Comparison of Longhorn- and Red Poll-Sired Calves from ...

University of Nebraska - Lincoln

DigitalCommons@University of Nebraska - Lincoln

Roman L. Hruska U.S. Meat Animal Research U.S. Department of Agriculture: Agricultural
Center Research Service, Lincoln, Nebraska

2004

Comparison of Longhorn- and Red Poll-Sired
Calves from Crossbred Dams Calving at Two or
Three Years of Age

X H. Liu

University of Nebraska, Lincoln

A Perez Marquez

University of Nebraska, Lincoln

L. V. Cundiff

USDA, ARS, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE

L. D. Van Vleck

USDA, ARS, Roman L. Hruska U.S. Meat Animal Research Center, Lincoln, NE

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Liu, X H.; Perez Marquez, A; Cundiff, L. V.; and Van Vleck, L. D., "Comparison of Longhorn- and Red Poll-Sired Calves from
Crossbred Dams Calving at Two or Three Years of Age" (2004). Roman L. Hruska U.S. Meat Animal Research Center. Paper 163.
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The Professional Animal Scientist 20 (2004):330–335

Comparison of Longhorn- and Red
Poll-Sired Calves from Crossbred
Dams Calving at Two or Three
Years of Age1

X. H. LIU*,2, A. PEˆREZ MARQUEZ*, L. V. CUNDIFF†,3, PAS, and L. D. VAN VLECK‡
*Department of Animal Science, University of Nebraska, Lincoln 68583-0908; †USDA, ARS, Roman L.
Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933; and ‡USDA, ARS, Roman L.
Hruska U.S. Meat Animal Research Center, Lincoln, NE 68583-0908

Abstract able to sire breed were found only for consistent with this recommenda-
bone percentage of progeny of 3-yr-old tion, but birth weights and calving
Calving difficulty, survival from birth dams, but not for carcass weight, fat difficulty have been reported pre-
to weaning, birth weight, and weaning thickness, longissimus area, USDA qual- viously only for progeny of Longhorn
weight of 167 calves and carcass traits ity grades, and percentages retail product, and Red Poll sires produced by cows
of 88 cattle (63 for adjusted fat thick- fat trim, or bone. There was a signifi- calving at 4 yr of age or older in this
ness) were compared for progeny of Red cant interaction between sire breed and program, and this subset normally ex-
Poll and Longhorn bulls mated to cross- age of dam only for calving difficulty. periences less calving difficulty (Cun-
bred cows that calved at 2 or 3 yr of Within sire breed, calving difficulty of 2- diff et al., 1993). Gregory et al. (1978)
age. Results indicated that Longhorn- yr-old dams was greater than that for 3- reported that progeny of Red Poll,
sired calves required 28% less assistance yr-old dams, and calves from 2-yr-old Hereford, and Angus sires had signifi-
at calving than Red Poll-sired calves dams also were significantly lighter at cantly lighter birth weights, less calv-
when dams calved at 2 yr of age weaning than were calves from 3-yr-old ing difficulty, and greater survival to
(P<0.05), but there was no difference be- dams (P<0 .01). weaning than progeny of Maine An-
tween Red Poll- and Longhorn-sired jou, Chianina, and Gelbvieh sires.
calves for calving difficulty with 3- yr-old (Key Words: Calving Difficulty, Car- Cundiff et al. (1998) reported that
cows. Red Poll-sired calves had signifi- cass, Crossbreeding, Growth.) calving difficulty and birth weights
cantly greater birth and weaning BW were significantly less for progeny of
than did Longhorn-sired calves for 2-yr- Introduction Longhorn sires than for Hereford-An-
old dams. Significant differences attribut- gus reciprocal crosses, but survival
Longhorn and Red Poll bulls have was not significantly different. Thrift
1Published as Journal Series no.13795, Ne- the reputation of siring calves that et al. (1986) reported that progeny of
braska Agric. Res. Div., Univ. of Nebraska, are born with little dystocia. Thus, Longhorn sires were 5.9 kg lighter at
Lincoln 68583-0908. these sire breeds are often recom- birth and 26 kg lighter at weaning
2Current address: College of Animal Science mended for mating to heifers to re- than progeny of Red Poll bulls and
and Technology, Yunnan Agricultural Univer- duce incidence of calving difficulty, crossbred dams with various propor-
sity, Kunming City, Yunnan Province, Peo- but with the recognition that benefits tions of Angus, Brahman, Charolais,
ple’s Republic of China. of less calving difficulty may be par- and Hereford breeding calving at 2
3To whom correspondence should be ad- tially offset by unfavorable effects on and 3 yr of age. Calving difficulty
dressed: [email protected] growth to weaning and slaughter was not reported, but the calves were
ages. Previous results from the Germ- produced in a subtropical region (Lou-
plasm Evaluation (GPE) project at the isiana), where birth weights are
U.S. Meat Animal Research Center are known to be significantly lighter (8

Calves by Longhorn and Red Poll Sires 331

kg) and incidence of calving difficulty TABLE 1. Number of calves born and number slaughtered by sire
is less than that found in a temperate breeda, breed group of dam, and age of dam.
region (Nebraska) of the U.S. (Olson
et al., 1991). Koch et al. (1979) com- Item 2-yr-old dams 3-yr-old dams Total
pared carcass traits of steers for sev-
eral sire breeds including Red Poll but Sire of calf LT CTb LT CT LT CT
not Longhorn. The primary objective Red Poll
of the present study was to compare Longhorn 58 40 (15) 28 9 86 49
Longhorn- and Red Poll-sired prog- 37 21 (21) 44 18 81 39
eny from crossbred dams calving at 2 Dam of calf
or 3 yr of age for calving traits, ¹⁄₄ H ³⁄₄ A 7 4 (2) 62 13 6
weights at weaning and slaughter, ¹⁄₂ H ¹⁄₂ A 10 9 (4) 62 16 11
and carcass traits. ³⁄₄ H ¹⁄₄ A 13 8 (4) 64 19 12
¹⁄₄ P ³⁄₄ (A or H) 72
Materials and Methods ¹⁄₂ P ¹⁄₂ (A or H) 2 1 (1) 11 93
³⁄₄ P ¹⁄₄ (A or H) 3 2 (0) 10 43
Data for this study were from Cycle ¹⁄₄ B ³⁄₄ (A or H) 5 3 (3) 72 63
III of the GPE project at the U.S. ¹⁄₂ B ¹⁄₂ (A or H) 7 4 (3) 12 5 14 6
Meat Animal Research Center and ³⁄₄ B ¹⁄₄ (A or H) 15 10 (6) 72 27 15
specifically were from calves born in ¹⁄₄ S ³⁄₄ (A or H) 2 2 (2) 42 94
1985, 1986, 1987, 1988, and 1989 re- ¹⁄₂ S ¹⁄₂ (A or H) 8 6 (2) 40 12 8
sulting from multi-sire clean-up mat- ³⁄₄ S ¹⁄₄ (A or H) 12 8 (2) 64 16 8
ings to Red Poll and Longhorn bulls. ¹⁄₄ B ¹⁄₄ S ¹⁄₄ H ¹⁄₄ A 7 3 (2) 51 13 7
A total of 8 Red Poll and 11 Long- 4 3 (3) 94
horn bulls were used. The Red Poll
bulls were sampled from a broad- aH = Hereford, A = Angus, P = Pinzgauer, B = Brahman, and S = Sahiwal.
based purebred herd maintained as bLT = number of calves born; CT = number of animals for carcass traits. Number of
part of the Germplasm Utilization observations for adjusted fat thickness are shown in parentheses. Adjusted fat
Project at the U.S. U.S. Meat Animal thickness was not recorded for steers and heifers produced by 2-yr-old dams in the
Research Center (Gregory et al., first year of the experiment (i.e., 1985).
1991). The Longhorn bulls were sam-
pled from the herd of purebred Long- were weaned in September at an aver- tended period of 170 d containing
horn cattle maintained at the Fort Ni- age age of 127 d. Following weaning, about 2.24 Mcal ME/kg DM and
obrara National Wildlife Refuge (Val- steers and heifers produced in 1985, 12.34% CP consisting of 54% corn si-
entine, NE). Two or more bulls of 1987, and 1988 were placed in sepa- lage, 42% alfalfa haylage, and 4.0%
each sire breed, Red Poll or Long- rate pens by sex. They were allowed supplement. Then, over an 8-wk pe-
horn, were run together in separate to adjust to the dry lot for a 6- to 8- riod, they were gradually shifted to
pastures during the 21-d natural ser- wk period during which time they daily feeding of a higher concentrate
vice clean-up mating period each were fed a mixture of grass and al- finishing diet containing about 3.04
year. The cows were F2 and reciprocal falfa hay free choice and introduced Mcal ME/kg DM and 10.9% CP con-
backcrosses born in 1983 through to a mixed diet with approximately sisting of 70% corn, 25% corn silage,
1986 out of F1 cross dams that had 2.63 mcal ME/kg DM and 13.2% CP and 5% supplement. Steers and heif-
been produced in 1975 and 1976 consisting of 43% corn silage, 31% ers were slaughtered serially at two or
from original matings of Hereford, corn, 19% alfalfa hay, and 8% supple- three slaughter dates spanning 33 to
Angus, Pinzgauer, Brahman, and Sahi- ment. In 1985, steers and heifers 52 d in each year. Steers were slaugh-
wal bulls to Hereford and Angus were fed daily a mixed diet con- tered at an average age of 454 d, and
cows. The F2 and reciprocal backcross taining about 2.72 Mcal ME/kg DM heifers were slaughtered at an average
cows calved as 2-yr olds in 1985 and 12.88% CP consisting of 56% age of 443 d of age in a commercial
through 1988 and as 3-yr olds in corn silage, 33% corn, and 11% sup- abattoir. After a 24-h chill, compo-
1986 through 1989. The number of plement for a 45-d growing period. nents of USDA yield grade (adjusted
calves produced by each sire breed, Then over 2 mo, they were gradually fat thickness; longissimus area; esti-
breed group of dam, and age of dam shifted to a finishing diet containing mated kidney, pelvic, and heart fat
are shown in Table 1. 3.12 Mcal ME/kg DM and 10.4% CP percentage; and carcass weight) and
consisting of 83% corn, 13% corn si- USDA quality grade (marbling, matu-
Calves were born from early April lage, and 4% supplement. In 1987 rity) were obtained.
to late May. Male calves were cas- and 1988, the steers and heifers were
trated within 24 h of birth. Calves fed a growing diet daily for an ex- Carcass data were from calves born
in 1985, 1987, and 1988. Retail prod-

332 Liu et al.

TABLE 2. Conversion chart for marbling scores. gosity in the dams expected from Bos
taurus × Bos taurus, Bos taurus × Bos in-
Item Numerical marbling scorea dicus, and Bos indicus × Bos indicus
crosses. Fixed effects and covariates
Practically devoid 200 for carcass traits were the same as for
Traces 300 live traits, except only sex at weaning
Slight 400 was used. Age (d) at weaning and
Small 500 slaughter were additional covariates.
Modest 600 No random factors were included, as
Moderate 700 individual sires were unknown and
Slight abundant 800 each dam had only one calf. Analyses
Moderately abundant 900 were conducted with the MTDFREML
programs modified for a fixed effects
aA small marbling score (e.g., 20) was converted to a numerical score of 500 + model (Boldman et al., 1995). Tests
20 = 520. of sire breed using the residual error
term rather than the more appro-
uct, fat trim, and bone yields were es- Calving difficulty was measured on priate term of sire within breed (un-
timated using the following equa- a categorical scale (1 = no difficulty, feasible because individual sires could
tions (Shackelford et al., 1995): 2 = little difficulty by hand, 3 = little not be identified with the use of mul-
difficulty with calf jack, 4 = slight dif- tiple sires per pasture) were biased.
Percentage of totally trimmed re- ficulty with calf jack, 5 = moderate Given that many of the traits studied
tail product yield = 74.9 − difficulty with calf jack, 6 = major dif- have a moderate to high heritability,
5.8402 (adjusted fat thickness, ficulty with calf jack, 7 = caesarean the mean square for sire within
cm) − 0.0205 (marbling score) + birth, and 8 = abnormal presentation) breed, if estimable, would be larger
0.1018 (longissimus area, cm2) − according to BIF Guidelines (1996). than the residual mean square. This
1.0384 (estimated percentage of Calving difficulty was analyzed as a concern prompted the use of previ-
kidney, pelvic, and heart fat); binomial trait as described in Table 3. ous estimates of heritability from re-
Unadjusted means and standard devi- ports involving the same traits on ani-
Percentage of fat trim yield (to- ations for preweaning, postweaning, mals produced in the GPE Program at
tally trimmed) = 5.1 + 7.5795 and carcass traits are shown in Table the U.S. Meat Animal Research Cen-
(adjusted fat thickness, cm) + 4. ter (Koch et al., 1982; Wheeler et al.,
0.0230 (marbling score) + 2001) to partition the residual mean
1.3632 (estimated percentage of A fixed effects model was used to square (expected value ∼ σw2 + k1 σs2,
kidney, pelvic, and heart fat) – analyze the data. For traits measured where k1 ∼ 0.523 for preweaning
0.0825(longissimus area, cm2); on the live animal, fixed effects in- traits and 0.632 for postweaning
and cluded year of birth, sex at birth or traits) into residual (σw2 ) and sire (σs2)
weaning (steers, heifers), calf sire components of variance. The ex-
Percentage of bone yield = 17.5 breed, and age of dam. Covariates pected mean squares for sire within
− 1.7581 (adjusted fat thickness, were calendar birth day and fractions breed of sire (expected value ∼ σw2 +
cm) − 0.3855 (estimated kidney, of inheritance from Hereford, Angus, k2 σ2w, where k2∼ 8.78 for preweaning
pelvic, and heart fat per- Pinzgauer, Brahman, and Sahiwal traits and 6.76 for postweaning traits)
centage). dams and also fractions of heterozy- with 9 df for preweaning traits and 7

Weaning weight was adjusted for TABLE 3. Conversion of traits to binomial scale.
age of calf (205 d) according to Beef
Improvement Federation (BIF) Guide- Item Categorical scores Binomial scale
lines (1996). Calf survival was on a bi- Calving difficulty
nomial scale (0 = died before and 1 = 1 and 2 0
alive at weaning time). Marbling USDA Choice 3 to 7 1
score was on a modified categorical USDA Standard Not used
basis as described in BIF Guidelines 8
(1996) and as shown in Table 2. 0
USDA Choice and Standard quality Marbling score <500 1
grade were analyzed as binomial Marbling score ≥500
traits (Table 3). 0
Marbling score >399 1
Marbling score ≤399

Calves by Longhorn and Red Poll Sires 333

TABLE 4. Unadjusted means and standard deviations (SD). than did Longhorn-sired calves
(P<0.05) and tended to have greater
Item Mean SD (P<0.10) birth and weaning BW.
These results were similar to those
Calving difficulty, % 10 3 from previous research for calving dif-
Survival birth to weaning, % 98 15 ficulty, birth BW, and weaning BW
Birth BW, kg 31.68 in the GPE Program at the U.S. Meat
Weaning BW, kg 180.66 5.42 Animal Research Center (Cundiff et
Live slaughter BW, kg 429.87 31.46 al., 1993) and consistent in direction
Hot carcass wt., kg 259.94 56.93 but only about one-half as great in
Marbling, score 494.21 38.05 magnitude as those reported for
Fat thickness, cm 96.69 weights at birth and weaning in Loui-
Adjusted fat thickness, cm 0.99 siana (Thrift et al., 1986).
Longissimus area, cm2 0.72 0.53
Kidney, pelvic, and heart fat, % 67.35 0.36 Red Poll- and Longhorn-sired calves
USDA Choice grade, % 3.01 7.55 did not differ significantly in carcass
USDA Standard grade, % 43 0.71 traits (Table 6); however, Red Poll-
Retail product, % 16 50 sired cattle tended to have a lower
Fat trim, % 64.70 37 percentage of bone (P<0.10). No sig-
Bone, % 20.10 3.56 nificant differences caused by sire
15.19 4.58 breed were found for calf survival; fi-
0.68 nal weight; carcass weight; marbling
score; fat thickness; longissimus area;
df for postweaning traits were then in Table 6 for postweaning traits mea- kidney, pelvic, and heart fat percent-
used to compute standard errors and sured before slaughter and for carcass age; retail product percentage; fat
approximate t tests for sire breed of traits. trim percentage; the percentage of car-
calves, sire breed of calves with 2-yr- casses grading USDA Choice or
old dams, sire breed of calves with 3- Comparison of Ages of Dam. Calv- greater; or the percentage of carcasses
yr-old dams, and sire breed × age of ing difficulty for 2-yr-old dams was grading USDA Standard.
dam interaction (each with 1 df). significantly greater than that for 3-
yr-old dams. The calves of 2-yr-old Comparison of Calves of Red Poll
Results and Discussion dams also were significantly lighter and Longhorn Sires by Age of Dam.
than calves of 3-yr-old dams for wean- Because age of dam may have an in-
Estimates of linear contrasts and ing weight. No significant differences fluence on effect of sire breed, the in-
standard errors between sire breeds, caused by age of dam were found for teraction between sire breed and age
ages of dams, and the interaction of other traits. of dam was also tested for each trait.
sire breed and age of dam are shown Results in Table 5 indicate that calv-
in Table 5 for preweaning traits and Comparison of Sire Breeds Across ing difficulty of Red Poll-sired calves
Both Ages of Dam. Results in Table was greater (P<0.05) than that of
5 indicate that Red Poll-sired calves Longhorn-sired calves when dams
had greater calving difficulty (P<0.05)

TABLE 5. Estimates of linear contrasts (d) and standard errors (SE) for traits measured before slaughter
between Red Poll and Longhorn (RP - LH) sire breeds, between ages of dam, and interaction of sire breed and
age of dam.

RP - LH RP - LH RP - LH Sire breed 2-yr-old −
all ages of dams with 2-yr dams with 3-yr dams × age of dam 3-yr-old dams

Item d SE d SE d SE d SE d SE

Calving difficulty, % 14* 6 28* 8 0 7 29* 11 16* 5
Survival to weaning, % 3 3 4 −3
Birth BW, kg 0 115 3.43* 1.69 4 67 43
Weaning BW, kg 2.27† 4.95 9.02 1.10
12.06† 20.82* 3.29 1.56 2.33 2.77 −0.75 0.92

8.35 17.53 12.33 −20.07* 5.34

*P<0.05.
†P<0.10.

334 Liu et al.

TABLE 6. Estimates of contrasts (d) and standard errors (SE) for carcass traits between Red Poll and Longhorn
(RP - LH) breeds of sire, between ages of dam, and interaction of sire breed and age of dam (age end point,
448 d).

RP - LH RP - LH RP - LH Sire breed 2-yr-old −
all ages of dams with 2-yr dams with 3-yr dams × age of dam 3-yr-old dams

Item d SE d SE d SE d SE d SE

Final BW, kg 29.83 18.07 55.62† 25.00 4.04 27.54 51.58 38.15 −19.09 13.96
Hot carcass weight, kg 18.96 11.22 27.11 15.19 10.82 17.22 16.29 23.44 −13.06 8.71
Marbling score 23.44 33.17 44.85 38.96 50.82 −31.04 69.18
Fat thickness , cm 7.91 −0.03 34.94 23.48
Adjusted fat thickness , cm 0.28 0.17 0.27 0.23 0.29 0.26 0.35 −0.20 0.12
Longissimus area, cm2 0.26† 0.11 0.22 0.16 0.30 0.17 0.07 0.13 −0.10 0.08
Kidney, pelvic, and heart fat, % 0.78 0.88 −0.13 3.00 1.68 3.42 −1.81 4.68 1.71
USDA Choice, % −0.24 0.22 −0.49 0.29 0.01 0.33 −0.50 0.45 1.22 0.17
USDA Standard, % 9 19 4 25 14 27 −11 39 −0.16
Retail product, % −6 12 1 17 −14 19 16 26 −1 14
Fat trim, % −1.59 1.13 −0.77 1.56 −2.41 1.73 1.41 −10 10
Bone, % 1.92 1.40 1.28 1.93 2.56 2.13 0.55 1.75
−0.40† 0.20 −0.28 0.27 −0.53 0.30 −0.16 0.24 0.26 0.85
−0.17 −0.48 1.07
0.16
0.30

*P<0.05.
†P<0.01.

were 2 yr old. No difference caused program (Wheeler et al., 1997; Cun- ple of Hereford and Angus bulls born
by sire breed for calving difficulty was diff et al., 1998) when dams were in the mid1980s (Cundiff et al.,
found for 3-yr-old dams. The calves calving at 4 yr of age or older. Here- 1993). Previously, post-weaning aver-
of 2-yr-old dams by Red Poll sires ford-Angus reciprocal crosses pro- age daily gains and slaughter weights
were significantly heavier (Table 5; duced from matings to reference sires adjusted for age were less (P<0.05) for
P<0.05) at birth and weaning than (10 Hereford, and 14 Angus bulls progeny of Longhorn sires than for
were calves of Longhorn sires, and fi- born in the late 1960s) provided ties progeny of Red Poll sires when de-
nal weight of cattle slaughtered for analyses pooled over the first four rived from analyses pooled over Cy-
tended to be heavier (Table 6; cycles of the GPE Program (Cundiff cles II and IV of the GPE Program
P<0.10). However, for calves from 3- et al., 1993). Results from this report (Cundiff et al., 1993). In addition, car-
yr-old dams, differences caused by indicated that Longhorn and Red Poll casses from progeny of Longhorn
sire breed were not significant for were comparable in calving ease in sires had significantly greater percent-
birth, weaning, and slaughter cows calving at 4 yr of age or older. ages of retail product than progeny of
weights. Calves by Red Poll and Long- That result is consistent with the pres- Red Poll sires, which were compara-
horn sires mated to dams to calve as ent study for dams calving at 3 yr of ble with Hereford-Angus cross prog-
2-yr olds or as 3-yr olds were not sig- age. However, the present study indi- eny by reference sires born in the
nificantly different for survival at cates Longhorns have a significant ad- 1960s or more recently sampled sires
weaning or any of the carcass traits vantage in calving ease over Red Poll born in the mid 1980s (Cundiff et al.,
studied. Only for calving difficulty sires for dams calving at 2 yr of age. 1993). Although fat trim percentages
was there a significant interaction be- Results from the present and previous of Red Poll-sired progeny were compa-
tween sire breed and age of dam. studies have indicated that progeny rable with those of Hereford-Angus
of Longhorn sires were significantly crosses in Cycle II, progeny by Red
Results from this experiment are lighter at birth and weaning than Poll sires had significantly greater per-
consistent with previous reports from were progeny of Red Poll sires that centages of kidney, pelvic, and heart
the GPE Program at the U.S. Meat An- were comparable with Hereford-An- fat but significantly less subcutaneous
imal Research Center in which prog- gus crosses by reference sires born in fat thickness than Hereford-Angus
eny of Red Poll sires were compared the 1960s (reference sires were Here- cross progeny by reference sires born
with progeny of six other sire breeds ford and Angus bulls born in the late in the 1960s or more recently sam-
in Cycle II (Gregory et al., 1991) and 1960s used in Cycles I, II, III, and IV) pled sires born in the mid 1980s. Re-
in which progeny of Longhorn sires but lighter than Hereford-Angus cross sults from the previous studies indi-
were compared with progeny of 10 progeny sired by a more recent sam- cate that progeny by Longhorn sires
other sire breeds in Cycle IV of the

Calves by Longhorn and Red Poll Sires 335

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Longhorn-sired progeny than in Red pected for progeny of Red Poll sires. terization of biological types of cattle—Cycle
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