from nuclear plants, it is more than likely that disaster events will be
increasingly encountered in the livestock industry.

Most people instinctively know what to do to keep themselves and their loved ones safe during a disaster.
However, panic, inexperience, lack of authority and involvement of animals might impact greatly on rational
decision making. As livestock veterinarians, both trained in emergency critical care, herd health management
and maintaining and restoring animal welfare, our profession is often at the forefront of disasters that involve
animals. However, as livestock veterinarians we might not be familiar with disaster situations, guidance
of emergency response workers, dealing with large numbers of cattle at the same time and diseases or
contaminations in the aftermath of a disaster situation.

The time to prepare for eventual disasters should be long before they occur. Disaster management
procedures should be written down, kept safe, in a fireproof, easily accessible place and be familiarised
amongst key members of colleagues, staff and emergency responders.

The first step in planning for disasters is to determine what disasters are most likely to occur on the farm or
in the area. Once the risks are known decisions can be made about what type of actions are required during
these disasters. Generally, avoiding the disaster, mitigating its effect if it can’t be avoided and sheltering
animals reduces the effect of a disaster on livestock.

Hazard mitigation is defined as any action resulting in elimination or reduction of the long-term risk to life
and property from hazards. As such the farm or premise should be surveyed to determine the mitigation
procedures that should be followed based on the hazard risk. A list of resources and people should be
developed by the farmer and kept with the important papers. This list should contain emergency phone
numbers, suppliers, truckers, milk bales, and people that can help with the animals.

If a disaster is anticipated, due to weather forecasts or government announcements, the response protocol
should be initiated. Vaccinations should be up-to-date and animal health optimised and arrangements made
to maintain feed and drug supply, milking and milk pick-up. The needs of animals during disasters are given
low priority, but actions required protecting animals, such as sheltering and evacuation, must be done long
before a similar action is taken for humans as such actions require considerable time and physical labour. As
local government and weather forecasts will not recommend actions to be taken regarding animals before
actions are recommended for humans, animals should be protected while it is still safe for people to do so.
Evacuation procedures, places, routes and personnel should be planned. However, not all animals might be
able to be evacuated and owners should decide ahead of time which are the most important ones to save.
Whether to move livestock for shelter or leave them outside will depend on the integrity and location of the
shelter and the nature of the disaster. In some cases, leaving cattle and sheep outside is better than indoors.

The immediate aftermath of the disaster undoubtedly is full of emotion and can be chaotic. But as farm
animal veterinarians, we have the expertise to improve both the situation and animal welfare in coordination
with the emergency workers and cattle farmers. By securing the area, establishing scene safety and assessing
the scene and animal situation, order can be restored by initiating a “Rapid Needs Assessment”. Triage of
animals, anticipated needs, identified deficiencies and vulnerabilities will have to take place to prevent
detrimental shortages, diseases, contaminations and a general decline in animal health. After disasters, local
government usually limits access to disaster areas. Designating veterinarians and farmers as emergency
workers by government solves the problem of who will be responsible for the task of feeding, watering and
milking the animals.

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By planning and initiating preparations to minimise the effect of adverse weather events and disasters on
cattle farms, farm animal veterinarians not only prepare their livestock clients for possible future disaster
situation, they also put themselves in an expert position to liaise between various local authorities, emergency
responders and cattle owners. By doing so, both animal health and welfare will be maintained and emotional
and mental health impact of those involved minimised.

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CATTLE PRACTICE VOLUME 29 PART 1

A behavioural study to evaluate positive welfare in dairy cows

Russell, A.L.1, Randall, L.V.1, Bollard, N.1, Kaler, J.1, Gibbons, J.2, Green, M.1,
1Ruminant Population Health Research Group, School of Veterinary Medicine and Science,
University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD
2Agriculture and Horticulture Development Board, Stoneleigh Park, Kenilworth, Warwickshire, CV8
2TL

Both within the UK and globally, there has been an interactions surrounding access to the novel object
increasing shift to year-round housing of dairy cattle and brush were evaluated. Herd level activity was
(March and others 2014). Over the past decade, monitored including behaviours such as lying and
the evaluation of animal welfare has extended inactive standing, a behaviour linked to boredom.
beyond solely alleviation of negative states, there Behavioural use of the robotic milking machine,
is now increased emphasis that opportunities including unsuccessful milking attempts were
for positive experiences should be considered recorded.
(Yeates and Main 2008, FAWC 2009). Evaluation
of animals’ subjective states is not directly Preliminary analysis shows that all individuals
possible, therefore identifying when animals are interacted with the object within 27.11 hours of
experiencing something they perceive as positive object presentation, (mean (± standard deviation):
and identifying how to offer opportunities for this (220.02 minutes (± 319.04)). The group physically
are problematic. Current housing of dairy cattle interacted with the object for 655.97 minutes (week
paired with the increased societal concern for dairy 1), 327.22 minutes (week 2) and 301.64 minutes
cattle welfare (Cardoso and others 2016, Wolf and (week 3). Percentage of cows which performed self-
others 2016) poses opportunity for investigation grooming during at least one of their interactions
and development of how current housing may offer with the object was 84.38% (week 1), 70% (week
positive experiences. 2) and 86.21% (week 3). The two most frequently
occurring behaviours in response to the object
Opportunities for interest and exploration have were tail wagging (rate per minute, 1.49±0.96) and
been highlighted as possible avenues of positive head and nose contact with the object (rate per
welfare provision (Boissy and others 2007, Mellor minute, 1.99±2.51). Significantly less unsuccessful
and Beausoleil 2015). Exploration has been milking attempts and number of cows scored as
suggested as a valued behaviour (Boissy and others ‘idling’ were found for all weeks the novel object
2007), offering some agency and diversity within was present compared with the weeks prior to and
the environment (Wood-Gush and Vestergaard after presence. Both self-grooming (Zimmerman
1993) conversely with the lack of, being shown to and others 2011, Raspa and others 2020) and
be aversive with possible links to boredom (Wood- tail wagging (de Oliveira and Keeling 2018) have
Gush and Vestergaard 1989). Novel object tests previously been considered to be associated with
have been widely used to evaluate predominantly positive experiences. Preliminary results suggest
fear, but also explorative behaviour, however these that offering environmental diversity, by addition of
tests tend to be conducted for a short period, on a simple novel feature, has the potential to facilitate
isolated individuals in different contexts to their positive experiences in housed dairy cattle.
commercial management. This study evaluated the
behavioural response of a group of commercially REFERENCES
housed dairy cattle through a five week long novel
object test. Boissy, A., Manteuffel, G., Jensen, M. B., Moe, R.O., Spruijt,
B., Keeling, L.J., Aubert, A. (2007) Assessment of positive
A group of 37 adult dairy cows of mixed age emotions in animals to improve their welfare. Physiology and
and stage of lactation, were recruited. Exploration Behavior 92: 375–397
within an extended loafing area containing the Cardoso, C.S., Hötzel, M.J., Weary, D.M., Robbins, J.A., von
novel object (inflated sailing buoy), evaluation of Keyserlingk, M.A. (2016). Imagining the ideal dairy farm.
physical interaction with the object, self-grooming Journal of Dairy Science 99(2): 1663-1671
and use of an established automatic brush were Council, F.A.W. (2009) Farm animal welfare in Great Britain:
conducted using video recordings. A detailed past, present and future. Farm Animal Welfare Council.
ethogram of cow behaviour was used to evaluate de Oliveira, D., Keeling, L.J. (2018) Routine activities and
cows’ initial behavioural response to the novel emotion in the life of dairy cows: Integrating body language
object. Positive and negative social behavioural into an affective state framework. PLoS One,13(5): e0195674.
March, M.D., Haskell, M.J., Chagunda, M.G.G., Langford,
F.M., Roberts, D.J. (2014) Current trends in British dairy

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management regimens. Journal of Dairy Science, 97(12):
7985–7994. https://doi.org/10.3168/jds.2014-8265
Mellor, D.J., Beausoleil, N.J. (2015) Extending the ‘Five
Domains’ model for animal welfare assessment to incorporate
positive welfare states. Anim. Welf. 24(3): 241
Raspa, F., Tarantola, M., Bergero, D., Nery, J., Visconti, A.,
Mastrazzo, C.M., Cavallini, D., Valvassori, E., Valle, E. (2020)
Time-Budget of Horses Reared for Meat Production: Influence
of Stocking Density on Behavioural Activities and Subsequent
Welfare. Animals 10(8): 1334
Wolf, C.A., Tonsor, G.T., McKendree, M.G.S., Thomson, D.U.,
Swanson, J.C. (2016) Public and farmer perceptions of dairy
cattle welfare in the United States. Journal of Dairy Science,
99(7): 5892-5903
Wood-Gush, D.G.M., Vestergaard, K. (1989) Exploratory
behavior and the welfare of intensively kept animals. Journal
of Agricultural Ethics 2(2): 161–169
Wood-Gush, David G.M., Vestergaard, K. (1993) Inquisitive
exploration in pigs. Animal Behaviour 45(1): 185–187
Yeates, J.W., Main, D.C. (2008) Assessment of positive
welfare: a review. The Veterinary Journal 175(3): 293-300
Zimmerman, P. H., Buijs, S. A. F., Bolhuis, J. E., Keeling, L.J.
(2011) Behaviour of domestic fowl in anticipation of positive
and negative stimuli. Animal Behaviour 81(3): 569-577

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CATTLE PRACTICE VOLUME 29 PART 1

The Animal Pathway Initiative; what is it and how will it affect me and
clients

Seals, M., Defra, Area 5C, Nobel House, 17 Smith Square, London, SW1P 3JR

PATHWAY #1: ANNUAL HEALTH AND The farmer and their vet will agree and prioritise
WELFARE REVIEW a series of recommended actions after a detailed
As a first step on the Animal Health and Welfare discussion about the farm, its management
Pathway, Defra will fund a yearly visit from a vet, and any known health and welfare concerns or
(who may be leading a team or vet-led team.) In the opportunities. Where a health and welfare plan
first instance this funding will be available for three exists for a farm, this will be the initial place to start
years. The proposal co-designed with the industry discussions between the farmer and their vet, with
and our veterinary species groups is for an annual the review building upon those areas covered in
review that takes approximately 2-3 hours of the existing health and welfare plan.
veterinary time, but will be flexible. This will launch
as a voluntary initiative but further consideration The review will therefore recommend actions
of how to reach all farmers and establish a national to improve livestock health and welfare, by
picture of health and welfare through universal agreement between the farmer and the vet. This
participation will require a mandatory approach will allow year on year progress to be measured
in the future. If adopted, this would require new with opportunities of support available to the farm
legislation. Building on the review, next steps will through the associated Pathway grants and training
include species specific national endemic disease schemes.
control programmes and access to a wide-ranging
set of capital grants. Flexibility will be built into the review process to
meet the needs of individual farmers. This means
This Annual Health and Welfare Review will help that although there will be some common aspects,
raise awareness of endemic diseases and support they won’t look the same on every farm – this will
healthy livestock, promote responsible use of particularly be the case for biosecurity and for the
veterinary medicines, improve welfare and increase specific advice received by the farmers. The review
sustainable farm productivity, building on the will aim to add value to existing practices and
strong relationships that exist between farmers complement existing assurance schemes, while
and vets. It will also collect some key industry minimising duplication of effort and administrative
data needed to promote and support the efforts burden.
of English farmers to continually improve animal
health and welfare within sustainable faming Summary of the review
businesses. The following elements are relevant to all
commercial pigs, sheep, beef, and dairy keepers:
Action taken as a result of the Annual Health
and Welfare Review will also contribute to 1. Collection of data for benchmarking against
government commitments on the responsible use the national herd/flock picture and to mark
of antimicrobials, as set out in the UK Anti-Microbial progress on the farm.
Resistance 5-year National Action Plan and support
environmentally sustainable livestock farming and 2. A biosecurity review at a level of detail
food production. appropriate for the farm and recommend
priority areas for action to improve
The Annual Health and Welfare Review will biosecurity. This includes training,
include diagnostic testing for priority diseases or capital investment, and changes to farm
conditions, and farm bespoke advice on health, management practice.
welfare, biosecurity and the responsible use of
medicines. As part of the review, farmers and 3. A review of medicines usage on farm and
vets will share data which will be used to better discussing responsible use of medicines,
understand the health and welfare of the national including antibiotics and vaccinations. This
herd and flock. It will be made clear that the data includes uploading medicines usage to
collected will only be used to help improve animal relevant central e-medicines book/hub. The
health and welfare on farm and not used by Defra review would also review opportunities for
for any regulatory or inspection activity, but should other health and welfare actions such as
include benchmarking. pain management.

4. Recommendations and monitoring, which
will include a report from the review setting

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out specific priority recommendations to PATHWAY #3: WELFARE GRANT SCHEMES
improve health and welfare, advice about AND TRAINING
ongoing monitoring to help identify how One element of the Review will be signposting
things are changing through the year, advice farmers to other support that might be available
on how to record data as part of the review to them to tackle health and welfare issues, such
and signposts to further support to help with as grants, training or industry initiatives. This may
making changes over time. include veterinary support for grant applications
for equipment, projects and skills training that
PATHWAY #2: ENDEMIC DISEASE CONTROL can address health and welfare issues on farm.
Testing for disease These are due to be available from Autumn 2022.
Testing will initially focus on identifying priority For example, lameness in dairy cows is a priority
endemic diseases or conditions, in cattle, pigs, issue for dairy cows that could be prioritised for
and sheep. These priorities have been co-designed funded support through provision of appropriate
with industry, to ensure focus on health issues that equipment and skills training for both hoof care
matter to farmers, as well as delivering benefits for and mobility scoring. Access to capital grants will
the public. be made widely available.

For cattle, we will initially test for Bovine Viral Further grants may become available from
Diarrhoea (BVD), which is estimated to cost the 2024 for farmers who want to undertake further
industry around £60 million per annum and enhanced actions to improve welfare.
increases greenhouse gas emissions from cattle
through the increased waste associated with
disease. In pigs, our initial focus will be on Porcine
Reproductive and Respiratory Syndrome virus
(PRRS), which is estimated to cost the industry
around £52 million per annum and increases
antibiotic use. The approach could later be applied
to other endemic diseases such as swine dysentery.
For sheep, testing will start with parasitic resistance
to anthelmintic treatments (drench testing),
because this affects productivity and increases
greenhouse gas emissions on a national basis.

The diagnostic testing aspect of the review will
vary by species.

Summary of endemic disease control
The initial focus for testing for each species will be:

1. Pigs - testing for Porcine Reproductive and
Respiratory Syndrome virus, with follow-up
advice for those with a positive result.

2. Sheep - testing for anthelmintic resistance,
in the flock, with recommendations on how
to use anthelmintics appropriately, based
on these results.

3. Beef and dairy - testing for Bovine Viral
Diarrhoea, with follow-up advice for those
that have a positive result. E.g. Tissue test
for BVD on EVERY new born calf in England
in first 12 months of Pathway-fully funded.

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Action plans to improve dairy herd health: examples and discussion

Breen, J., Moorhouse, J., Cooper, R., Roberts, J., Baird, G., Husband, J., Map of Ag, Suite 1A,
Cumbria House, Gilwilly Road, Penrith, Cumbria, CA11 9FF

ABSTRACT
Dairy farms aligned to contracts such as Arla 360 and the Sainsbury’s Dairy Development Group are
monitored to high standards of dairy herd health and are required to have an independent audit from an
independent veterinary surgeon with demonstrable expertise in dairy herd health at least annually. Targets
and intervention levels are set for all areas of dairy herd health and performance, particularly for those areas
considered to be a “brand risk” such as calf mortality, the prevalence of cows that are lame, increased rates
of clinical mastitis and increased rates of culling and losses in early lactation. In addition, the focus on calf
health, foot health, production diseases such as displaced abomasum events and udder health are all likely
to impact on herd antibiotic use, which continues to be very important to high welfare schemes alongside
health and sustainability.

Herds that fall outside current scheme targets are required to engage with their veterinary surgeon and
produce appropriate action plans to address non-compliances with the particular area(s) of herd health
and these action plans are used as evidence that the herd is working towards improving herd health and
welfare. The independent veterinary advisor is tasked with providing some key pointers to both farm and
the veterinary surgeon in practice during the audit as well as providing an opinion on the suitability of action
plans that are produced.

This workshop aims to provide veterinary surgeons with case material to illustrate appropriate approaches
to creating action plans to address poor performance in areas including calf health, foot health and udder
health, as well as offering constructive feedback on plans which are likely to be unsuitable. Action plans will be
discussed in the light of the latest evidence from research wherever possible and attendees are encouraged
to bring along milk recording/on farm software data and pictures to illustrate herd management to allow
specific points to be raised and discussed.

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On farm testing and selective treatment of clinical mastitis – where is the
science, and is it a good idea for my clients?

Plate, P., Royal Veterinary College, Regional Veterinary Centre – South of England, Stinsford
Business Centre, Kingston Maurward College, Dorchester, DT2 8PY

ABSTRACT
The workshop is an interactive session, first summarising the current scientific knowledge on on farm testing
and selective treatment, followed by discussing practical aspects of introducing and supporting the concept
on farms.

The method of using antimicrobials only for mild/moderate mastitis cases caused by gram positive
organisms has been used in many countries for several years, and in a drive to reduce anti-microbial usage is
becoming increasingly popular in the UK. A variety of test kits which can be used on farm are now available
(e.g. Vetorapid, Minnesota easy culture, other bi-, tri- and quad-plates, Petrifilm, MastDecide), and the
advantages and disadvantages of the different systems are discussed with regards to accuracy, practicality/
ease of use, speed, detail, operator and environmental safety, availability and cost etc. New concepts of test
kit development are outlined. Different farms may prefer different test kits, however, emphasis will be given
to their role in facilitating individual treatment decisions only and not replacing specialised laboratories which
can identify pathogens up to species level and assist in trouble-shooting causes of mastitis. The validity of the
concept is outlined and concerns about delays in treatment, potential difference in cure rates, accuracy of the
results (potentially resulting in under or over treatment), chronic or non-responsive gram-negative pathogens
are addressed. An economic assessment for various farms and scenarios is also given.

The second part deals with practicalities of introducing and supporting the method on farm, starting with
client selection. Criteria for suitable clients include the ability to take sterile milk samples and a generally
positive attitude to hygiene and cleanliness, a clean lab area away from the parlour and milk tank, a stable
staffing situation with dedicated, forward thinking people, a reasonable proportion of mastitis cases caused
by Gram negative bacteria, and the willingness to apply preventive measures before opting for modifying
treatment decisions. Continuous coaching by the farm vet is vital, and part of the vet’s advisory role is to
explain to certain clients why the method is not suitable for them, but support those who may benefit. As
many veterinary practices are now using the method in various forms knowledge exchange and the discussion
of real cases and different concepts is intended to form a major part of the workshop.

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UK dairy farmers’ enthusiasm for the QuarterPRO udder health initiative

Breen, J.1, Green, M.1, Hague, J.3, Leach, K.2, Manning, A.2, Bradley, A.1,2, Hartley-Byng, J.3,
Armstrong, D.3,
1University of Nottingham School of Veterinary Medicine and Science, University of Nottingham
Sutton Bonington, Leicestershire, LE12 5RD
2Quality Milk Management Services Ltd, Cedar Barn, Easton Hill, Easton, Wells, BA5 1DU
3Agriculture & Horticulture Development Board, Stoneleigh Park, Kenilworth, Warwickshire, CV8
2TL

ABSTRACT
The QuarterPRO approach to ongoing udder health improvement, recently launched by the Agriculture and
Horticulture Development Board (AHDB), is easily accessible to all dairy farmers with milk recording data
and clinical mastitis records. It involves three steps: 1) analysis of records, using an automated “Mastitis
Pattern Analysis Tool” (MPAT), which categorises the epidemiological pattern as Environmental Dry Period,
Environmental Lactation or Contagious; 2) deciding on the most relevant interventions and 3) implementing
changes. These steps can be presented as: Predicting the epidemiological “pattern” of mastitis for a herd,
Reacting using pattern specific resources to identify relevant management changes, and Optimising ongoing
mastitis control by implementing a specific action plan and reviewing records on a quarterly basis, hence the
name “QuarterPRO”.

The QuarterPRO initiative was launched by AHDB in Spring 2020. A series of 24 farmer workshops were
attended by a total of 335 delegates. The original schedule was for 20 workshops, and popular demand
led to a further four being organised. Sixteen workshops were held in England, three in Wales and five in
Scotland. A sixth Scottish workshop was cancelled due to the Coronavirus COVID-19 outbreak. Registrations
were received from 408 individuals, representing 277 farms and 12 other related businesses. Attendance rate
was 82% of registrations. In addition, five separate workshops were held for vets and advisers, with a total of
53 attendees.

Farmers were invited to provide their herd mastitis data in advance, preferably in CDL (common data layer)
format from a milk recording organisation (subject to appropriate GDPR procedures). Where data quality
allowed, a herd mastitis “pattern” report was produced for each attendee. Where full milk recording data
was not available, or clinical data was of poor quality, or lacking, manual calculations were made when
possible, to give a suggestion of the relative importance of new infections from the dry period, and lactation.
Individual farm reports were presented to the farmers, with discussion around data quality and the value
of good recording. Farmers separated into groups according to their predominant herd mastitis pattern
(environmental dry period, environmental lactation, or contagious) and discussed possible control measures
relevant to their specific pattern, and feasible for their respective herds. Discussions were clearly animated
and focussed, with good participation and exchange of ideas. Feedback from the groups was co-ordinated
by the group facilitator. Each farmer left the meeting with the appropriate resource booklet for their pattern.
Veterinary/adviser workshops ran on similar lines, with the addition that delegates were encouraged to bring
their own data, and shown how to analyse this using the MPAT.

Feedback from all the workshops was very positive, especially the fact that the information was “specific”
and “tailored to our individual circumstances”. Relevance to the business was rated as “Good” by 44% and
“Excellent” by 52% of farmers. Fifty-six percent went home “definitely” resolving to “do something with the
information learned”, and 35% were “likely” to do so. Farmers recorded very specific practical areas to attend
to, e.g. “increase loafing area from cubicles”, “drying off procedures”, “pre-milking routine”.

The success of these launch workshops suggests that the QuarterPRO approach should be popular with a
wider group of farmers, and would encourage use of existing farm data, and improvement of mastitis records.
As a result, more relevant, farm specific mastitis control actions are likely to be taken. The cyclical nature of
the approach fosters regular review and ongoing improvement would be expected.

Training videos to guide advisers and farmers through the QuarterPRO process, and the tools and resources
required, are available at the QPRO website https://ahdb.org.uk/quarterpro. Accreditation for veterinary

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surgeons providing support for the QuarterPRO process is available through BCVA, in a similar way to the
National Johne’s Management Plan and Register of Mobility Scorers. As a ‘next step’, or for more detailed
investigations, farmers should still be signposted towards the AHDB Mastitis Control Plan, recognised as the
gold standard approach to improving udder health across the UK dairy industry.

Ending with the words of two participating farmers:
(QuarterPro) “identified our source of mastitis, gave us tools to monitor and information on how to combat
it”.
“A small amount of time inputting data gets results to enable you to better your herd health”.

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Using thoracic ultrasound (TUS) in combination with a consultative
approach to monitor and benchmark the respiratory and general health
of cattle youngstock on UK farms – using a UK case study example

Baxter-Smith, K.1, More, J.2,
1MSD Animal Health, Walton Manor, Walton, Milton Keynes, MK7 7AJ
2Galloway Vet Surgery, The Old Workshop, Gas Lane, Kirkcudbright, DG6 4HX

ABSTRACT
There are many different methods used for diagnosing respiratory disease in cattle youngstock by vets
and farmers, however, aside from Post Mortem, there is not one ‘gold standard’ technique and it has been
reported that farmers often underdiagnose or are late to detect these respiratory cases (Timset and others
2009, White and others 2009), which in turn leads to reductions in productivity and welfare.

Thoracic ultrasound (TUS) has been reported as a sensitive method of detecting bovine respiratory disease
(Rabeling and others 1998) and has been described as a simple, practical, calf-side diagnostic tool which can
be used in calves from 1 week of age and upwards (Ollivett and Buczinski 2016).

This technique can be quickly learned, particularly by vets already skilled in using ultrasound, and requires
the same equipment as obstetric scanning (Pardon and others 2019) and once practiced at the technique, it
can be performed in under 1 minute per calf.

Different scoring systems have been developed and in the authors experience, there is not one that appears
to be superior, however it is important that the operator maintains consistency when scoring and reporting
lesions within and between calves.

There are many opportunities for using this technique in practice when used in combination with a
consultative approach to youngstock. TUS can be applied successfully to improve youngstock health in

several ways such as comparing farmer-recorded treatment data with actual disease levels detected by
TUS, screening heifers at weaning for suitability to be included in the future milking herd, benchmarking
farms to encourage improvement in management practices and to assess success of prevention programs
by scanning a cohort of calves of the same age and management system before and after the proposed
prevention program change. The ability to demonstrate to the farmer in real time the images of lungs of
healthy vs diseased calves cannot also be underestimated.

Work has been undertaken in the UK to assess the suitability and practicality of using this technique to
benchmark management changes suggested after running on-farm youngstock audits using the MSD Calf
Health Checklist on 6 large dairy farms with a total of 347 calves scanned using TUS.

Of 347 ultrasonographic examinations, 53 (15.3%) were classified as abnormal and 294 (84.7%) as normal.
Of the 53 calves classified as abnormal, only 13 (24.5%) were treated by the farmer, and of the 294 classified
as normal, 22 (7.5%) were treated by the farmer.

Results obtained in this study suggested a link between high youngstock management scores and lower
levels of lung lesions identified by TUS. This study also found a discrepancy between levels of pneumonia
measured by farmer-recorded treatments and lung lesions suggestive of pneumonia when the same calves
were evaluated using TUS. Conversely, nearly 8% of calves had received an antibiotic treatment for pneumonia
but had no lung lesions present on TUS. This could represent an opportunity for improved BRD diagnostics
and reduced unnecessary antibiotic use.

Additionally, one farm that stopped using pneumonia vaccine was found to have much higher levels of
pneumonia in the subsequent cohort of unvaccinated calves. (More 2019 + unpublished data)

REFERENCES Veterinary Record 185(4): 109 10.1136/vr.105238
Rabeling, B., Rehage, J., Döpfer, D., Scholz , H. (1998)
More, J.B. (2019) On farm use of Bovine thoracic Ultrasonographic findings in calves with respiratory disease
ultrasonography (TUS) for respiratory disease detection. Veterinary Record 143: 468-471
Poster presentation, BCVA Congress 2019. Cattle Practice Timsit and others (2009) Rational treatment of respiratory
27(2): 113 disorders in young bulls, at fattening units in France.
Ollivett, T.L., Buczinski, S. (2016) On-Farm Use of Proceedings EBF, Marseilles
Ultrasonography for Bovine Respiratory Disease. Veterinary White, B.J., Renter, D.G. (2009) Bayesian Estimation of the
Clinics: Food Animal Practice 32(1): 19–35 Performance of Using Clinical Observations and Harvest Lung
Pardon, B., Buczinski, S., Deprez, P.R. (2019) Accuracy Lesions for Diagnosing Bovine Respiratory Disease in Post-
and inter-rater reliability of lung auscultation by bovine weaned Beef Calves. J. VET. Diagn. Invest. 21(4): 446–53
practitioners when compared with ultrasonographic findings
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Managing dairy cow lameness

Atkinson, O., Dairy Veterinary Consultancy Ltd, Park View Business Centre, Combermere,
Whitchurch, Shropshire, SY13 4AL

INTRODUCTION A Mobility Steering Group already exists for
Dairy cow lameness is at the top of many people’s the dairy industry, with representatives from
agendas right now. the farming, veterinary, farm assurance and
academic sectors. The long-term objective of the
Cattle lameness (and digital dermatitis) recently Mobility Steering Group is to improve lameness
topped the list of diseases of greatest concern for management on-farm. The group has adopted the
farmers and vets in the 2021 Ruminant Health and following goals:
Welfare survey (Miller 2021). This is a big issue,
which costs the industry an estimated £1.2 million 1. Continuous improvement in the mobility
per day (AHDB 2020). In addition, the reputational of cows in UK dairy herds leading to less
damage to the dairy sector is significant, and it is an lameness, better cow welfare, more
animal welfare problem. productive cows and less antibiotic use.

In 2020, an AHDB-funded participatory 2. Reduce prevalence of cows with Mobility
policy development project, undertaken by the Score 2 to less than 10% by 2030.
Royal Agricultural University, brought together
stakeholders across the dairy industry to consider 3. Zero tolerance of cows with Mobility Score
how lameness can be reduced (Williams van Dijk 3 on all dairy farms from 2025 (unless
2020). Amongst the policy proposals, the farmers, treated and recovering).
farm assurance schemes and milk processors
recommended that vets should be leading in efforts 4. All dairy cattle should have a life worth
to help farmers reduce lameness. They should do living with good mobility throughout that
this by providing training and advice to farmers. life.
In particular, the suggestion was that the ability
to deliver the Healthy Feet Programme should be Again, practicing vets are seen as integral to these
a standard requirement for all vet practices which efforts and achieving these goals.
provide services to dairy clients.
On a positive note, considerable progress has
EXISTING SITUATION been made in improving the understanding of
There are several different lesions which are lameness over the past 15 years. There is greater
very common in UK dairy cows, and the causes awareness of lameness among farmers and
are diverse. Managing lameness in dairy herds vets. However, lameness prevalence is widely
is complex but possible. Best current scientific underestimated by farmers, particularly where
estimates of prevalence of lameness in the accurate whole herd mobility scoring is not done
national dairy herd is around 30% (Griffiths and by an independent and trained person (Atkinson
others 2018, Randall and others 2019). This means and others 2017).
around 600,000 cows are experiencing discomfort
associated with lameness every day within circa The Register of Mobility Scorers (www.roms.org.
10,500 UK dairy herds. Criticism for this problem uk) lists 396 trained mobility scorers in UK. These
may certainly be levelled at the industry. are mainly vets and veterinary para-professionals.
Each member must first attend an approved training
The strategic relevance of lameness arises from: course, then re-register annually and demonstrate
• Economic losses. competence by passing an online assessment of
• Impact on production efficiency and staff scoring, using video clips.
time resources.
• Welfare implications of lameness, Over 180 Mobility Mentors have been trained
particularly chronic lameness. and over 300 farms registered on the AHDB Healthy
• Industry image and reputation, in the eyes Feet Programme (https://ahdb.org.uk/knowledge-
of the consumer. library/introduction-to-the-healthy-feet-
• Responsibility to reduce reliance on programme). Mobility Mentors (MMs) are mainly
antibiotic use. experienced dairy vets (plus some professional
foot trimmers) who have reached a higher ability
to help farmers reduce lameness through training
and the adoption of the Healthy Feet Programme.

The Healthy Feet Programme is evidence based

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CATTLE PRACTICE VOLUME 29 PART 1

and has been developed through many years of REFERENCES
research. Farms engaging in the programme have
shown a relative reduction in lameness by 22% AHDB (2020) What is the best way to express costs of
within 12 months, on average (Atkinson and others lameness? https://ahdb.org.uk/news/what-is-the-best-way-
2017). The evidence base for managing lameness to-express-costs-of-lameness. Accessed 9/6/21.
has been added to significantly in the past 5 years, Atkinson, O., Fisher, G., Cross, K. (2013) Cattle Mobility:
in particular following the AHDB-funded lameness changing behaviour to improve health and welfare and
research partnership led by Nottingham University. dairy farm businesses. http://www.reaseheath.ac.uk/
wp-content/uploads/2014/02/Cattle-Mobility-Final-report-
THE NEXT STEPS December-2013.pdf. Accessed 9/6/21.
More rapid and widespread improvements will Griffiths, B.E., Grove White, D., Oikonomou G. (2018) A
require a compelling and powerful response from Cross- Sectional Study Into the Prevalence 2 of Dairy Cattle
the whole industry’s and vets included. Benefits Lameness and Associated Herd-Level Risk Factors in England
from the Healthy Feet Programme (HFP) have so and Wales. Front. Vet. Sci. 5: 65. doi: 10.3389/fvets.2018.0006
far reached only a tiny proportion of the national Miller, N. (2021). Ruminant Health and Welfare Report: Cattle
dairy cow population. and sheep health and welfare priorities – a ‘grassroots’ survey
across the four nations of the UK. Report can be downloaded
To help address this, the HFP has been developed from www.ruminanthw.org.uk. https://ruminanthw.org.
and improved during 2020/21 in four strategic uk/wp-content/uploads/2021/05/Cattle-and-sheep-HW-
areas: priorities-survey-May-2021-FINAL.pdf. Accessed 9/6/21.
Randall, L.V., Thomas, H.J., Remnant, J.G., Bollard, N.J.,
1. Greater support for the Mobility Mentor Huxley, J.N. (2019) Lameness prevalence in a random sample
network, including a programme of CPD for of UK dairy herds. Veterinary Record: first published as
current MMs. 10.1136/vr.105047
Wiliams van Dijk, L. (2020) Participatory Policy Development
2. New opportunities for others to become a with farmers, farm assurance schemes and milk processors.
Mobility Mentor, including via a modular Report for AHDB by the Royal Agricultural University and Bos
training route. International Ltd.

3. Development of “HFLite”, a quicker and
simpler intervention which reduces the
barrier for farms (and MMs!) to take the
first step for better lameness management.

4. Development of a framework for HFP
Farmer-Led Action Groups, facilitated
by MMs; recognising that many farmers
often prefer to learn from each other’s
experiences rather than didactic teaching.

The workshop at BCVA Congress (2021) will help
farm vets understand their own role in tackling
lameness effectively, with their clients. It will
look at how to engage farmers; how to go about
investigating lameness methodically, and how to
market professional services and expertise in this
area, despite sometimes low personal confidence
in individual foot care or hoof trimming. Delegates
will be able to discuss their own past experiences
- their successes and their frustrations. They will
be able to learn about being a Mobility Mentor,
and if this could be something for them and their
practice.

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Clostridial diseases and diagnostics

Otter, A., APHA Shrewsbury, Kendal Road, Shrewsbury, SY1 4HD

ABSTRACT
Clostridial bacteria are environmental organisms which have a widespread distribution. They are also
commonly identified within the alimentary tract of animals and humans as part of the normal enteric flora.
The proliferation of these bacteria within the intestine of animals after death can result in spread throughout
carcases, and is responsible in part for the autolysis of carcases, and can affect the identification of specific
pathology associated with other diseases. Hence the examination of fresh carcases postmortem, to identify
specific pathology, and the collection of suitable samples for laboratory tests, are essential when trying to
establish a definitive diagnosis.

A range of different clostridial diseases is recognised in cattle and most of these have the potential to
cause significant losses, sometimes within a very short period. The pathogenesis of most of the diseases is
associated with the production of toxins, and it is the detection of the toxins, and/or the bacteria, together
with the specific gross pathology, and in some diseases the specific histopathological features, which is
necessary.

The clostridial diseases should be considered as three types; the enterotoxaemias and other alimentary
tract infections; the histotoxic diseases; and the neurotoxic diseases. Enterotoxaemias are recognised in
different farm animal species, and in humans, and are caused by Clostridium perfringens. C. perfringens
produces several soluble protein substances which have been shown to produce toxic effects in vitro and
in vivo. It is the tissue damage caused by these toxins which results in the clinical signs and characteristic
pathology. The distinguishing feature of enterotoxaemias is that the toxins are produced within the intestine
of infected animals and subsequently escape into the circulation, resulting in disease manifestations remote
from their site of production.

Since C. perfringens is a common inhabitant of the alimentary tract of animals, the detection of the
organism alone, or the identification of the toxins produced by the bacteria, at postmortem examination,
is not necessarily of pathological significance. The diagnosis of disease requires the identification of the
characteristic pathology in addition to the specific toxins. As the toxins are liberated chiefly within the distal
small intestine, sampling from this site is recommended for laboratory testing, but in addition, to establish
a diagnosis in cattle, histopathology on the brain is required as it is the neuropathological lesions which are
diagnostic.

The histotoxic diseases include clostridial myositis (‘blackleg’), malignant oedema (‘gas gangrene’),
infectious necrotising hepatitis (‘black disease’) and bacillary haemoglobinuria. They are caused by Clostridium
chauvoei, Clostridium septicum, Clostridium novyi and Clostridium haemolyticum, respectively. As with the
enterotoxaemias, these have characteristic pathological features which can easily be missed in carcases
which are autolysing, and although the pathogenesis involves toxin production it is the identification of the
lesions and the specific causative bacteria which is diagnostic.

Tetanus and botulism are neurotoxic diseases caused by Clostridium tetani and Clostridium botulinum,
respectively. Both are paralytic diseases, and similar to most other clostridial diseases, have a high case
fatality. In most cases a diagnosis is based on the clinical signs, a history consistent with potential exposure
to the bacteria, and in some circumstances, postmortem examination to rule out other diseases as in neither
are there characteristic gross pathology lesions or histopathological features.

Although the use of clostridial vaccines is commonplace on many sheep and goat farms in the UK, there
is much more limited vaccination practiced in cattle herds, despite there being good commercial vaccines
available against most of the diseases.

This workshop will discuss the principal features of the clostridial diseases of cattle, the recommended
approach to establishing definitive diagnoses, and the potential pitfalls which practitioners should avoid.

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Farm Vet Champions Workshop – I’ve signed up but what are the next
steps?

Lovatt, F., RCVS Knowledge Farm Vet Champions Clinical Lead; Flock Health Ltd, Egglesburn Farm,
Eggleston, Barnard Castle, Co Durham, DL12 OBD

ABSTRACT
As antimicrobial resistance does not respect country borders or species barriers, it is all of our responsibility,
as vets within the farming community, to promote responsible antimicrobial use. We all have an active role to
play in managing antimicrobial use for the benefit of animals, people and society.

We are totally delighted that you have signed up as a Farm Vet Champion and we look forward to learning
from you and with you as together we ensure optimum antibiotic stewardship throughout the UK livestock
industry.

This workshop will be used to explore ways to encourage each other to access and apply the Farm Vet
Champion CPD material and to set ourselves goals that are SMART – that is specific, measurable, achievable,
realistic and timely.

We will be considering how we can practically apply Plan Prevent Protect principles in different aspects of
our daily cattle work with very specific and relevant examples.

At an individual level, vets make a real difference on farms, consultation by consultation and the Farm Vet
Champions material focuses on the precise point that medicines are prescribed on farms. However, vets
do not work in isolation and are part of a larger community within the practice team and at both regional
and national levels. We will also explore ways of building the veterinary team community to champion best
practice principles at all levels – in the practice, with clients and alongside colleagues.

Farm Vet Champion CPD material and further information can be accessed at rcvsknowledge.org/
farmvetchampions.

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Pro-active herd fertility

Smith, R., Department of Livestock and One Health, Institute of Infection, Veterinary and Ecological
Sciences, University of Liverpool, Leahurst Campus, Neston, Cheshire, CH64 7TE

ABSTRACT
Recent practitioner-based research has indicated that farmers most value vets they perceive to be pro-active
with a holistic, problem solving, approach to herd fertility. Interviews with vets have also indicated barriers
to engagement and the pro-activity farmers seek. The workshop will present and explore this research and
elicit the experience of the participants to co-create an approach to herd fertility addressing these issues. It
will consider what pro-activity means, how to be perceived as pro-active. Issues to consider to create a plan
to improve fertility over the short, medium and long term will be discussed and scoped with the participants.
The overall aim will be to identify how vets can engage farmers to improve fertility to provide both farm and
veterinary business sustainability.

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Defining proactivity and quantifying veterinary fertility input and value
on UK seasonally calving dairy herds

Giles, G., Giles & Parsons Farm Vets, West Roose, Otterham, Camelford, PL32 9YP

ABSTRACT
In the UK there is a paucity of work that examines farmer perceptions of veterinary fertility services for
block calving dairy herds to the author’s knowledge. Anecdotally block calving dairy herds frequently look
to other countries such as Ireland and New Zealand that have a greater focus on seasonal calving dairying.
Block calving herds in Britain make up around 19% of dairy herds (CHAWG 2018), equating to around 2,148
producers.

A gap in the literature is to evaluate the current level of fertility intervention being delivered to these
seasonally calving dairy farmers and to gather information on client perceptions of veterinary fertility
intervention. This will enable the farm animal veterinary profession to review the current level of support to
these clients and decide where improvements could be made.

The aims of the project were therefore to:
i. quantify the current provision of veterinary fertility services in seasonally calving UK dairy herds.
ii. quantify how seasonally calving herds perceive and value their current veterinary input into fertility.
iii. explore how seasonally calving dairy farmers interpret the word ‘proactive’ in the context of veterinary
involvement in delivering fertility services.
iv. quantify what barriers currently exist from the farmers perspective that decrease the amount of
preventive fertility involvement vets have on farm.

A survey was developed which was available in both hard copy and electronic format. It took approximately
10 minutes to complete and it was advertised through veterinary practices, breeding companies, online
farming forums, sales representatives and discussion groups. In addition to the questionnaire, 12 telephone
interviews were performed in order to explore the concept of proactivity and to find barriers that exist from
the farmers perspective that reduce the amount of proactive work that vets do on their farms.

The results showed that the three most commonly reported areas that vets were involved in fertility in
these herds were treatment of non-cycling cows, pregnancy dignosis and designing vaccination protocols.
The median 6 week in calf rate for all respondents was 75%, however 19% of farmers did not know what their
6 week in calf rate was. The median empty rate was 11%, with 11% of farmers stating that they did not know
what their empty rate was at the end of the breeding season. Proactivity featured in the top three answers
for the questions ‘why farmers use their current veterinary practice’ and ‘why they like their current vet’. High
quality of service, vet knowledge and approachability were also highly rated qualities. Proactivity was defined
as actions initiated by the veterinarian and examples included doing data analysis before a visit, following up
on vaccination programmes and finding alternative ways to engage with clients. Barriers that reduced the
amount of involvement that farmers had with their vet included a belief from some farmers that their vet was
not interested in their system and a farmer perception that their vet lacked experience in dealing with other
similar dairy farms.

KEYWORDS: Seasonal calving, dairy herds, proactivity, veterinary input

REFERENCES

CHAWG (2018) Fourth Report GB Cattle Health and Welfare
Group [Online]. Available at https://projectblue.blob.core.
windows.net/media/Default/Beef%20&%20Lamb/CHAWG/
CHAWG-Fourth-Report-2018.pdf [Accessed 15.09.2021].

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Fertility data quality assessment

Reynolds, J., Hudson, C., University of Nottingham, School of Veterinary Medicine and Science,
Sutton Bonington, Loughborough, LE12 5RD

ABSTRACT
Data stored in dairy herd management software is often analysed by clinicians and researchers without data
quality assessment. However, assessment of the likely quality of recorded data is a critical step prior to data
analysis to maximise accuracy and reliability of conclusions drawn from data. As an initial step in a fertility-
related research project, novel measures of data recording quality were developed and applied; metrics
were designed to detect datasets with missing event data and physiologically implausible data. Measures
developed can be summarised over any time-period and include:

• Proportion of lactations ending with a calving date where no insemination is recorded 270-300 days
earlier, designed to detect the under-recording of inseminations.

• Proportion of inseminations with unresolved outcomes, developed to detect inaccuracy in either
subsequent pregnancy diagnosis (PD) or calving event recording.

• Proportion of lactations with no next calving date and no exit date recorded.
• Proportion of lactations with physiologically plausible calving interval (CI) (300-730 days between

calving events), developed to detect inaccuracy of calving event recording.
• Proportion of inseminations with a successful outcome. This metric is designed to detect herds with

a conception rate that is higher than physiologically plausible for a dairy herd (likely to reflect under-
recording of inseminations).
• Proportion of lactations where a “do not breed” event is recorded prior to the voluntary wait period,
and proportion of exits with a corresponding “do not breed” event recorded at least 10 days before
exit; both designed to detect recording of cows marked for culling and not eligible for insemination.

Inaccuracy in insemination recording impacts both submission and conception rate outcomes, falsely
decreasing submission rate and falsely elevating conception rate. Consequently, this could influence clinician
decision making in interpretation of herd fertility data and prioritisation of a submission or conception rate
investigation. Furthermore, absence of recording of cow exits or barren status can falsely increase the eligible
population available for insemination and conception in fertility data analysis, artefactually decreasing
submission rates and fertility efficiency/21-day pregnancy rates.

Quantification of common types of mis-recording of herd fertility data is vital and will be presented using
herd examples with subsequent potential impact of mis-recording; understanding these factors will help
clinicians target assessment of on farm fertility records for mis-recording to common problematic areas,
ultimately maximising accuracy of fertility investigations carried out on farm.

Take home message for practitioners
Mis-recording of key fertility events can significantly impact interpretation of herd fertility data and resultant
decision making on farm. Awareness of common types of mis-recording will enable clinicians to identify these
aspects in farm records, maximising accuracy of fertility investigations carried out on farm.

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Salmonella Dublin bulk tank seroprevalence in Great Britain

Henderson, K.1, Mason, C.1, Williams, P.2,
1SRUC Vet Services, ST Mary’s Industrial Estate, Dumfries, KA19 7NY
2MSD Animal Health, Walton Manor, Walton, Milton Keynes, Bucks, MK7 7AJ

ABSTRACT
Salmonella enterica subspecies enterica serovar Dublin is the most common serovar of Salmonella enterica
diagnosed in cattle in Great Britain. It has a significant impact on the health and welfare of cattle in infected
herds, and economic costs can be significant. In addition, it is also a zoonosis which, although uncommon in
Great Britain, is more invasive than other serovars.

Previous prevalence estimates for S. Dublin in England and Wales have been obtained through environmental
cultures or single sample pan-Salmonella bulk tank serology, both of which have been shown to have relatively
low herd level sensitivities of 45% and 54% respectively (Veling and others 2002).

A knowledge of the infection status of the dairy herd is important, both at an individual herd level to
inform management decisions and monitor interventions, and at a national level to provide information on
the importance of biosecurity and the risk of introducing animals into a herd.

The current survey used the PrioCHECK® Salmonella Ab bovine Dublin ELISA. Four hundred and ten herds
from across England, Wales and Scotland were recruited according to the geographical distribution of dairy
herds i.e. if a region had 10% of the dairy herds in the country, then 41 herds were recruited. Four quarterly
milk samples were submitted from each herd and screened for antibodies to S. Dublin.

This sampling regime was based on the Danish eradication scheme, where a herd is required to have four
quarterly bulk tank results to achieve negative status, with the most recent result not more than 20 corrected
optic-density measurements (20% ODC) higher than the average of the previous four. The sensitivity of
this classification system was estimated to be 95% and the specificity at 83-98 % depending on herd level
prevalence (Warnick and others 2006).

Four hundred and one herds completed testing, and the national prevalence was 45% (95% confidence
intervals 40-50%). There were regional differences, with Wales and Scotland having the highest prevalence
and the south, east, and south-east having the lowest prevalence.

Of the 401 herds, 339 herds maintained the same status across the four sampling points, while 26 herds
fluctuated between positive and negative antibody status.

Nineteen herds had an apparent recovery, although ten of these only had a single low positive bulk tank
titre and so may have been negative herds with a false positive result. The classification system prevented
any herd with a positive result subsequently achieving a negative herd classification within the period of
the survey. However, a move from a positive result to negative result was classed as an apparent recovery,
provided the herd did not have any further positive results.

There were 244 herds which tested negative initially, and 17 of these seroconverted, giving an incidence of
7 newly infected herds per 100 herds in the course of a year. It is of note that herds that enter the study with
a negative bulk tank result cannot be classified as truly negative, as they have only one negative bulk tank
result at this point.

While the positive bulk tank result is a marker of exposure rather than confirming the presence of the
organism on farm, bulk tank antibody titres have been shown to correlate with the bacteriological farm
status, the mean yield corrected antibody measurements in individual cows and the number of cows with
high antibody titres. The level of antibodies in the bulk tank is strongly correlated with the spread of infection
within the adult herd (Wedderkopp and others 2001, Nielsen and Ersbøll 2005) and Warnick and others
(2006) estimate the positive and negative predictive values of this sampling regime at 30% prevalence to be
83 and 98% respectively, and 85% and 94% at 50% prevalence.

The estimate of true prevalence of Salmonella Dublin in the dairy herd was significantly higher than the
only previous estimate of 7.5% based on bacteriological cultures (Davison and others 2005). This concurs with
the work by Veling and others (2002) that found culture-based techniques to have a much lower herd level
sensitivity for the monitoring of infection. Nevertheless, culture-based techniques remain the diagnostic tool
of choice in the acute clinical situation, due to the length of time required for seroconversion to occur.

It is encouraging to note that, even excluding the herds which were considered to have potentially been
false positives/cross reactions, 6% of initially positive herds became seronegative within a year. While this

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is an apparent rather than a true recovery, and future titre fluctuations may occur, the Danish eradication
scheme highlights that herd level recovery is not only possible, but that the average duration of infection was
two years (Nielsen and Dohoo 2013).

Veling (2004) noted that in the Netherlands, only 50% of infected herds became endemically infected, and
whether or not this occurred was largely dependent on the hygiene and management in the initial stages
of infection. Therefore, as well as clinical vigilance, quarterly bulk tank testing can provide a relatively early
indication of infection circulating in the adult herd. This would allow control measures to be put in place
similar to those described in Nielsen and Nielsen (2012) and adapted by Henderson and Mason (2017).

The knowledge of the seroprevalence of Salmonella Dublin enables veterinary surgeons and farmers to be
aware of the risk of incursion to the herd, and of the likelihood of Salmonella Dublin being present in their
herd. The presence of Salmonella Dublin infection in a herd may go undetected because of the range of clinical
signs and production effects associated with Salmonella Dublin infection. Therefore, bulk tank serology can
be used to provide a sensitive, specific and cost-effective method of ascertaining and monitoring herd level
status.

ACKNOWLEDGEMENTS
This prevalence study was funded by MSD Animal
Health.

SRUC VS receives financial support from the
Scottish Government for farm animal disease
surveillance activities.

We would like to extend our thanks to ARLA and
to all the farmers and vets for their involvement.

REFERENCES

Davison, H.C., Smith, R.P., Pascoe, S.J.S., Sayers, A.R., Davies,
R.H., Weaver, J.P., Kidd, S.A., Dalziel, R.W., Evans, S.J. (2005)
Prevalence, incidence and geographical distribution of
serovars of Salmonella on dairy farms in England and Wales.
Veterinary Record 157: 703-711
Henderson, K., Mason, C. (2017) Diagnosis and control of
Salmonella Dublin in dairy herds. In Practice 39: 158-168
Nielsen, L.R., Dohoo, I. (2013) Time-to-event analysis of
predictors for recovery from Salmonella Dublin infection in
Danish dairy herds between 2002 and 2012. Preventative
Veterinary Medicine, 110: 370-378
Nielsen, L.R., Ersboll, A.K. (2005) Factors associated with
variation in bulk tank-milk Salmonella Dublin ELISA ODC% in
dairy herds. Prev. Vet. Med. 68: 165–179
Nielsen, L.R., Nielsen, S.S. (2012) A structured approach to
control of Salmonella Dublin in 10 Danish dairy herds based
on risk scoring and test-and-manage procedures. Food
Research International 45: 1158-1165
Veling, J., Barkema, H.W., van der Schans, J., van Zijderveld,
F., Verhoeff, J. (2002) Herd-level diagnosis for Salmonella
enterica subsp. Enterica serovar Dublin infection in bovine
dairy herds. Preventative Veterinary Medicine 53: 31-42
Veling, J. (2004) Diagnosis and control of Salmonella Dublin
infections on Dutch dairy farms. PhD thesis. Animal Health
Service, Deventer, The Netherlands, pp. 1-173.
Warnick, L.D., Nielsen, L.R., Nielsen, J., Greiner, M. (2006)
Simulation model estimates of test accuracy and predictive
values for the Danish Salmonella surveillance program in dairy
herds. Preventive Veterinary Medicine 77: 284-303
Wedderkopp, A., Stroger, U., Bitsch, V., Lind, P. (2001) Testing
of bulk tank milk for Salmonella Dublin infection in Danish
dairy herds’. Can. J. Vet. Res. 65: 15–21

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Over feeding copper during rearing and lactation increases indicators of
liver damage and decreases conception rate and milk yield in dairy cattle

McCaughern, J., Mackenzie, A.M., Sinclair, L.A., Department of Agriculture and Environment,
Harper Adams University, Edgmond, Newport, Shrops, TF10 8NB

ABSTRACT
Copper (Cu) is an essential trace element that is required as a co-factor in over 300 different proteins that
influence dairy cow fertility, health and performance (Suttle 2010). Most research has focussed on primary
Cu responsive disorders where there is insufficient Cu in the diet, or more commonly secondary responsive
disorders, where Cu absorption or metabolism is inhibited by antagonists such as sulfur, molybdenum or iron.
However, most dairy farms in the UK over-feed Cu, with 2.5 times the recommended dietary concentration
of 11mg/kg Dry Matter (DM) being fed (Sinclair and Atkins 2015). This over-feeding is reflected in 38% of
Holstein-Friesian cow livers being presented with very high or toxic levels of Cu at slaughter (Kendall and
others 2015), and in the continuing number of cases of Cu toxicity reported in both dairy calves and adult
cows. Reasons for over-feeding Cu are unclear, although there is a belief by some that in the absence of Cu
toxicity there is no detrimental effect from over-feeding (Jacklin 2016). The aim of this controlled study was
to determine the long-term effects of Cu feeding level on the health, fertility, performance and indicators of
liver damage in dairy heifers when reared from 4 months of age until 14 weeks of lactation.

Eighty Holstein-Friesian calves from the Harper Adams University dairy herd that were 4.1 months of age
(SE ± 0.1) and weighing 137kg (SE ± 2.4) were paired based on their live weight, condition score, and predicted
transmitting ability for milk component yield, and randomly allocated to one of two dietary Cu concentrations.
The control (C) basal diet contained 15mg Cu/kg DM, and was predicted to meet the animal’s requirements
(NRC 2001). Heifers on the high (H) concentration received an additional 15mg Cu/kg DM supplied using
intra-ruminal Cu oxide boluses to provide a total dietary concentration of approximately 30mg Cu/kg DM,
which was similar to the mean concentration reported on UK dairy farms by Sinclair and Atkins (2015). Heifers
were weighed and condition scored on a fortnightly basis, and were served by artificial insemination from
13.5 months of age. Liver biopsy samples were collected at 7, 13 and 22 months of age and after 14 weeks of
lactation. Blood sample were collected monthly and analysed for plasma Cu and glutamate dehydrogenase
(GLDH) as an indicator of liver damage.

Over the rearing period heifers on treatment H had a 0.04kg/d higher growth rate (P<0.05) and a 0.17
higher gain in body condition score (P<0.05) compared to those on C. The combined conception rate to 1st
and 2nd service was substantially lower for heifers on H compared to C (P<0.01). Heifers on treatment H had
hepatic Cu concentrations that were 155, 155, 165 and 183mg/kg DM higher (P<0.01) than those on C at 7,
13 and 22 months of age, and 14 weeks of lactation respectively. Plasma Glutamate dehydrogenase (GLDH)
concentrations were very high at the start of the study in heifers on either treatment at approximately 125
U/L compared to the maximum reference threshold of 25 U/L. Plasma GLDH concentrations were higher
(P<0.05) in heifers receiving H than C during the rearing period, and were almost 3x as high as C in early
lactation (P<0.05). Milk yield in the first 2 weeks post-calving was lower (P<0.05) in cows fed H than C. It is
concluded that, in the absence of clinical toxicity, over-feeding Cu results in indicators of liver damage, reduces
conception rate and decreases milk performance in early lactation. It is recommended that the dietary supply
of Cu from all sources is accounted for when rationing (including forages), and that the recommended dietary
concentration is not exceeded unless there are high background concentrations of antagonists such as sulfur
and molybdenum.

REFERENCES dairy cattle. 7th revised edition. National Academy Press,
Washington D.C.
Jacklin, D. (2016) Cattle Nutrition: Excess dietary copper. Vet. Sinclair, L.A., Atkins, N.E. (2015) Intake of selected minerals
Rec. 178: 123 on commercial dairy herds in central and northern England in
Kendall, N.R., Holmes-Pavord, H.R., Bone, P.A., Ander, E.L., comparison with requirements. J. Agric. Sci. 153: 743-752
Young, S.D. (2015) Liver copper concentrations in cull cattle Suttle, N.F. (2010) Mineral nutrition of livestock 4th edition,
in the UK: Are cattle being copper loaded? Vet. Rec. 177: CABI Publishing, Wallingford, UK
493-496

National Research Council (2001) Nutrient requirements of

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Effects of farmer-assisted parturition and postpartum NSAID treatment
on future productivity of dairy calves

Gladden, N., Room 227 McCall Building, University of Glasgow School of Veterinary Medicine, 464
Bearsden Road, Glasgow, G61 1QH

BACKGROUND interestingly, birth assistance had a negative impact
Parturition assistance is common — affecting on first lactation reproductive performance with
up to 50% of calf births — but few studies have assisted calves having a longer first lactation calving
investigated the impact on future calf production. to conception interval (p=0.027) and needing more
Birth-related pain experienced by calves is rarely insemination attempts (p=0.001) than unassisted
studied and it is unclear if analgesia has a beneficial calves. Similarly, although birth experience did not
effect on subsequent calf production. This study affect the risk of being culled before first calving,
aimed to investigate the effects of farmer-assisted birth assistance was associated with an increased
birth and immediate post-birth NSAID analgesia on likelihood of failing to complete the first lactation
the productivity of dairy calves from birth until the (OR = 7.95; 95% CI 1.31 to 48.4; p=0.024).
end of their first lactation.
CONCLUSIONS
METHODS The results of this study demonstrate the far
91 Holstein dairy calves (47 assisted, 44 unassisted) reaching negative effects of assisted birth on
were randomly assigned to receive a single dose calves and highlight the importance of ensuring
of either NSAID analgesia (ketoprofen) or saline birth assistance is judiciously applied. Ketoprofen
placebo within 3h of birth in a 2x2 design. Data administration was associated with improved
relating to growth rate, health status, survival growth rates of assisted calves (before weaning)
and reproductive performance before first calving which had a subsequent effect on reproductive
and data relating to milk production, reproductive performance. These findings suggest that
performance, and survival in the first lactation administration of ketoprofen to dairy calves at
were obtained from farm records. Multivariate birth may have some beneficial production effects,
regression analyses were performed to investigate but these did not extend beyond weaning.
the effects of birth assistance, NSAID treatment
and assistance x treatment interactions on
measures of production of calves from birth up to
and including first lactation.

RESULTS
Growth rate to weaning of ketoprofen-treated
assisted calves was approximately 0.1kg/d higher
than calves in the other three interaction groups
(placebo-treated assisted and ketoprofen-treated
unassisted) (p=0.041). Reproductive performance
was not directly affected by ketoprofen treatment
but growth rate to weaning was negatively related
to age at first observed oestrus with each 0.1kg/d
weight gain before weaning being associated with
a 10d decrease in age at first observed oestrus (p=
0.004). Bovine respiratory disease (BRD) was also
identified to have a negative impact on reproductive
performance before first calving: calves previously
diagnosed with BRD had four times the odds of
oestrus not being detected than healthy calves (OR
3.76; 95% CI 1.04, 13.6; p=0.043).

Reproductive performance before first
calving was not affected by birth assistance but,

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CATTLE PRACTICE VOLUME 29 PART 1

A prospective cohort study on the periparturient muscle tissue mobilisation in
high producing dairy cows

Hatfield, C.1, Tulley, W.1, Hall, R.1, Griffiths, B.E.1, Foskolos, A.2, Smith, R.F.1, Oikonomou, G.1,
1Department of Livestock and One Health, Institute of Infection, Veterinary and Ecological Sciences,

University of Liverpool, University of Liverpool, Leahurst Campus, Neston, Wirral, CH64 7TE
2Department of Animal Science, University of Thessaly, Greece

OBJECTIVES tercile had higher MT measurements comparing to
Dairy cattle at the onset of lactation experience a the other two terciles but there were no significant
period of Negative Energy Balance (NEB). Adipose Milk PTA tercile by time interaction. A lower pre-
tissue is mobilised to meet energy demands for milk calving BCS was associated with increased MT
production, through the use of non-esterified fatty loss. Higher MT Pre-Calving (PC) was associated
acids (NEFAs). There is evidence that some cows with increased MT loss (For every 1mm of muscle
will also begin to mobilise muscle during the dry thickness PC, estimated loss -0.45mm ± 0.039,
period prior to fat mobilisation. The objectives of P<0.0001). Significant fat mobilisation occurred in
our study were to i) investigate the changes in the the period between the fresh and the early lactation
thickness of the Longissimus dorsi muscle in high measurements. Cows in the lowest Milk PTA tercile
producing dairy cows during the periparturient had higher BFT measurements comparing to the
period, ii) identify factors associated with these other two terciles but there was no significant Milk
changes and iii) describe their possible associations PTA tercile by time interaction. Farm 3 had greater
with cattle reproductive performance. odds of having higher NEFAs at fresh comparing to
farm 1 and 2 (OR: 39.73 CI=15.45-102.14, and OR:
MATERIALS AND METHODS 9.68, CI 4.04-23.21 respectively). Later parity cows
We enrolled 455 cows from three farms with data had greater odds of high NEFA concentrations than
collected for 500 lactations (312 from Farm 1, 75 1st and 2nd parity cows (OR: 2.48, CI=1.00-6.19
from Farm 2, and 113 from Farm 3). Data were and OR: 2.50, CI=1.07-5.83 respectively). Cows with
collected from each animal on three occasions a BCS PC of >3 were at higher odds of increased
per lactation: 3-4 weeks before the expected NEFAs at fresh (FR) compared to those with a BCS
date of parturition (pre-calving), 0-10 day’s post- of 2.5-3 (OR: 5.69 CI=2.42-13.37). MT loss PC to FR
partum (fresh) and approximately 60-80 days was not associated with increased NEFAs indicating
post-partum (early lactation). At each time point MT measurements represented muscle mass
blood samples were collected from the coccygeal changes and not mobilisation of intra-muscle fat.
vein for measurement of NEFAs; Body Condition Cows in the MT pre-calving to early lactation 3rd
Score (BCS), Muscle Thickness (MT), and Back Fat tercile (cows that had minimal loss of MT or gained
Thickness (BFT) were also recorded. Muscle and MT during the studied period) were served earlier
fat thickness were measured using an Easi-Scan than cows in the 1st tercile (cows with the greater
ultrasound machine. Longissimus dorsi depth was loss of MT) (Hazard risk ratio: 1.28, CI=0.96-1.69,
measured perpendicular to the skin at the fourth P=0.09). Additionally, cows in the top fertility index
lumbar process. Farm fertility records were used tercile (better genetics for fertility) were served
and genomically estimated breeding values were earlier than cows in the lowest fertility index tercile
also available. Associations between variables were (Hazard risk ratio: 1.42, CI=1.07-1.88, P=0.015) and
analysed with the use of multivariable linear and had a lower calving to conception interval (Hazard
logistic regression models; cox proportional hazard risk ratio: 1.73, CI= 1.11-2.68, P=0.015).
analysis was used for fertility outcomes.
CONCLUSIONS
RESULTS Our study advances our understanding of
Explanatory variables using MT as an outcome periparturient muscle tissue mobilisation in dairy
found assessor had a significant effect on MT (P< cattle and highlights its potential associations
0.0001). Muscle thickness decreased in the period with cattle fertility. We have identified significant
between the pre-calving and fresh measurement mobilisation of body fat and muscle tissue across
with apparent between farm differences. Cows in the transition period in dairy cows. Asynchrony in
the lowest milk predicted transmitting ability (PTA) mobilisation of fat and muscle suggests that NEB is

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not the sole underlying cause of muscle catabolism,
and that a variety of different uses are possible for
the mobilised amino acids. Variation in genetics,
diet and environment at individual and herd level
provide potential mechanisms to manipulate the
amount of muscle catabolised in the peri-partum
period and as such further study is warranted in
these areas.

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Diagnostic sampling: What type of samples do I take and how do I get the
best chance of a result?

Murphy, A., Swinson, V., APHA, West House, Station Road, Thirsk, North Yorkshire, YO7 1PZ

ABSTRACT
This workshop will discuss the collection of diagnostic samples, focussing on those taken at postmortem
examination (PME). Guidance on getting the most from the samples collected will be provided, as well
determining when submission of the carcase, or viscera, to a dedicated PME provider might be preferable.

We will start with a brief discussion of the postmortem provider network, and where to go for advice about
on-farm PMEs. This will include instruction on what to do if a notifiable disease is suspected.

The overall approach to a PME will be described, with focus on specific syndromes/systems including:
• Systemic disease - such as when non-infectious disease is suspected
• Enteric – such as investigations of potential anthelmintic resistance
• Respiratory – improving bacteriology samples, histology samples etc
• Sampling for joint, skeletal and neurological cases
• Abortion and stillbirth investigations

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CHeCS Health Schemes: IBR, Lepto, Neospora – where do we start?

Carty, H., SRUC Veterinary Services, J F Niven Building, Auchincruive Estate, Auchincruive, Ayr, KA6
5HW

ABSTRACT
The CHeCS Health Schemes are widely recognised as a great tool to identify and eradicate / control the major
infectious diseases of cattle. Other initiatives have raised the profile of BVD eradication and Johne’s control
resulting in many herds being “signed up” for these two diseases. There is a vast amount of high quality online
CPD on these topics… but what about the other diseases?

Is it worth including IBR, Lepto or Neospora in your client’s next annual herd test?
This workshop will cover these three diseases and what is needed to make progress with accreditation. It
will also identify the common stumbling blocks with these diseases and give tips on how to address them.
All in 60 minutes!!!

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A prospective cohort study into the association between early-lactation
mastitis and the development of sole ulcers in dairy cows

Watson, C.1, Barden, M.2, Griffiths, B.2, Anagnostopoulos, A.1, Higgins H.1, Bedford, C.1, Psifidi, A.3,
Banos, G.4, Oikonomou, G.1,2,
1Department of Livestock Health and Welfare, Institute of Veterinary Science, University of
Liverpool, Leahurst Campus, Chester High Road, CH64 7TE
2Department of Epidemiology and Population Health, Institute of Infection and Global Health,
University of Liverpool. Leahurst Campus, Chester High Road, CH64 7TE
3Department of Clinical Science and Services, Royal Veterinary College, North Mymms,
Hertfordshire, AL9 7TA
4Animal and Veterinary Sciences, SRUC, Roslin Institute Building, Easter Bush, Midlothian, EH25
9RG

KEYWORDS: Sole ulcer, lameness, mastitis

OBJECTIVES RESULTS
Sole ulcers (SU) are a major cause of lameness in Of the cows that had mastitis in the first 30 days
dairy cattle and their incidence is highest in early to post calving 16.3% developed SU in early lactation,
mid-lactation (Sanders and others 2009). SU take whilst only 5.9% of cows that did not have mastitis
8-12 weeks or more to develop, and it has been in the first 30 Days in Milk (DIM) developed SU in
suggested many originate from insults occurring in early lactation. After correcting for farm, parity, BCS
the periparturient period (Shearer and others 2017). at early lactation check, timepoint of early lactation
The risk for clinical mastitis is highest in the first 30 check and presence of SU at pre-calving check or
days in milk (DIM) (Breen and others 2009) and we calving check, the odds of developing SU in early
postulate a potential link between early-lactation lactation were 2.44 times greater in cows that had
mastitis incidence and later development of SU. A mastitis in the first 30 DIM compared to cows that
preliminary study that was carried out by our group did not have mastitis in the first 30 days’ post calving
involving 455 animals on 3 commercial dairy farms (CI 0.97-5.54, p=0.042). The odds of developing SU
found that cows were significantly more likely to in early lactation was 7.56 times greater if cows had
develop SU in early lactation if they had mastitis SU pre-calving or when freshly calved compared
in the first month post calving (Griffiths and others to cows that did not have SU pre-calving or when
2018). The aim of this prospective cohort study was freshly calved (CI 4.46-12.76, p<0.001).
to further investigate this association employing a
much larger dataset and more intensive recording Cows had lower odds of developing SU in early
of lameness-causing foot lesions. lactation if they were in their 2nd parity (OR x0.13,
CI 0.06-0.25, p<0.001) compared to primiparous
MATERIALS AND METHODS cows or those in second or greater lactation.
Data were collected from 2,353 Holstein-Friesian
cows and heifers raised in four commercial dairy They also had lower odds of developing SU in
farms in the UK. Data were collected from each early lactation if they had BCS 2.50-3.0 (OR x0.45,
animal on three occasions: - at drying off or 30- CI 0.27-0.75, p=0.002) or greater than 3.0 (x0.32,
60 days before their expected first calving, in CI 0.19-0.57, p<0.001) compared to cows with BCS
the first 14 days post calving and at 50-120 days less than 2.5 at early lactation check.
post calving. On each occasion, feet were lifted
and presence and severity of sole haemorrhage When cows that had SU at drying off or at the
and SU was recorded by a veterinary surgeon. calving check were excluded from the dataset, an
Mastitis episodes were recorded by trained association of mastitis in the first 30 DIM with later
farm staff. A series of univariable analyses were development of SU was still seen but was no longer
initially performed. Outcome of interest was the significant (OR 2.25, CI 0.81-5.34, p=0.09).
presence of a SU in early lactation. To account for
potential confounding factors, multivariable logistic CONCLUSION
regression models were also fitted to the data. Our results are consistent with those described
previously by Griffiths and others (2018). A strong
association has been found between mastitis in
the first 30 days and the presence of SU in peak

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lactation. The mechanism responsible for this
association is not yet clear and warrants further
investigation. Elucidating this mechanism may lead
to new preventive strategies for SU.

REFERENCES

Breen, J.E., Green, M.J., Bradley, A.J. (2009) Quarter and cow
risk factors associated with the occurrence of clinical mastitis
in dairy cows in the United Kingdom. Journal of Dairy Science
92(6): 2551-61
Griffiths, B., Mahen, P., Hall, R., Kakatsidis, N., Britten, N.,
Robinson, L., Tatham, H., Jenkin, R., Oikonomou, G. (2018)
Periparturient changes in the thickness of the digital cushion
in dairy cows; associations with claw horn disruption lesions.
Cattle Practice 26: 81
Sanders, A.H., Shearer, J.K., De Vries, A. (2009) Seasonal
incidence of lameness and risk factors associated with thin
soles, white line disease, ulcers, and sole punctures in dairy
cattle. Journal of Dairy Science 92(7): 3165-74
Shearer, J.K., van Amstel, S.R. (2017) Pathogenesis and
Treatment of Sole Ulcers and White Line Disease. Veterinary
Clinics: Food Animal Practice 33(2): 283-300

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Investigating the use of thermal imaging as a diagnostic tool for the
detection of different stages of Digital Dermatitis in dairy cattle

Anagnostopoulos, A.1, Williams, K.1, Barden, M.1, Griffiths, B.1, Bedford, C.1, Rudd, M.1, Psifidi,
A.2, Banos, G.3, Oikonomou, G.1,
1University of Liverpool, Leahurst Campus, Neston, CH64 7TE
2Royal Veterinary College, Hawkshead Ln, Brookmans Park, Hatfield, AL9 7TA
3Scotland's Rural College, The Roslin Institute Building, Easter Bush Campus, Midlothian, EH25 9RG

OBJECTIVES highest in feet with M2 lesions, followed by M1
Bovine Digital Dermatitis (BDD) is one of the major and M4.1 lesions. Model predicted means (±SE)
causes of lameness in dairy cattle with increasing for IST and for different DD stages were: 26.60 °C
economic and welfare importance (Evans and ± 0.15, 28.30°C ± 0.34, 31.70°C± 0.28, 27.40°C±
others 2016). Our aim was to investigate whether 0.28, 27°C± 0.18, and 29.30°C± 0.38 for M0, M1,
interdigital skin temperature (IST), measured using M2, M3, M4, and M4.1 stages respectively. The
infrared thermography (IRT), is affected by the average area under the curve for the mixed effect
different stages of digital dermatitis (DD) lesions. logistic regression model was 0.80 when its ability
Additionally, we developed and validated models to detect presence of active DD was tested on 10%
that can use IST measurements to identify cows of the data that were not used for the model’s
with an active DD lesion. training; an average sensitivity of 0.77 and an
average specificity of 0.67 was achieved. The
MATERIALS AND METHODS validation of the simplified version of this model
This study was conducted on four dairy farms in the demonstrated an average area under the curve of
UK. A total of 12,221 IRT images from 2,334 dairy 0.78, a sensitivity of 0.88, and a specificity of 0.66
cows were collected between March 2019 and for 1 of the time points (precalving).
March 2020. All images were taken from the plantar
aspect of both hind feet from an approximate CONCLUSION
distance of 30cm. A Flir E8 Wi-Fi Thermal Camera The study showed that IRT imaging could be
was used. Ambient temperature (AT) at the time of effective in detecting all active DD lesions. M2
the image capturing was also recorded. Pregnant stage lesions resulted in the highest IST which was
animals were enrolled approximately 1 to 2 months significantly higher than that of any other stage.
pre-calving, reassessed 1 week after calving, and Our study adds further evidence to the impact of
again at approximately 50 to 100 days postpartum. DD lesions on the foot skin temperature using a
Using the Flir software the maximum temperature large dataset and a population of cows examined
of the interdigital skin (IST) between the heel bulbs multiple times over the duration of this one-year
was measured. DD lesions were assessed using the study. Additionally, the capability of our models
M-stage scoring system (Solano and others 2017). A suggest that a more sophisticated DD detection
mixed effect linear regression model with IST as the system, using thermographic imaging, could be
dependent variable was fitted. The capacity of IST feasible on a farm setting in the near future.
measurements to detect the presence of an active
DD lesion (M1, M2, or M4.1) was explored by fitting REFERENCES
logistic regression models, which were tested using
10-fold validation. A mixed effect logistic regression Evans, N.J., Murray, R.D., Carter, S.D. (2016) Bovine digital
model with the presence of active DD as the dermatitis: Current concepts from laboratory to farm. Vet J.
dependent variable was fitted first. This model was 211: 3-13. doi:10.1016/j.tvjl.2015.10.028
then simplified so that only variables that could Solano, L., Barkema, H.W., Jacobs, C., Orsel, K. (2017)
easily be collected on a commercial farm setting Validation of the M-stage scoring system for digital dermatitis
were included as explanatory. on dairy cows in the milking parlor. J. Dairy Sci. 100(2): 1592-
1603. doi:10.3168/jds.2016-11365

RESULTS
Interdigital skin temperature was associated with

DD lesions. Compared to healthy feet, IST was

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Can we breed claw horn lesions out of dairy cows?

Barden, M.1, Li, B.2, Anagnostopoulos, A.1, Griffiths, B.1, Bedford, C.1, Psifidi, A.3, Banos, G.2,
Oikonomou, G.1,
1Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus,
Liverpool, CH64 7TE
2Scotland’s Rural College, The Roslin Institute Building, Easter Bush, Edinburgh, EH25 9RG
3Department of Clinical Science and Services, Royal Veterinary College, North Mymms,
Hertfordshire, AL9 7TA

BACKGROUND lesion – cows were considered affected if any foot
Lameness is one of the most serious welfare at any stage in lactation had the lesion present,
problems facing the modern dairy industry (Nalon compared to cows in which the lesion was absent
and Stevenson 2019). Claw horn lesions, such on all feet at all stages.
as sole haemorrhage, sole ulcers, and white line
lesions have the highest prevalence in dairy cattle Sole haemorrhage and sole ulcers were
(Somers and O’Grady 2015, Arango-Sabogal and additionally considered as a single lesion. A
others 2020). The prevalence of lameness in the categorical trait (0-4) was defined using four grades
national herd has not reduced over the past 30 of sole haemorrhage severity (0-3) plus sole ulcers
years despite an increased emphasis on as an additional level representing the extreme
environmental management (Afonso and others form of this combined lesion. Finally, changes in
2020). Breeding strategies for functional traits sole haemorrhage/ulcer severity between early
such as fertility and udder health have shown and late lactation were analysed by classifying
good success in recent years, but genetic gain in animals as having either chronic or recovered
foot health has lagged behind. One of the main lesions. A binary trait was defined to differentiate
barriers to breeding for lameness resistance is the these two groups. Analysis was conducted using
absence of reliable phenotypic data to accurately the BLUPF90 suite of software. In all cases, genetic
characterise the genetic background to specific parameters were estimated with threshold models
foot lesions. using Gibbs sampling. Both genetic and pedigree
relationships were incorporated into the analysis
The objective of this study was to determine following a single-step approach; a fixed parity
the genetic parameters of sole haemorrhage, sole effect and a random herd-year-season effect were
ulcers, and white line lesions in Holstein dairy cattle also included in each model to adjust for systematic
using phenotypic data from detailed foot lesion environmental variation.
records that were collected specifically for this
purpose. RESULTS
Across the whole study period, 77.3% of cows had
MATERIALS AND METHODS sole haemorrhage (any severity grade) at least
Over an eight-month period, 2,352 Holstein cows once, likewise 11.6% and 82.2% recorded sole
were enrolled on four dairy farms and subsequently ulcers and white line lesions respectively.
assessed at four stages of a lactation cycle: pre-
calving (average: 56 days before calving); freshly Combining data from all stages indicated that
calved (average: 5 days after calving), early lactation the heritability of sole haemorrhage, sole ulcer,
(average: 84 days after calving) and late lactation and white line lesion resistance was 0.20, 0.29 and
(average: 182 days after calving). At each stage, 0.06, respectively. The genetic correlation between
feet were inspected by a veterinary surgeon and all stages of lactation within each lesion was high for
foot lesions were recorded and scored according to both sole haemorrhage and sole ulcers but variable
severity (Egger-Danner and others 2015). for white line lesions. The genetic correlation
between sole haemorrhage and sole ulcers was
Pedigree information was available for all cows; 0.92, between sole ulcer and white line lesions
50K SNP genotypes were obtained for 2,250 cows 0.73, and between sole haemorrhage and white
and imputed to 80K genotypes. Different traits line lesions 0.29.
were then defined based on the lesion severity
recorded at each stage of lactation. A binary trait The heritability for sole haemorrhage and sole
was defined to describe overall resistance to each ulcers combined was 0.20. In early lactation, 528
cows had either moderate/severe sole haemorrhage

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or a sole ulcer; 41.6% of these cows had recovered REFERENCES
by the following assessment in late lactation. The
heritability for the trait which differentiated cows Afonso, J.S., Bruce, M., Keating, P., Raboisson, D., Clough,
which recovered from these lesions and cows H., Oikonomou, G., Rushton, J. (2020) Profiling Detection
which remained chronically affected was 0.32. and Classification of Lameness Methods in British Dairy Cattle
Research: A Systematic Review and Meta-Analysis. Frontiers
CONCLUSIONS in Veterinary Science 7: 542 doi: 10.3389/fvets.2020.00542.
Almost all previous reports of foot lesion heritability Arango-Sabogal, J.C., Desrochers, A., Lacroix, R., Christen,
are based on foot-trimmer or farm records. The A-M., Dufour, S. (2020) Prevalence of foot lesions in Québec
heritability estimates of sole haemorrhage and sole dairy herds from 2015 to 2018. Journal of dairy science
ulcers in this study suggest a higher heritability to 103(12): 11659–11675. doi: 10.3168/jds.2020-18191.
these lesions than the majority of previous studies, Egger-Danner, C., Nielsen, P., Fiedler, A., Müller, K., Fjeldaas,
this is particularly true for sole haemorrhage. This T., Döpfer, D., Daniel, V., Bergsten, C., Cramer, G., Christen,
highlights the need for foot-trimming and farm A.-M., Stock, K.F., Thomas, G., Holzhauer, M., Steiner, A.,
records to include mild or non-painful lesions if Clarke, J., Capion, N., Charfeddine, N., Pryce, J.E., Oakes, E.,
these are used as the primary source of phenotypic Burgstaller, J., Heringstad, B., Ødegård, C., Kofler, J. (2015)
data for genetic evaluations. ICAR Atlas of Claw Health. 9295014146. Rome, Italy. Available
at: http://www.icar.org/Documents/ICAR_Claw_Health_Atlas.
The genetic correlation between stages of pdf.
lactation was high for sole haemorrhage and sole Nalon, E., Stevenson, P. (2019) Addressing lameness in
ulcers indicating that the genetic basis for these farmed animals: An urgent need to achieve compliance with
lesions was not dependent on environmental EU animal welfare law. Animals 9(8): 3–7. doi: 10.3390/
factors which were specific to the stage of lactation. ani9080576.
In contrast, both the heritability and between- Somers, J., O’Grady, L. (2015) Foot lesions in lame cows on 10
stage genetic correlation were low for white line dairy farms in Ireland. Irish Veterinary Journal 68(1): 10. doi:
lesions. Taken together these results suggest that 10.1186/s13620-015-0039-0.
white line lesions only have a small underlying
genetic component, and this varies depending on
environmental factors.

The genetic correlation between sole
haemorrhage and sole ulcers was high, this lends
support to the frequent assertion that both lesions
share a similar pathogenesis. The heritability
estimate for sole haemorrhage and sole ulcer
recovery suggests that a cow’s response to these
lesions also has a genetic basis.

Overall these results indicate there is scope to
improve resistance to, and the ability to recover
from, sole haemorrhage and sole ulcers. Progress in
breeding for these traits is reliant on the availability
of consistent and accurate foot lesion records.

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Setting our heifers up to succeed; the use of NSAIDS in the prevention and
treatment of lameness

Wilson, J.P.1, Green, M.J.2, Randall, L.V.2, Rutland, C.S.2, Bell, N.J.2, Hemingway-Arnold, H.2,
Thompson, J.S.2, Bollard, N.J.2, Huxley, J.N.3,
1Duchy College, Stoke Climsland, Callington, PL17 8PB
2University of Nottingham, School of Veterinary Medicine and Science, Sutton Bonington Campus,
Leicestershire, LE12 5RD
3Massey University, School of Veterinary Science, Private Bag 11 222, Palmerston North 4474, New
Zealand

ABSTRACT
Claw horn lesions (CHLs – sole haemorrhage, sole ulceration, and white line disease) are a prevalent and
recurrent cause of lameness in dairy systems globally. These are conditions that compromise the health
and welfare of dairy cattle and can challenge the economic viability of a dairy enterprise. Despite our
understanding of the importance of these lesions, our knowledge surrounding their pathogenesis remains
poor. It has previously been identified that lameness begets lameness and that CHLs are correlated with
pathological change to the anatomy of the bovine distal limb. The treatment and prevention of lameness
derived from CHLs may play a vital role in protecting the functional anatomy of the hoof. If this anatomy can
be protected, then it is believed that the animal is less likely to experience CHLs in the future. From previous
research, the inflammatory aetiology of the CHLs is hypothesised to be a driving force behind the pathological
change that occurs. Further to this, there is a growing body of evidence to suggest that inflammation
experienced by the dairy cow around the transition period (and the degree to which it exists) can be highly
influential on the future health status of the animal. The impacts of transition period inflammation on lameness
have never been examined before. Indeed, non-steroidal anti-inflammatory drugs (NSAIDs) have been shown
to be important in improving cure rates when used as part of a treatment regimen for CHLs. This has been
demonstrated through single outcome measures, however their efficacy in the long-term management of
lameness within the dairy herd has never been examined.

This study examined the efficacy of NSAID administration in the treatment and prevention of lameness
through the implementation of a thirty four month-long long randomised controlled trial (RCT). Holstein
cattle within the study herd were subjected one of four treatment groups for the entirety of the study period
with lameness scoring and treatment administered on a fortnightly basis and a blinded outcome score
occurring fortnightly. Two cohorts of animals were identified during data analysis – those heifers that calved
into the trial after initiation, and animals already milking when the trial began.

The heifers calving into the study were subjected to treatment regimens from first calving through until the
end of the study period or culling. From this study, it was identified that animals that received NSAID at first
and subsequent calvings, and at lameness events were at a significantly reduced risk of being scored as lame
or culled when compared to those that received no NSAID at calving or lameness. It was hypothesised that
systemic inflammation at calving can initiate pathological change to distal limb anatomy which predisposes
an animal to CHL onset. Furthermore, the effect size and robust nature of the RCT gives strength to the case
for routine administration of NSAID at calving for the purposes of lameness management. The effect size
observed presents a substantial opportunity to reduce the prevalence of lameness in the global dairy herd
substantially.

The adult cow dataset identified no effect of NSAID administration at calving or lameness on the risk of an
animal being scored as lame or culled from the herd. It could be suggested that these animals have already
had some degree of pathological change to distal limb anatomy associated with either transition or lameness
which has led to a predisposition to future lameness which cannot be undone. This predisposition may
counteract any benefits associated with NSAID administration as a treatment or prevention, meaning that
with regards to long term lameness management, there is little if any positive prospect for animals that have
been previously lame or calved without NSAID administration. The authors, however, do not diminish the
importance of the pain management associated with NSAID administration.

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Minimising antibiotic use through husbandry approaches

Bailey, E., George Farm Vets, 18-20 High St, Malmesbury, SN16 9AU and The Soil Association, Soil
Association, Spear House, 51 Victoria Street, Bristol, BS1 6AD

ABSTRACT
Livestock farming has made huge progress in reducing antibiotic use by nearly half since 2014. However,
progress has slowed with most of the low-hanging fruit already picked. A benchmarking project undertaken
for the Alliance to Save Our Antibiotics and the Soil Association showed potential routes for significant further
progress in reduction of antibiotic use. Vets need to be at the forefront of this, working collaboratively with
farmers to share knowledge and best practice. Excellent communication and facilitation skills need to be
combined with a deep knowledge of husbandry and farmers’ aims and motivations.

The data presented in the 2021 report by the Alliance to Save Our Antibiotics and the Soil Association shows
that much lower levels of use are being achieved in organic farming than the national average figures. This
suggests that focusing only on antibiotics policies and regulations, with insufficient attention being given
to husbandry factors contributing to disease, will not deliver the very low levels of antibiotic use that are
needed. Several key husbandry factors were identified by farmers as being important to very low levels of
antibiotic use, but vets were universally identified as the most trusted source of information for medicines
and treatment.

This knowledge, combined with communication techniques such as Motivational Interviewing and Farmer-
Led Action Group facilitation, will be key to the success of the Farm Vet Champions project being co-ordinated
by RCVS Knowledge.

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Demystifying camelids for cattle vets

Sawran, A., Westpoint Farm Vets (Chelmsford), Unit 5, Whitbreads Business Centre, Whitbreads,
Farm Lane, Chatham Green, Chelmsford, Essex, CM3 3FE

BACKGROUND their herd, which could be welcome news to
The service that camelids are afforded has been vets already offering such services to different
historically dependent on a herd’s location – with species. With insight from experienced production
luck they may have been under the care of a animal veterinarians, there is potential to reduce
camelid-specific service, however the vast majority communicable disease transmission among other
have fallen into a grey area between production farmed species. It is therefore in all our interest
animal and equine veterinary care. This has meant that camelid owners are informed on matters
distinct variation in the service afforded to camelid of disease risk reduction and biosecurity – to do
clients, and a potential missed opportunity to this, we must, as production vets, make efforts to
streamline our approach to infectious disease that extend clinical services in the hope of having these
affects many farm species. important discussions.

THE CASE FOR CATTLE PRACTITIONERS SESSION OUTLINE
As pseudo ruminant producers of high-end fibre, This session aims to arm cattle practitioners with
and able to contract rather more farm-specific the skills required to undertake clinical examination
diseases such as TB, Johne’s and BVD, it can be and determine differential diagnoses for common
argued that camelids fit more into the remit of a camelid presentations. Emphasis will be put on
farm practice, however it is acknowledged that the handling and restraint, and clinical examination
equine veterinary hospital may be more equipped parameters compared to those of cattle and sheep.
in intensive care of the neonate. Individual animal It will identify differential diagnoses for common
medicine notwithstanding, population medicine is and emergency presentations (with indicators of
something honed and practiced each day by cattle urgency) as well as identification of treatment
vets, and it is a skill that the UK camelid herd can pathways that are directly comparable to the more
benefit from. familiar species. Avenues for diagnostics will be
discussed (as certain laboratory tests for common
A lack of understanding of their rather particular diseases can differ), and a camelid calendar will
physiology and clinical quirks has likely fostered outline key times of year for routine practices as
camelids’ ‘in between’ state and coupled with well as disease risk periods.
(until recently) little undergraduate teaching on
the subject, camelid calls can often be viewed as a OUTCOMES
nuisance to the traditional cattle practitioner. It is hoped that those underconfident in the
handling, examination, diagnostics, treatment and
However, numbers are rising, and so too is prognostic indicators in camelids will feel equipped
demand for proactive clinical service. The British to deal with incoming calls after this session, and, by
Alpaca Society Reports 35,000 adult registrations, building relationships with camelid clients, further
accounting for approximately half of the UK adult strengthen a combined effort to reduce infectious
population. With an additional estimated 4000+ disease incidence across all ruminant and pseudo-
llamas in the UK according to the British Llama ruminant farmed species.
Society, the camelid population is fast becoming
one that we, as farm practitioners, cannot ignore.

BRIDGING KNOWLEDGE GAPS
It is acknowledged that practices may be reluctant
to take on a novel species, particularly one that
can suffer from accelerated disease processes,
carrying emotional and commercial value as both
companions and commercial stock. In the author’s
experience of working with camelids, it is evident
that most owners wish to pursue diagnostics and
embark upon schemes and practices that benefit

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Field anaesthesia in cattle

Hallowell, G., Professor of Veterinary Internal Medicine and Critical Care, University of
Nottingham, Sutton Bonington, Loughborough, LE12 5RD

DECISION-MAKING appropriate place to perform the procedure
In many cases in bovine practice, procedures are considering induction, but most importantly
performed under local blockade with procaine recovery that can be safe for you and the animal-
with the provision of a systemic NSAID, usually the latter may require the animal to be moved
without sedation. These procedures include those with the aid of people, tarpaulin, tractors etc. It is
that would normally be performed under general always helpful to have a plan A and plan B. I think
anaesthesia in other species. The reasons for this that this is one of the most challenging things for
include limited licensed pharmacological agents field anaesthesia in cattle. The surface needs to
with MRL’s, unpredictable response to sedatives be cushioned for larger animals to help prevent
and long-standing development of very effective muscle damage, but the area contained so that the
techniques utilising a standing approach. However, animal has sturdy walls to lean against if it recovers
there are times when recumbency is required for sub-optimally.
safe completion of a procedure, either for the
animal or the veterinary surgeon. The next important step is induction. Have a clear
plan of how you plan to administer the drugs and
Unlike in other species, there is usually a process where. I will discuss agents available below, but
to decide that general anaesthesia is required and a key to success is administering the drugs to a
warranted. It may be safer than utilising heavy relatively unstressed animal and ensuring you are
sedation with xylazine or detomidine and will likely not administering them intra-fat – you are doomed
have less impact on the cardiovascular system to failure if either of these elements are not met.
of the animal. Ideally the decision to undertake
general anaesthesia should not be made after The other key difference from other species is
multiple attempts to complete the procedure saliva. Ruminating animals produce a huge quantity
utilising standard techniques and sedation, unless of saliva that turns floors into skating rinks. Some
the procedure is an emergency. way to mop up this saliva (and protect the cow’s
eyes) is really important for everyone’s safety.
Thus, it will usually be for the very difficult
patient, particular or unusual procedures that PHARMACOLOGICAL AGENTS FOR INDUCTION
general anaesthesia will be selected over sedation OF ANAESTHESIA
or the usual approach that we have. One of The pharmacology of anaesthesia should also
the absolute guarantees is that the animal will include provision of analgesia (which is outside
become recumbent with general anaesthesia and the scope of this article, but will be covered in the
will remain so for the duration that the drugs case examples in the session) as well as the drugs
administered last. The frustration with sedation required to induce anaesthesia. The key point here
is that recumbency is unpredictable and doesn’t is that although you may be performing a procedure
always occur at an opportune moment. under general anaesthesia, it is important to
continue to utilise any local blocks available for the
PREPARATION procedure. It will be beneficial to the animal post-
Assuming that this is not an emergency, this is operatively and also will provide a more stable
key. With-holding food helps to reduce the risk plane of anaesthesia and may allow you to achieve
of regurgitation and post-anaesthetic bloat and a longer period of recumbency and stillness.
improves ventilation:perfusion relationships. The
duration that food should be withheld is slightly When we consider the pharmacological agents
arbitrary and dependent upon the age of animal: available that can be used to induce and maintain
1-2 hours for calves <6 weeks; 6-8 hours for those anaesthesia we primarily have the two licensed
up to 4-6 months and then 24 hours for older alpha-2 agonists, xylazine and detomidine as
animals. The length of starvation for older animals sedatives and then ketamine as an induction
also has the benefit of reducing rumen fill, which agent. Although ketamine is not licensed in the
should help to reduce the challenges of breathing UK, the EMA has stated that no MRL’s are required
when recumbent. as it is metabolised so quickly and is unlikely to
be used more than sporadically. Hereby however
The next important decision is choosing an is the glitch with ketamine – cattle metabolise

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it at a rate and require higher doses than other RECOVERY
species and frequent top-ups. It is however an Once you have completed your procedure, your
excellent analgesic with a wide therapeutic range next challenge is to ensure a safe recovery. Usually
and minimally cardiovascularly depressive, which cattle are more stoic and relaxed than horses and
is of great importance when many of our bovine may take many hours to stand, but when they have
patients are sicker than they appear. We would violent recoveries they are awful! The animal should
ideally combine ketamine with a muscle relaxant be sat and propped up in sternal recumbency with
such as diazepam or midazolam, but neither of straw bales with the head raised in a calm, quiet
these drugs are licensed. enclosed space. If the animal has regurgitated
during the procedure, the mouth should be
Historically other drugs have been used for heavy thoroughly washed out. If the animal is intubated,
sedation such as chloral hydrate or for anaesthesia the tube should not be removed until the animal is
such as thiopentone. Chloral hydrate is NOT an swallowing and ideally removed with the cuff still
anaesthetic agent, is not licensed and has a very partially inflated. If you have administered a lot
narrow therapeutic window – its use in 2021 of ketamine top-ups during the procedure, a low
cannot be recommended. Thiopentone was a very dose of xylazine may be warranted when you start
effective induction and maintenance agent, but recovering the animal. My best advice is to leave
causes significant cardiorespiratory depression and them rather than hurry them to stand. The animal
although once had MRL’s, no longer does and is should receive fibre, but no concentrates for 12-24
not licensed. I cannot see any rationale for the use hours.
of propofol in cattle. It is very short acting, is not
licensed and is respiratory depressive. COMPLICATIONS
Many of the complications I have mentioned above.
We then move onto maintenance of anaesthesia, These include copious saliva production, which
which is yet another challenge to us in the field. should not attempt to be prevented, peri-operative
We have two choices.....top-ups of ketamine and immediately post-operative regurgitation and
or administration of inhalation agents such as post-anaesthetic bloat. This bloat is usually easily
isoflurane. To use isoflurane you need oxygen, remedied, but worth getting farmers to watch-
isoflurane, scavenging and a breathing system and out for. Do not try and prevent during surgery by
either a mask, or preferably an endotracheal tube. passing a stomach tube through the cardia – this
All of these can be mobile to take on farm, but will increase the likelihood of regurgitation and the
require hiring. Intubation is fairly straightforward tube tip will almost never end up in the gas cap!
and has the advantage that there is less risk of Muscle soreness is common, particularly in heavy
inhalational pneumonia from inhaled regurgitation. beef bulls, but myopathies are rare compared with
The key to prevention of regurgitation is having horses. Violent recoveries are luckily unusual, but
the animal appropriately anaesthetised as they even calm recoveries have rarely been associated
are most likely to regurgitate if they are either too with fractures. Calves can become hypothermic,
light or too deep. Top-up’s of ketamine do not last especially if cavities are opened or the animal gets
as long as they would in other species and this unduly wet in cold ambient temperatures, but
can make anaesthesia expensive. Often you will hypothermia in adult animals is rare.
need to top-up every 5-10 minutes. However the
ketamine will last longer and be a more effective MANAGEMENT POST-OPERATIVELY
maintenance agent if it is combined with a good From an anaesthetic perspective, monitoring
analgesic protocol that includes local blocks. for post-operative bloat for the 48 hours and for
coughing or increased respiratory effort associated
MONITORING with likely aspiration pneumonia for 7 days after
At a minimum someone should monitor and the procedure are important to help minimise
record heart and respiratory rate and effort during morbidity and mortality as both can be successfully
surgery. All monitoring performed in other species treated if identified early.
can be performed in cattle. The main difference
when monitoring cattle is that they generally ‘puff’ CONCLUSION
with high respiratory rates after they have received In conclusion, field anaesthesia in cattle is likely to
a combination of an alpha-2 agonist and ketamine. be performed infrequently. However, it is a useful
If maintained on ketamine their eye will be central skill to have for those times when you need it. We
and if they receive an inhalant, the eye will rotate are limited with the drugs we have available, but
ventro-medially. Heart and respiratory rates will
increase with a reduction in plane of anaesthesia.

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safe anaesthetics can be performed with forward
planning. The session at congress will focus on
some cases.

DEDICATION
This article is dedicated to Dr Kate Borer-Weir. She
was a true multi-species anaesthetist whom sadly
lost her life to cancer in 2019, but inspired many
of us with the love for anaesthesia in all creatures
great and small. So her legacy lives on! May she
rest in peace.

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Advanced clinical diagnostics

Mueller, K., IVES, University of Liverpool, Leahurst Campus, Neston, CH64 7TE

ABSTRACT
Utilising diagnostic tools in addition to the physical examination of the bovine patient often allows narrowing
down differential diagnoses or moving from a tentative to a definite diagnosis. Cow-side evaluation of samples
will yield useful information, and additional laboratory examination may be undertaken where indicated. This
article summarises techniques and interpretation of useful diagnostic aids, including liver biopsy, respiratory
tract lavage, rumen fluid analysis, biochemistry profiles, urinalysis and abdominocentesis. Cerebro-spinal fluid
collection and analysis is another useful aid, a description of which may be found in an earlier publication by
the author (Mueller 2017).

LIVER BIOPSY penetration). In adults, the liver is typically reached
Indication at about 20cm depth. Once the liver capsule has
Establish pathology in an individual sick bovine been penetrated, the instrument is pushed into
(for example, fatty liver infiltration, neoplasia, the liver tissue for a couple of centimetres (slightly
photosensitisation); investigation or monitoring of gritty feel to it, like pushing needle through sand)
trace element status on a herd level (in particular and the mechanism of the instrument activated. A
copper). staple or suture is placed into the skin incision.

Restraint and Preparation Potential complications
The animal is restraint standing in a crush or AI stall. Main risk factors include penetration of the gall
It should not be starved to ensure the liver stays bladder and haemorrhage from penetrating a
positioned close to the abdominal wall. Consider large hepatic vessel. Peritonitis is very rare. Post-
assessing clotting ability by collecting blood into procedure dyspnoea caused by a pneumothorax
a plain glass vacutainer; clotting should occur may be seen, but usually resolves quickly.
within 5 minutes in the normal animal. Ultrasound
guidance if desired. Analysis
For copper, blood is washed off the sample with
The site is clipped and surgically prepared. 5ml de-ionised sterile water or saline, before placing
of local anaesthetic is applied subcutaneously and into a plain sampling pot. For histology, the sample
into the intercostal muscles. Sedation is usually not is placed into 10% formalin. Normal liver copper
required. levels are 300–8000 μmol/kg dry matter (or 95–
2000 μmol/kg wet matter). For herd monitoring, 5
Technical description animals are sampled and the mean taken.
The insertion point is in the right 11th intercostal
space (i.e. second but last space) on a line drawn BRONCHO-ALVEOLAR LAVAGE AND
between the tuber coxae and the shoulder joint TRANSTRACHEAL WASH
(or about 15cm ventral to the lumbar transverse Indication
processes). A stab incision is made into the skin Identification of pathogens involved in bovine
and into part of the intercostal muscle. With the respiratory disease. Cytology for respiratory tract
wrist resting on the animal, the biopsy instrument pathology in general.
(Tru-Cut®, spring-loaded or other liver biopsy
needle/trochar of 14 gauge or 4mm OD, 25–30cm Restraint and Preparation
length) is advanced either perpendicular to the Standing restraint in a crush under mild to moderate
skin and aiming straight across the abdomen, or sedation, and head restraint with halter and
pointing cranio-ventrally towards the contra-lateral assistant to further restrain and position head. For
elbow. Appreciating the tissue layers during steady trans-tracheal wash (TTW), the site is clipped and
advancement is important: these are intercostal disinfected, and a bleb of local anaesthetic made.
muscle, pleura (resistance followed by a ‘pop’), For broncho-alveolar lavage (BAL), the muzzle and
diaphragm (slight ‘pop’; needle will move strongly nostril is dry-wiped and lidocaine gel applied to the
with each breath once in diaphragm) and liver nostril and tip of the BAL tube. Attach a 3-way tap
capsule (third ‘pop’ about 1–2cm after diaphragm

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to the BAL tube. It is helpful to mark the following ANALYSIS
distances on the tube with a marker pen: nostril If multiple aliquots were recovered, these are
to larynx, and nostril to point of shoulder (which combined in a sterile receptacle and mixed. For
roughly corresponds to level of bifurcation). cytology, two air-dried smears are prepared
cow-side and 3-5ml of fluid placed into an EDTA
Technical description vacutainer. One or two plain vacutainers are
TTW: a small stab incision is made over the midline filled with recovered fluid for pathogen isolation
of the ventral trachea halfway down the neck. The procedures, and promptly submitted to the
trachea is stabilised with one hand, and a short laboratory (ideally chilled). It is useful to consult the
12-14 gauge hypodermic needle fully inserted laboratory re the need for virus transport medium.
between two cartilage rings, angled 30-45 degrees
downwards. A fine tube (for example, 5Fg dog RUMENOCENTESIS
catheter or human central venous catheter like Indication
Centracath 75) is inserted through the needle and Diagnosis and monitoring of SARA (sub-acute
advanced towards the bifurcation. 20 or 40ml (calf rumen acidosis) on a herd level. Diagnosis of
/adult) of sterile saline is injected and immediately rumen indigestion or acute carbohydrate overload
aspirated. If less than 5ml of fluid is recovered, a in individual cattle.
second aliquot of saline is injected and aspirated.
The author prefers to remove the tube jointly with Restraint and Preparation
the needle (rather than tube first, then needle). Standing restraint, with manual restraint for calves
or crush/gate/AI stall for older cattle. Sedation and
A modified technique is a trans-tracheal aspirate, local is not required. A pain response or resentment
whereby 20ml of sterile saline are injected and to needle penetration of skin and peritoneum is
aspirated through the needle – without the use of likely – anti-kick measures are useful as well as
a tube. The recovery of sufficient sample volume is careful positioning of oneself.
less likely with this technique, though.
For routine monitoring, ideal sampling time is 3
BAL: field BAL involves passing a BAL tube (300cm hours after morning feeding.
length, 10mm outer diameter, 2-3mm internal
diameter, cuffed) blindly into the a bronchus The site is clipped and surgically prepared.
(as opposed to using an endoscope). The tube is
inserted into the ventral meatus and advanced Technical description
to the point of the larynx. The animal’s head is A 18-20 gauge hypodermic needle (5cm/2” for
elevated and extended and at point of inspiration, dairy cattle or 7.5cm/3” for well-conditioned beef
the tube is advanced into and down the trachea animals) is inserted perpendicular to the skin and
until becoming lodged in a bronchus. For patient advanced fully up to the hub – either about a hand-
comfort, consider instilling 10-20ml of lidocaine width behind the last rib in the lower third of the
each at the point of the larynx and in the ventral flank, or in the left ventral abdomen behind the
trachea (via the BAL tube). Inflate the cuff (typically xiphoid cartilage. Suction is applied with a 20ml
5ml of air required) and inject 3x 20ml (calf) or 3x syringe and 10-20ml of fluid collected into a plain
60ml (adult) of sterile saline, sealing off the tube universal container.
using the 3-way tab during syringe change-overs.
Fluid may either be aspirated after each aliquot or Potential complications
after all three aliquots. Localised peritonitis is possible, but complications
are overall rare and of limited severity.
Potential complications
With TTW, accidentally cutting off the catheter Analysis
during removal. It usually is coughed up rather than 1) Colour: green with grass diets, brownish-yellow
aspirated. Where an animal is in severe respiratory with straw or maize silage diets.
distress, BAL may exacerbate the dyspnoea.
Coughing during insertion of the TTW catheter Abnormal colours include: milky-grey indicating
may result in the tip being flipped into the proximal acidosis; light brown indicating simple inactivity;
trachea, resulting in a non-representative sample. dark brown to black indicating decomposition of
Directing the needle downwards will reduce this rumen contents.
risk.
2) Odour: Normally aromatic, partially resembling
diet components.

Abnormal odours include: acidic indicating

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carbohydrate overload or abomasal reflux; stale at body temperature and using a warm
indicating simple inactivity; ammoniac indicating slide, moving about actively. In digestive
urea poisoning; repulsively musty or foul indicating disorders, the large protozoa are the first to
protein decomposition. disappear.
b. Gram stain of an air-dried smear. In normal
3)pH (using pH indicator paper (ideally with 0.2 unit fluid, gram -ve bacteria prevail, and there
increments) or pH meter): Normally between 5.5– is a large variety of shapes and sizes.
7.0, however this is diet dependant. Animals on a Uniformity of bacteria indicates a diet rich
roughage-rich diet will show a reduction to about in starches or a digestive disorder. In cases
6.2 between 3–4 hours after feeding. Animals on with acidosis, gram +ve bacteria prevail and
a concentrate-rich diet will show a reduction to rod-shaped lactobacilli may prevail.
5.5 about 3 hours after feeding. An apparently
normal pH should also be interpreted in light of BIOCHEMISTRY PROFILE
case history: for example, a pH of 6 in an animal A summary overview of useful biochemistry tests
inappetent for the last 24 hours is abnormally low. and their interpretation in cattle is provided:
Abnormal pH values include: alkaline (7.5–
8.5) indicating starvation for >24 hours, simple Albumin and Globulin
inactivity of the rumen flora, urea poisoning, Reduced albumin may indicate renal or GI-tract
protein decomposition; acidic (<5.5) indicating loss, reduced production by the liver, insufficient
carbohydrate overload or reflux of abomasal fluid. dietary protein or utilisation of dietary protein for
energy provision, loss into third space (interstitial
4) Sediment activity time, based on observation compartment).
of fresh fluid in a cylindrical container. Normally,
fine food particles and protozoa will sink, while Low levels of both albumin and globulin indicates
larger and fibrous material is carried to the surface, protein loss in the GI-tract, for example from a
and this process takes 4–8 minutes to complete. parasite burden (especially coccidiosis) or Johne’s
A distinct greyish layer at the bottom of the tube disease.
indicates large protozoa are present and the sample
is active. Elevated globulin may be seen with inflammatory
processes. This may be more a function of the
Abnormalities include: rapid sedimentation with test including acute-phase proteins, as most
slow or absent flotation indicating starvation, laboratories will determine globulin by substracting
acidosis or simple inactivity; rapid flotation or albumin from total protein measurements (rather
particles remaining in suspension indicating a than measuring globulin direct).
concentrate-rich diet or protein decomposition.
Renal failure
5) Methylene blue reduction test: 20ml of warm Renal insufficiency typically leads to:
fresh rumen fluid is added to 1ml of 0.03%
methylene blue. A second tube or container is • Increased blood concentrations of
filled with plain rumen fluid for colour comparison magnesium and phosphorus, as well as
and the time measured until the stained sample is urea and creatinine.
decoloured again. Normally, this takes 1 minute on
a pure concentrate diet, 3 minutes on a mixed diet, • Decreased blood concentrations of calcium,
and 3–6 minutes on a hay diet. sodium, chloride and often potassium. Also
an abnormal sodium to potassium ratio.
Decolouration taking >6 minutes is abnormal
and indicates poor activity of the microflora, for • Metabolic alkalosis in acute stage, followed
example because of acidosis, starvation, or a ration by shift to acidosis in terminal stage.
deficient of effective fibre.
• Dehydration (i.e. blood concentration/
6)Follow-up examination in the practice includes: elevated haematocrit).
a. Microscopic examination for protozoa. One
drop of rumen fluid is placed onto a slide • Hypoproteinaemia in terminal stage.
and a coverslip added, then examined
with 80–100 magnification (10x objective). The following serum values have been suggested as
Large, medium and small protozoa should a guideline for a poor prognosis in cattle:
be present and, if the sample has been kept Magnesium > 3.5 mmol/l
Phosphate > 2.9 mmol/l
Creatinine > 130 mmol/l
Urea > 16.5 mmol/l

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Renal function tests: Interaction between analytes
• Serum urea to creatinine ratio is less clear- Possible interactions between analytes must be
cut in ruminants cf. other species because considered. A common example is dehydration
of their ability to recycle urea. leading to falsely elevated blood concentrations
• Fractional excretion of electrolytes of other analytes. As another common example,
(comparing creatinine concentration with low blood albumin levels often result in low blood
that of electrolytes) varies depending on calcium levels. However, ionised calcium is not
the diet (for example, grass versus hay or affected, and therefore this rarely is of any clinical
concentrate feeding). relevance.

Liver pathology Even mild haemolysis can lead to spurious
Gamma-GT is regarded as a reasonable indicator of elevations in AST. In contrast, haemolysis can
bile duct pathology (especially obstructive disease) suppress bilirubin levels.
and chronic lesions, and GLDH as a useful indicator
of acute or ongoing liver parenchyma damage. For URINALYSIS
both, the author would not be overly concerned Indication
unless normal levels are increased by at least Suspected urinary tract disease, but also metabolic
8-10 fold. It is thought that at least 30% of liver disease like ketosis and to monitor effectiveness of
parenchyma has to be damaged before a rise in liver a DCAB (dietary cation-anion balance) ration.
enzymes is likely. SDH is also reasonably specific to
hepatocellular damage. Both GLDH and SDH rise Restraint and Preparation
quickly after an insult and have a short half-life. In Manual restraint for calves, crush/gate/AI stall for
the neonate, most circulating gamma-GT is likely to adults. In females, the perineal area is dry-wiped
have originated from colostrum. for normal urinalysis. If culture is performed on a
voided sample, disinfection of the perineal area
GOT and AST are not liver specific with muscle cell is recommended. In males, long preputial hair is
damage being another common source of elevated trimmed with scissors.
blood levels. Therefore, it requires interpretation
with other enzymes to pinpoint their source. Both Technical description
enzymes may take a few days to reach peak levels Female: For a voided sample, the perineal area is
after an insult. stroked without holding the tail or disturbing the
cow in any other way. For catheterisation, a sterile
If offered by the laboratory, elevated bile acids mare urinary catheter, lubricated with KY Jelly, is
are a useful indicator of liver disease in the young gently inserted into the urethral opening (located
calf. In all ages, elevated levels indicate liver on the ventral vaginal floor about 8–10cm cranial
dysfunction, however the specific link to fatty liver to the vulval lips) and advanced, taking care not to
infiltration is probably unfounded (and bile acid can become lodged in the sub-urethral diverticulum.
fluctuate considerably in normal adult cattle).
Male: Gentle stroking of the perineal area
Musculo-skeletal disorders or sigmoid flexure is successful in some males.
Creatine kinase (CK) and AST are good indicators Stimulation techniques used in the stallion (e.g.
of musculo-skeletal disorders in cattle, in particular whistling, running water, shaking up bedding)
muscle damage. Elevated levels are commonly seen are rarely successful in the bull. Catheterisation
in white muscle disease or tetanus. For prognosis, is extremely difficult in the bull because of the
the shorter half-life of CK over AST is useful: for sigmoid flexure and sub-urethral diverticulum.
example, a further elevation of CK between samples
taken 48-72 hours apart suggests ongoing muscle Potential complications
damage, whereas a continued elevation of AST Introduction of infection during catheterisation.
often reflects the longer half-life of this enzyme.
If no further muscle damaged occurred, CK levels Analysis
would be expected to have fallen markedly within For culture, urine is collected into a sterile sample
2-3 days after the insult. pot. For other analysis, a dipstick may be held
directly into the urine stream, or urine is collected
Bone pathology, such as in osteodystrophies, may into a universal container.
lead to elevated alkaline phosphatase, sometimes
with concurrent reduced blood calcium levels. A human urine dipstick is useful for on-farm
assessment. However, it is not accurate for specific
gravity and this should be determined with a

2021 83

CATTLE PRACTICE VOLUME 29 PART 1

refractometer. For DCAB herd monitoring, pH crush/gate/AI stall for older cattle. Sedation and
indicator paper or a pH metre is often more useful local anaesthetic is typically not required. A pain
than a dipstick because of their finer graduation. response or resentment to needle penetration of
skin and peritoneum is likely – anti-kick measures
Normal parameters are: Alkaline with pH 7.0 to 8.0; are useful, as well as careful positioning of oneself.
specific gravity 1.020 to 1.040 (may be below 1.020
in high-producing dairy cows); low concentrations Technical description
of Na, Cl, P, Ca, Mg; high concentrations of K; trace In ruminants, most suitable sites for collection are:
of protein; small amount of ketones. Crystalluria (1) left paramedian, one hand-width behind elbow
is not significant unless a very large amount is of animal; (2) left or right paramedian, just in front
present; calcium-carbonate and triple phosphate of udder (taking care to avoid milk vein). A 18-20
crystals are common in normal urine. gauge hypodermic needle (5 cm/2” for dairy cattle,
6.25–7.5cm/2.5–3” for high BCS beef cows or bulls)
Possible changes and their causes include: is inserted perpendicular to the skin and advanced
• pH can rise with some bacterial infections, until fluid appears. If fluid is not forthcoming,
but usually falls with urinary tract disease suction using a 10ml syringe may be tried or the
• Cattle may show paradoxic aciduria, where needle slightly repositioned. Choice of site (1) or (2)
urine pH is acidic despite the animal depends on whether a localised cranial or caudal
suffering metabolic alkalosis. problem is suspected. For generalised problems,
• Specific gravity <1.020 and no change either site is suitable. However, the omentum is
despite water deprivation or administering very effective in sectioning off fluid, and sampling
large quantity of water indicates renal at two or three sites or depths may be necessary
insufficiency. to obtain a sample, or ultrasound guidance is used.
• Proteinuria indicated renal compromise. It
can have physiological causes (stress like Potential complications
recent transport, fever, heavy lactation). Overall rare and of limited severity. Puncture of
May get false positive with human dipsticks viscera is possible, but a needlepoint defect typically
in alkaline urine. seals quickly. Therefore, unless the animal moved
• Bacteria – Direct counts: < 10,000 bacteria/ markedly during sampling, potentially causing
ml = contamination; 10,000 to 100,000 = laceration of a structure, no action is required.
questionable; > 100,000 = infection.
• Glycosuria: Enterotoxaemia due to Cl. Where clinical impression suggests abnormal
perfringens type D; diabetes (very rare in fluid is likely present, but a sample cannot be
cattle) obtained, the clinical impression should be trusted.
• Haematuria: Blood clots or discoloration
or brown sediment; microscopy confirms Analysis
presence of RBC; usually also positive for The sample is divided between a small EDTA
haemoglobin on the dipstick. Rule out (cytology and protein) and plain (culture) sample
contamination from reproductive tract in tube. Normal peritoneal fluid is straw-coloured and
cows, especially if recently calved. clear. In late pregnancy, peritoneal fluid is often
• Haemoglobinuria: false positive result copious, slightly cloudy, and may clot. Visually
possible caused by lysed RBC (use detectable abnormalities include: volume greater
microscopy to ascertain). than 10ml indicating pathology (or late pregnancy);
• Myoglobinuria: due to myopathies; fibrin or clotting indicating inflammation; ingesta or
differentiate from haemoglobin by green discolouration indicating rupture or needle
spectrography and absence/presence of penetration of GI tract; red or pink discolouration
raised muscle enzymes. or blood (with or without blood clots) indicating
haemorrhage or puncture of vessel during
ABDOMINO-CENTESIS collection; reddish-brown fluid indicating gut
Indication necrosis. The sample is shaken vigorously to check
To rule in or out peritonitis, internal haemorrhage, for elevated protein levels – if present, a stable
rupture of a portion of the gastro-intestinal tract, head foam will form (note: a second aliquot should
uroperitoneum. be used for this, because it will render the sample
unsuitable for running through an analyser).
Restraint and Preparation
Standing, with manual restraint for calves or Follow-up analysis in the practice includes:
protein concentration (refractometer or analyser),

2021 84

CATTLE PRACTICE VOLUME 29 PART 1

cell count (smear stained with Diff-Quik), bacterial
contents (examination of smear and culture).
Normal protein levels are <30g/l. Normal nucleated
cell count is <6,000/ml (PMNs/granulocytes).
Degeneration of PMNs indicates infection.
A creatinine concentration of 1.5–2 times or
more the animal’s serum level is indicative of an
uroperitoneum.

REFERENCES

Mueller, K. (2017) Farm animal diagnostic tools. Cattle
Practice 25: 101-105

2021 85

CATTLE PRACTICE VOLUME 29 PART 1

Benchmarking Antibiotic Usage & Ending
Neonatal Prophylaxis On Sheep Farms In Devon

Jonathan Hobbs, North Park Veterinaray Group Ltd, North Tawton, Devon, UK

BACKGROUND:

Mg/PCU antibiotic Overall use is low However we have Notably prophylaxis and whole-
usage in UK sheep within the sheep flock treatments, including the
flocks identified in recognised areas blanket treatment of neonates
industry requiring
20171
improvement

OBJECTIVES: METHODS: Ensure ALL
practice staff
1: Quantify mg/PCU usage Amend Lift annual are with you
on flocks within a practices if
discussion group and required antibiotic Engage with ALL
compare to national sales from farmers
average practice data
Educate
2: Benchmark discussion Feedback & Obtain farmers,
group farms to facilitate benchmark provide realistic
change if required livestock & feasible
numbers options
3: End the blanket use of from client
oral spectinomycin in Set achievable
neonatal lambs Calculate goals
mg/PCU
Maintain
Circular flow demonstrating the constant cycle contact and
required to meet objectives 1 and 2, reviewed
at least annually. Step flow process to end neonatal review
prophylaxis.

RESULTS: CONCLUSIONS:

Figure one: Total mg/PCU of antibiotics by year and flock in discussion group • It is possible to end the blanket use of
antibiotics in neonates on sheep farms.
Year Number of Total number of Total number of lambs Mean flock Median flock Range of flock
flocks breeding ewes reared (sold or retained mg/PCU • It was a major change for most farmers and
2016 mg/PCU mg/PCU they were concerned about the impact.
2017 13 7922 for replacements) 14 Small steps were taken in year one. After
2018 15 8838 13.17 14.05 1.97-33.63 gaining confidence, greater progress was
15 8794 13005 13.86 13.02 1.83 - 22.02 seen in year two.
13.43 2.55 - 26.71
14455 • Engaging with farmers regarding their
usage of antibiotics is rewarding work.
14218 Potential lost revenue from loss of drug
sales is replaced by service (vet time)
Figure two: Descriptive statistics of reported flocks by year revenue.

Spectinomycin usage by all flocks under the care of North Park Veterinary Group: • Benchmarking farmers is a useful tool for
facilitating discussion and driving change.
• Total sales FELL by 14% from 2017 – 2018
• 47.6% of farms reduced usage; 34.6% no change; 17.8% increased • These models can and should be replicated
by all veterinary practices working with any
• Total sales FELL by 54% from 2018 to 2019 livestock enterprises (sheep, beef or dairy).
• 67% of farms reduced usage; 15% no change; 18% increased This model should help all stakeholders
safely reduce antibiotic usage.
• There were no negative consequences to lambs reported in association with
this reduction. SUPPORTED BY:

REFERENCES: 1.Davies, P., Remnant, J. G., Green, M. J., Gascoigne, E., Gibbon, N., Hyde, R., Porteous, J. R., Schubert, K., Lovatt, F.,
Corbishley, A. (2017). Quantitative analysis of antibiotic usage in British sheep flocks. The Veterinary Record, 181(19), 511.

2021 86

CBATCTLSE PRaACnTIdCE Fertility VOLUME 29 PART 1

Low body condition score in autumn-calving heifers associated with
return to first service but not pregnancy at the end of breeding

A. Knight and S.C Archer - University of Surrey

681 Holstein/Friesian heifers Body condition score (BCS) and mobility
recruited at calving over 2 score assessed between 0 and 30 days
weeks at 15 farms in milk by a single observer (AK)

Start of 13 heifers lost to 610/668 (91 %) of calved heifers
service follow up served within 3 weeks of the
start of breeding; 655/668 (98%)
Mean Returned to served within 6 weeks
service first service
period after at least 644 heifer did not
=59 days 10 days return to 1st service
(assumed in calf)
22/668 2 or more
End of heifers AI serves
service
period

Pregnancy diagnosis by trans-rectal ultrasound at least 30 days after end of
service period

For context, increase in early Infographics of 10 heifers Return to first service
lactation BCS by 0.5 for 10 Assumed pregnant
heifers would be required for Average BCS 3
1 less return to 1st service. Average BCS 2.5

Denominator Exposures Outcome Statistical Results
approach
of interest No association with exposures of
Mixed effect interest identified (p>= 0.05)
No difference end of of logistic
681 csaelvrevdice pBeordiyod pdFirstsstaerrtviocfesweritvhicine 3 weeks of No association with exposures of
heifers (pc>o=nad0nid.t0io5n) period regression interest identified (p>= 0.05)
681 calved First service within 6 weeks models.
(odds ratio = 0.41 (95% CI; 0.37 to
heifers mobility start of service period 0.45); p = 0.03).

668 served score 0 to 2 or more services (over 10 days No association with exposures of
interest identified (p>= 0.05)
heifers 30 days in apart) recorded

668 served milk Diagnosed pregnant at scan

heifers

• A low prevalence (9/681) of early lactation lameness was detected in primiparous cows in the

autumn-calving herds studied.

• An association was identified between BCS and return to first service, although any association

with pregnancy was diminished by the end of the two-month breeding period.

• Further research is required to determine if interventions to transition cow nutrition and

management would be cost effective on these farms.

INSPIRE student research grant (University of Surrey) [email protected]
Ruminant research bursary (MSD Animal Health) [email protected]

2021 87

CATTLE PRACTICE VOLUME 29 PART 1

MSD ANIMAL HEALTH

Identification of BRD antibodies to install an adapted BRD
vaccination program on Dutch dairy farms

Henk Kuijk1, Katharine Baxter-Smith2, Hanny Swam1, Pleun Penterman1, Geert Vertenten1

1MSD Animal Health, Boxmeer, The Netherlands; 2MSD Animal Health, Milton Keynes, United Kingdom

OBJECTIVES complex, mainly combined with Mh. On farms with presence of mainly
viral pathogens in the very young animals, an intranasal vaccination with
Bovine Respiratory Disease (BRD) is a multifactorial disease of young a live BRD vaccine was recommended (Bovilis® INtranasal RSP™ Live).
and growing cattle. The factors that predispose to BRD include stress This could be followed by vaccination with a trivalent inactivated vaccine
related to stocking, moving or mixing cattle, poor ventilation or draughts, (Bovilis® Bovipast RSP) at a later age, mainly if the samples were positive
sudden climatic changes or extreme heat or cold, mixing various age for Mh antibodies in calves at weaning age or older (> 2 months).
groups, nutritional deficiencies, colostrum deficiency, and poor feed 16% of the BRD QuickScans were positive for Mycoplasma bovis. On
hygiene. These stresses lead to infection by primary viral pathogens Mycoplasma bovis farms, a specific approach was recommended as no
which cause lung damage. The viral damage to the lungs may pave the commercial vaccines are present. It was advised to check the serological
way for various bacterial pathogens as Mannheimia haemolytica (Mh) status of the adult cows, create small groups of animals, avoid mixing
and Mycoplasma bovis. of calves from several groups and to vaccinate against other BRD
pathogens found.
Vaccination is an important tool in managing BRD. Identification of major After the implementation of the BRD prevention plan including the
respiratory pathogens on a BRD problem farm may be essential to BRD QuickScan, 46 farms started vaccinating with an inactivated BRD
establish an appropriate vaccination program. vaccine (Bovilis Bovipast RSP), 5 started with a live intranasal BRD
vaccine (Bovilis INtranasal RSP Live) and on 5 farms complementary
In 2019 MSD Animal Health started a BRD Prevention Plan including examinations were performed.
a serological screening, the BRD QuickScan, to identify which BRD
pathogens are circulating on a farm. The BRD Prevention Plan is a Figure 1. Presence of 4 major BRD pathogens in calves on 56 dairy farms in the Netherlands (Oct-Dec 2019)
decision tree guiding veterinary practitioners to manage BRD. Depending
on the results of the BRD QuickScan, a tailor-made advise including BRD CONCLUSION
vaccination and improvement of BRD management factors is given
For most pathogens circulating on BRD farms vaccines are
This poster gives an overview of the first results of the BRD Prevention commercially available. Implementing a farm-adapted BRD
Plan and QuickScan on Dutch BRD problem farms not vaccinating management program including vaccination is important to reduce BRD
against BRD. related losses. Practical tools as the BRD Prevention Plan and BRD
QuickScan may be useful to reduce BRD. Based on serological findings
MATERIAL AND METHODS farmers can easily decide (in dialogue with their vets) to vaccinate
against BRD.
To run the BRD QuickScan, serum samples were taken from 5
calves (3-6 months old) on a BRD problem farm or BRD suspected KEYWORDS
farm. Those samples were analysed in the Centre for Diagnostic
Solutions (MSD Animal Health, Netherlands) for antibodies against Mh, Bovine Respiratory Disease, QuickScan, serology, dairy, Netherlands
Bovine Respiratory Syncytial Virus (BRSV), Parainfluenza 3 (PI3) and
Mycoplasma bovis by ELISA. An in-house test was used to measure Bovilis® Bovipast® RSP contains inactivated BRSV (strain EV908), Pi3 virus (strain
Mh and BRSV antibodies, whereas for PI3 and Mycoplasma bovis a SF-4 Reisinger) and inactivated Mannheimia (Pasteurella) haemolytica (serotype A1).
commercial kit was used from respectively IDEXX and Bio-X. The results POM-V
of samples collected between October 18th to December 31st, 2019 are Bovilis® INtranasal RSP™ Live contains live BRSV and Pi3. POM-V
presented. Further information is available from the SPC, datasheet or package leaflet. MSD
Animal Health UK Limited. Registered office Walton Manor, Walton, Milton Keynes
RESULTS MK7 7AJ, UK. Registered in England & Wales no. 946942. Advice should be sought
from the medicine prescriber.
During the defined timeframe, 56 BRD QuickScans were performed. Use Medicines Responsibly.
In 9% of the BRD QuickScans, no significant antibodies against the © 2021 MSD Animal Health UK Limited.
selected BRD pathogens were identified. In those farms, a tailor-made
approach was provided to improve the BRD status (www.rescalf.nl).

Seventy-two percent of the QuickScans were positive for antibodies
against Mh, 11% of the QuickScans had only Mh antibodies, where in
66% of the QuickScans antibodies against Mh and viral BRD pathogens
(BRSV and/or PI3) were present. None of the samples had a mixed
Mh-Mycoplasma bovis antibody presence. On farms positive for Mh,
vaccination with a vaccine providing protection against Mh
(Bovilis® Bovipast RSP) was advised. If BRD (including Mh) played a
major role in very young animals, vaccination of pregnant dams was
advised to provide Mh protection to the very young calves.

Seventy-three percent of the QuickScans were positive for BRSV and/
or PI3. Three percent of the QuickScans were only positive for PI3
antibodies and none were only positive for BRSV antibodies. These
findings confirm the importance of the viral pathogens in the BRD

MSD Animal Health

Copyright © Intervet International B.V., also known as MSD Animal Health.
All rights reserved. BCVA 2021 Poster

2021 88

CATTLE PRACTICE VOLUME 29 PART 1

A study of the factors that influence career choices of

veterinary undergraduate students at a UK university
Erin Loogman and John Fishwick

Royal Veterinary College, University of London, Hatfield, AL9 7TA

[email protected] and [email protected]

Background Results

• A perceived shortage of farm veterinarians • 482 students responded to the survey
has been recognized in the UK and other
developed countries for many years. • 405 (84%) of the respondents were female, 73 were male (15.1%) and 4 (0.8%) respondents
preferred not to specify
• This workforce shortage could lead to a
loss in essential services involving Current sector of employment of UK veterinarians and RVC student career Figure 1: Student
livestock production, veterinary public interest in each sector
60 52.6 51.4 preferences outweighed current

health, food safety, disease control and 50 employment in every

surveillance all of which could affect food Percentage 40 sector, except for small

security and pose serious animal health 30 25.1 11.6 5.5 8.5 animal/exotic practice,
and welfare issues. 20 11.7 3.2 which was almost equal
• The aims of this study are to determine: 10 in value.

• If student background affects students’ 2.9 3.3

0

interest in entering farm/mixed practice Small animal (including Mixed Practice Farm Practice Equine Practice Other
exotics)

• Current interest of students in Practicing veterinarians (Robinson et al 2019) RVC students

farm/mixed practice compared to Figure 2: Likert scale

current employment in each sector data with factors of
• What factors are most important to importance to RVC
students when selecting
students when selecting a new graduate a new graduate
job, and, if one or more are not met, job. Students were
would they consider leaving that sector asked to rate the

Methods following from 1-5 with
‘1’ being not at all
• A cross sectional survey was granted ethical important, ‘2’ being
approval by the Royal Veterinary College slightly important, ‘3’

(RVC) Social Science Research Ethical being moderately

Review Board (SSRERB) (URN: SR2020- important, ‘4’ being
0138) before being released considerably important,
• It was sent to years 1-5 and graduate and ‘5’ being very
accelerated RVC BVetMed students important. Students most
• A chi-squared analysis examined the frequently chose
relationship between categorical responses. ‘support and
mentorship’as ‘being

Results very important’followed
by ‘geographical

Table 1: Results of Chi-squared analysis location of the
of students that showed interest in practice.’

pursuing a career in farm or mixed practice

compared to various personal factors or

experiences. Responses considered

significant (P<0.05) are shown below.

Factors that increase the likelihood P value
of choosing to be farm/mixed vet:

Being Male P=<0.0001

Growing up in a rural area P=0.0127

Being from a Family Farm P=<0.0001

Previous paid/unpaid work on farms P=<0.0001 Figure 3: Additional comments from students with

Previous farm employment P=<0.0001 factors important to selecting a new graduate job. Figure 4: Reasons expressed by students on why they

Completing a non-veterinary P=<0.0001 The most important considerations includes ethical might change sectors of veterinary medicine. The most
agriculture degree
considerations/charity work, followed by ethnic frequently cited concern from students was lack of

Students who always/sometimes P=<0.0001 diversity and acceptance, future career opportunities, support and mentorship followed by insufficient wages
enjoyed farm teaching compared to
students that never enjoyed farm and time spent with a particular species. and benefits.
teaching
Discussion and Conclusion

Students who choose to complete 4 P=<0.0001 • Being male, from a rural area, having farm and livestock experience, and farm animal teaching
weeks or more of farm/mixed EMS at the RVC all encouraged students to enter farm or mixed practice.

Students who feel encouraged by P=<0.0001 • RVC student interest in mixed and farm practice is higher than the number of vets currently
RVC farm teaching/placements employed in these area. This indicates there is enough interest from graduates to fill the current
need in the industry
Students who are considering an P<0.0001
• Students most often chose ‘support and mentorship’ as being ‘very important’ when choosing a
internship/post graduate qualification new graduate job.

in farm animal medicine • Students most frequently cited that insufficient support, and low wages and benefits would be
likely to cause them to potentially reconsider their career choice or sector of practice.
Reference: Robinson D, Edwards M, Mason B, Cockett J, Graham K, Martin
A. (2019). The 2019 survey of the veterinary profession. Royal College of
Veterinary Surgeons.

2021 89

CATTLE PRACTICE VOLUME 29 PART 1

MannheiMia haeMolytica serovars
associated with respiratory disease

in cattle in Great Britain

colin Mason,1 Jane errington,1 Geoffrey Foster,2 Jennifer thacker,3
oliver Grace3 and Katharine Baxter-smith4

1. SRUC Veterinary Services, St Marys Industrial Estate, Dumfries DG1 1DX 3. SRUC Veterinary Services, Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ
2. SRUC Veterinary Services, An Lochran, 10 Inverness Campus, Inverness IV2 5NA 4. MSD Animal Health, Milton Keynes MK7 7AJ

BacKGround: Mannheimia haemolytica is commonly associated with respiratory disease in cattle worldwide as a
cause of fibrinous pneumonia, bronchopneumonia and pleuritis.1 The study aim was to determine the most common
serovars of M. haemolytica associated with respiratory disease in British cattle. Knowledge of these serovars could
assist veterinary surgeons with preventative vaccination choice.

Method: M. haemolytica isolates from 104 bovine clinical pathology and post-mortem samples a1 a6
isolated from pneumonia cases between 2016-2018 were tested using a multiplex PCR assay to a2
identify M. haemolytica serovars A1, A2 and A6.

8.7% results: Forty-six isolates (44.2%) typed as M. haemolytica serovar A1.
17.3% Thirty-one isolates (29.8%) as M. haemolytica serovar A2.
44.2% Eighteen isolates (17.3%) as M. haemolytica serovar A6.
29.8% Nine isolates (8.7%) were not A1, A2 or A6 so were considered
to belong to other serovars or were not typable.

conclusions: This study highlights the importance of M. haemolytica serovars other than A1 which may
be responsible for respiratory disease in cattle. Currently, only one cattle BRD vaccine is licensed in the
UK to protect against M. haemolytica serovar A6, in addition to A1. This information could help guide the
veterinarian when making choices on preventative vaccination.

Additionally, the proportion of isolates of serovar A2 as a primary component of respiratory disease in UK
cattle was considered a novel finding as this serovar has not previously been associated with respiratory
disease in cattle.2

References: 1. Rice JA, Carrasco-Medina L, Hodgins DC, Shewen PE (2008) Mannheimia haemolytica and Bovine Respiratory
Disease. Anim Health Res Rev 8:117-128. 2. Fodor L, Varga J, Hajtos I, Szemeredi GY (1984) Serotypes of Pasteurella
haemolytica isolated from sheep, goats and calves. Zoonoses Public Health 31:466-469.
Bovilis® Bovipast® RSP contains inactivated BRSV (strain EV908), Pi3 virus (strain SF-4-Reisinger) and inactivated Mannheimia
(Pasteurella) haemolytica (serotype A1). poM-v. Further information is available from the SPC, datasheet or package leaflet.
MSD Animal Health UK Limited. Registered office Walton Manor, Walton, Milton Keynes MK7 7AJ, UK. Registered in England
& Wales no. 946942. Advice should be sought from the medicine prescriber.
use Medicines responsibly.
© 2021 MSD Animal Health UK Limited.
UK-BoV-210900001

4068 Bovipast RSP BCVA Poster_A4.indd 1 08/09/2021 09:50

2021 90

CATTLE PRACTICE VOLUME 29 PART 1

BVD vaccination and surveillance protocol for a large,

multisite, all year round calving dairy herd

James O’Hara, Tom Clarke

Synergy Farm Health, West Hill Barns, Evershot, Dorset, DT2 0LD

Summary

There is a high risk of compliance challenges when designing a BVD vaccination and monitoring protocol for all year round calving dairy farms with
multiple milking and rearing sites (Meadows, 2010). Vaccination protocols beginning at 5-6 months of age can achieve elimination of BVD if used
in conjunction with BVD tag testing of all calves in combination with check testing. Vaccination of dams with a live BVD vaccine did not appear to
interfere with BVD antibody surveillance in heifer calves sampled at 5-6 months old.

Introduction

A 2000+ cow multisite dairy farm in the south west of England identified presence of BVD during a routine youngstock BVD antibody screening
following a breakdown of the previous vaccination protocol. This poster highlights the challenges faced and resulting protocol put in place.

Background Figure 1. Current youngstock management protocol

Calves are born on 3 dairy units and reared on 1 large calf unit. At Developing a control protocol
6 months old, calves move to multiple rearing locations and then
to one of 4 breeding sites. Animals arrive anytime up to 2 weeks For testing and vaccination purposes, two consistent locations that all
pre-breeding which starts at 11 months/380kg BW. Bred heifers heifers pass through are the calf unit (exiting at 6 months old) and the
then move to one of 4 different sites or grazing depending upon transition pens (entering at 20-21 months old) and both units have skilled
season, before re-joining transition pens back at the dairy units 3- staff and adequate handling facilities. See Figure 1.
4 weeks pre-calving. - Taking surveillance BVD antibody blood samples at the calf unit is earlier
than the recommended 9-18 months to avoid MDA interference but
Challenges of large multi-site operations avoids interference of antibodies from vaccination.
- Vaccinating at 6 months old is younger than ideal to complete a vaccine
• Timing vaccination courses consistently prior to mating, course to protect for BVD through the entire pregnancy, however this
particularly to ensure BVD protection for the crucial 1st early vaccine protocol achieves maximum compliance and using a live BVD
trimester to prevent creation of PI animals vaccine ensures foetal protection against BVD through the first trimester.
This was administered concurrently with other vaccines to achieve the
• Keeping track of cohorts of heifers with multiple sites and staff required protection against a number of other infectious diseases.
so that no animals miss full primary vaccination course The farm began BVD tag and testing all (dairy heifer and bull, beef and
dead/aborted) calves.
• Ensuring suitably trained staff are available to administer the
correct vaccines as required

• Vaccine storage
• Maintaining BVD antibody surveillance on a quarterly basis of

management groups prior to BVD vaccination

Figure 2. BVD check test results from 2014-2021

120% Vaccine started in Vaccine started
heifers pre breeding in milking herds

100%

80%

% antibody +ve60%
Number of positive tests/tags
Total number of tests (calves born)40%

20%

0%

Negative Positive Figure 3. BVD tag positive calves identified since 2016, in relation to total calves born

9.0 1800

Results 8.0 Vaccine started Vaccine 1600
7.0 in heifers pre started in 1400
Quarterly check test BVD antibody results went from 90%+ positive 6.0 heifers pre 1200
to 100% negative in 2 years using a combination of live BVD 5.0 breeding breeding 1000
vaccination and tag testing all calves (testing dams of positive calves 4.0 800
and culling all positives).

Tag and test positive calves stopped after 3 years from starting 3.0 600
heifer vaccination and 2 years after full herd vaccination, which
would have been quicker had PI identification in all replacement 2.0 400
animals been undertaken earlier.
1.0 200

0.0 0
Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3
2016 2016 2017 2017 2017 2017 2018 2018 2018 2018 2019 2019 2019 2019 2020 2020 2020 2020 2021 2021 2021

Number tag positive Total Tests

Conclusions

Planning a vaccine protocol in a large, multisite dairy herd to maximise compliance is critical. BVD vaccine protocols in all year round herds can

be effectively started as young as 6 months old as long as consideration is given to foetal protection in the first trimester and the planned start

of mating date.

Elimination of BVD can be achieved using a live BVD vaccine in the presence of PIs if a strict BVD tag and test policy is implemented on all calves

born (live and dead) and tracer bloods are done on the dams of all positive tag results and any positive animals culled promptly.

There was no horizontal transmission (creation of BVD PIs in non PI dams) of BVD when the herd was vaccinated with BVD live vaccine, even in

the presence of PIs. Check testing of BVD antibody in 6 month old heifers is possible and a useful surveillance tool in heifers born out of live BVD

vaccinated dams.

Reference: Meadows D. (2010) Cattle Practice 18(3): 202-215
Poster put together with the support of Boehringer Ingelheim Animal Health UK Ltd., makers of Bovela®. Bovela® lyophilisate and solvent for suspension for injection for cattle contains
modified live BVDV-1, non-cytopathic parent strain KE-9: 104.0–106.0 TCID50, Modified live BVDV-2, non-cytopathic parent strain NY-93: 104.0–106.0 TCID50. UK: POM-V. Further information
available in the SPC or from Boehringer Ingelheim Animal Health Ltd., Bracknell, Berkshire, RG12 8YS, UK. Tel: +44 (0)1344 746959 (sales & marketing enquiries) or +44 (0)1344 746957
(technical enquiries). Email: [email protected]. Bovela® is a registered trademark of Boehringer Ingelheim Vetmedica GmbH, used under licence. ©2021 Boehringer
Ingelheim Animal Health UK Ltd. All rights reserved. Date of preparation: Sep 2021. BOV-0164-2021. Use Medicines Responsibly (www.noah.co.uk/responsible)

2021 91

CATTLE PRACTICE VOLUME 29 PART 1

MSD ANIMAL HEALTH

Evaluation of Failure of Passive Transfer in neonatal dairy calves
in the Netherlands

1Pleun Penterman, 2Katharine Baxter-Smith, 1Ruben Tolboom, 1Geert Vertenten

1MSD Animal Health, Boxmeer, The Netherlands; 2MSD Animal Health, Milton Keynes, United Kingdom

OBJECTIVES CONCLUSION

The absorption of maternal immunoglobulins in the small intestine Depending on the used threshold 21 to 44 percent of neonatal
during the first 24 hours after birth, termed passive transfer, helps to calves in this study experience Failure of Passive Transfer. Although
protect the calf against common endemic disease organisms until its good progress has been made in the past years, there remains a
own immature immune system becomes fully trained and functional. considerable opportunity to improve the colostrum management
Colostrum management is the single most important management factor practices on Dutch dairy farms.
in determining calf health and survival. Although good progress has
been made in the past years, there remains a considerable opportunity KEYWORDS
for many dairy farmers. A recent US study reported Failure of Passive
Transfer (FPT) to affect 15.6% of calves tested, indicating a need for Failure of Passive Transfer, dairy calves, Netherlands, colostrum
continued efforts to improve colostrum management. The objective of
this study was to obtain prevalence data on FPT in dairy calves in The REFERENCES
Netherlands.
Furman-Fratczak K, Rzasa A, Stefaniak T. The influence of colostral immunoglobulin concentration in heifer calves’
MATERIAL AND METHODS serum on their health and growth. J Dairy Sci 2011;94:5536–43.
Gay CC. Failure of passive transfer of colostral immunoglobulins and neonatal disease in calves: a review. In Proc.
Neonatal dairy calves (n = 274) from several commercial farms in the 4th Int. Symp. Neonatal Dis. Veterinary Infectious Disease Organization, Saskatoon, SK, Canada. October 3–5,
Netherlands were enrolled in the study. Only calves aged between 2 and 1983. p. 346–62.
7 days were included in the trial. Godden SM, Lombard JE, Woolums AR. Colostrum management for dairy calves. Vet Clin Food Anim
2019;35:535-556.
Serum samples were tested at Royal GD Deventer (The Netherlands) Windeyer MC, Leslie KE, Godden SM, et al. Factors associated with morbidity, mortality, and growth of dairy
with a validated turbidimetric assay on a clinical chemical analyzer. heifer calves up to 3 months of age. Prev Vet Med 2014;113:231–40.

Different cut-off values for FPT and for evaluation of colostrum
management were used to analyse test results. A cut-off value for FPT
was defined as a serum gamma-globulin level lower than 10 g/L (Gay,
1983); a second cut-off value of 15g/L serum gamma-globulins was also
used based on studies by Furman-Fratczak and colleagues (2011) and
Windeyer and colleagues (2014) showing that dairy calves with serum
IgG levels greater than or equal to 15 g/L experienced lower rates of
respiratory disease. In addition, the revised individual and herd-based
evaluation standards by Godden and colleagues (2019) were used.

These include ranking in 4 categories: excellent (≥ 25.0 g/L), good
(18.0-24.9 g/L), fair (10.0-17.9 g/L), and poor (<10 g/L). These categories
can be applied to individual calves and to the operation for herd-based
evaluation based on the percentage of calves that should be represented
in each category.

RESULTS

The average as well as the median of the serum gamma-globulin level in
the sampled animals was 16 g/L ranging between 0 and 35 g/L. When
using a cut-off value of 10g/L, 21% of the animals experienced FPT,
while using a cut-off value of 15g/L would mean that 44% of the animals
experienced FPT.

When using the four categories defined by Godden and colleagues
(2019), 11% of the samples were excellent, 33% good, 35% fair and
21% poor. These results are worse than the proposed distribution
reflecting good colostrum management (>40% excellent, ~30% good,
~20% fair and <10% poor).

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2021 92