July 25th – 27th, 2023 KENYIR NATURAL RESEARCH STATION (SPAK), UMT RM 1,500 / Person WORKSHOP ON for Parasites Detection in Fish CANDLING METHOD on a Boathouse
TENTATIVE “ WORKSHOP ON CANDLING METHOD ” July 25 – 27, 2023 (Tuesday – Thursday) DAY TIME ACTIVITY VENUE First Day 08.00 am – 09.00 am Registration and Gather AKUATROP Lobby 09.00 am – 10.30 am Depart to SPAK, Tasik Kenyir from UMT by Bus Breakfast UMT Bus 10.30 am – 11.30 am Program and Safety Briefing SPAK Auditorium, UMT 11.30 am – 12.30 pm Check In SPAK Hostel, UMT 12.30 pm – 02.00 pm Lunch and A Break SPAK Cafetaria, UMT 02.00 pm - 03.00 pm THEORY 1 Introduction to Zoonotic Fish and Shellfish Parasites AP Dr. Muhammad Hafiz Borkhanuddin SPAK Auditorium, UMT 03.00 pm – 04.00 pm THEORY 2 Fish Anatomy & Quality Assessment Dr. Sairatul Dahlianis Ishak SPAK Auditorium, UMT 04.00 pm – 04.30 pm Tea Break SPAK Cafetaria, UMT 04.30 pm – 05.30 pm THEORY 3 Seafood Freshness Index AP Dr. Nurul Ulfah Karim SPAK Auditorium, UMT 05.30 pm – 07.00 pm Leisure Time / Fishing / Houseboat Cruising (Siti Maya) UMT Houseboat 07.00 pm – 08.30 pm Dinner and Rest SPAK Cafetaria, UMT 08.30 pm – 10.30 pm THEORY 4 Candling Method Theory Mdm Norazizah Kemat (DoF) SPAK Auditorium, UMT 10.30.00 pm – 11.30 pm Supper SPAK Cafetaria, UMT Second Day 07.30 am – 08.30 am Breakfast / Check Out from SPAK,UMT SPAK Cafetaria, UMT 08.30 am – 10.30 am Houseboat Cruising to Lasir Waterfall Private & UMT Houseboat 10.30 am – 11.00 am Tea Break Houseboat 11.00 am – 01.00 pm PRACTICAL 1 Fish and Shellfish Parasitology Houseboat 01.00 pm – 02.30 pm Lunch and A Break Houseboat 02.30 pm – 04.30 pm PRACTICAL 2 Seafood Freshness Index & Candling Method for Parasite Detections in Fish and Shellfish (Finfish, Shrimp, Crab) Houseboat 04.30 pm – 05.00 pm Tea Break Houseboat 05.00 pm – 07.00 pm Leisure Time (Waterfall Bathing / Fishing) Lasir Waterfall 07.00 pm – 08.00 pm Dinner and Rest Houseboat 08.00 pm – 10.00 pm PRACTICAL 3 Candling Method for Parasite Detections in Fish and Shellfish (Squid, Cuttlefish, Octopus dan Bivavlve) Houseboat 10.00 pm – 10.30 pm Presentation of Certificates and Closing Ceremony Houseboat 10.30 pm – 12.00 am Supper / Leisure Time / Karaoke / Fishing Houseboat Third Day 07.00 am – 08.00 am Breakfast Houseboat 08.00 am – 10.30 am Houseboat departs to Kelah Sanctuary Houseboat 10.30 am – 12.00 pm Jungle Tracking to Lubuk Kelah and Fish Feeding Activities Kelah Sanctuary 12.00 pm – 12.40 pm Jungle Tracking Back to The Boat House Kelah Sanctuary 12.40 pm – 01.40 pm Lunch Cruise on Houseboat Taman Herba 01.40 pm – 02.30 pm Visiting Taman Herba Taman Herba 02.30 pm – 03.30 pm Depart Back to Gawi Jetty Houseboat 03.30 pm – 04.00 pm Shopping at Duty Free Shops Gawi Jetty 04.00 pm – 05.00 pm Return Back to UMT by Bus Gawi Jetty 05.00 pm – 05.30 pm Dismiss AKUATROP Lobby
CONTENTS TENTATIVE PORGRAM LECTURE NOTES 1. Exploring Zoonotic Parasitology: Fish-borne Parasitic Zoonoses 2. Fish Anatomy & Quality Assessment 3. Seafood Freshness Index 4. Candling Method For Food Borne Parasites Detection PRACTICAL SHEET 1. Practical 1: Drawing Sheet 2. Practical 2: Borang Pemeriksaan Indeks Kesegaran Ikan 3. Practical 3 : i. Data Sheet - Purposed of Analysis: Detection of Parasites – Animal Health ii. Data Sheet - Detection Parasites of Fish that Risk to Public Health (Endoparasite Examination)
LECTURE NOTES 1
23/07/2023 1 Exploring Zoonotic Parasitology: Fish-borne Parasitic Zoonoses Zoonotic parasitology is a crucial field of study with parasites transferring between animals and humans. Fish-borne diseases occur due to the increasing popularity of eating raw fish or fish products. This presentation will outline the importance of understanding zoonotic parasites to prevent, control, and treat these diseases. HB by Hafiz Borkhanuddin
23/07/2023 2 Disease & Parasitology • The term “disease” conveys adverse impacts, and “disease” implies that parasites cause disorder (eg aquatic environment) • Disease refers to any condition that impairs the normal functioning of the body. Pathology is the study of disease. • Although we don’t know their exact contribution to biodiversity, when researchers have included them, parasites increase insight into taxonomic and functional diversity in marine systems. • Parasites affect food webs • Bringing unique consumer strategies (e.g., parasitoidism, parasitic castration) to food webs. • Parasites also balance how consumer–resource body size ratios Foundations of Parasitology Fish have a high diversity of parasites, with three to four parasite species found in a single fish specimen. Proper research and identification of parasites in fishery products are essential to improve the safety and nutrition of the human diet.
23/07/2023 3 Foundations of Parasitology • Fish and fishery products offer a valuable and inexpensive source of high-quality animal protein • > 80,000,000 tonnes marine fish landed & processed for humans. • ~20% of total animal protein intake for 3 billion people • ^ human diet more research into harmful organisms of fishery products Parasitism/Parasites Parasitism is the most successful form of life on earth, with more parasitic than free-living species having been described During evolution, parasitism has independently developed within the most diverse groups of organisms - studies show that every organism has been parasitized, at least temporarily, within its life span
23/07/2023 4 • Nutrients for the parasite • Offers protection • survival of various developmental stages of the parasite/reproduction What kind of benefits that parasites gained from their hosts? • Mechanical damage through their histophagous or haematophagous diet • Removal of important nutrients from the host (food competitors) • Parasite (‘excretions’) can lead to intoxication of the host • Secondary infections - parasites aid pathogenic microorganisms (e.g. viruses, bacteria, fungi) to enter the host What does the parasites
23/07/2023 5 Parasite life stages/cycles •Monoxenous (one-host) •Heteroxenous (multiple-host) Parasite-host specificity •Strict/obligate (stenoxenous) •Loose (euryxenous)
23/07/2023 6 Which one is Monoxenous and Heteroxenous? Monoxenous Heteroxenous
23/07/2023 7 Zoonotic Parasitology Zoonotic parasitology is a branch of parasitology that focuses on the study of parasites that can be transmitted between animals and humans. These parasites, known as zoonotic parasites, have the ability to infect and cause diseases in both animals and humans. They can be protozoa (singlecelled organisms), helminths (worms), or arthropods (insects or arachnids) that act as vectors for the parasites. Zoonotic parasitology - understand the transmission, lifecycle, epidemiology, and impact of these parasites on human and animal health, as well as develop strategies for their prevention, control, and treatment. Overview of Zoonotic Parasitology Protozoan Parasites Parasitic Cryptosporidium and Giardia can contaminate water and infect aquatic life. Helminthic Parasites Anisakid nematodes can be found in marine fish while certain tapeworms can infect freshwater fish. Arthropod-borne Parasites Mosquitoes and ticks can transmit diseases to humans. Diagnosis can be by blood tests or microscopic examination after disease onset.
23/07/2023 8 Cryptosporidium and Giardiasis Anisakiasis and Diphyllobothriasis Mosquito-borne Diseases Zoonotic Parasite Emergence 1 Encroachment into Wildlife Habitats Zoonotic parasites often have natural reservoirs in wildlife populations. Environmental changes leads to blending of habitats and increased risks of cross-species transmission of zoonotic parasites. 2 Human Activities Human activities can increase the risk of contact with zoonotic parasites by bringing humans closer to wild animals and their parasites. 3 Global Travel and Trade International movement of animals and global trade in food products can introduce new zoonotic parasites to new regions.
23/07/2023 9 Zoonotic Parasite Emergence 4 Improper Handling Improper handling, processing, and consumption of food can expose humans to zoonotic parasites present in the food chain. 5 Environmental Changes Environmental changes due to climate change can influence the distribution and prevalence of both parasites and their hosts. Increases in temperature, humidity, and rainfall may lead to ecological changes and parasite emergence. Zoonotic Parasite Emergence 6 Antimicrobial Agents The overuse and misuse of antimicrobial agents can lead to the development of drug-resistant parasites. 7 Susceptibility of Individuals People with weakened immune systems are more susceptible to zoonotic parasite infections. 8 Mutations and Adaptations Zoonotic parasites can undergo genetic mutations or adaptations that enhance their ability to infect and transmit between hosts. 9 Agricultural Practices and Food Safety Foodborne or waterborne parasites can emerge due to agricultural practices and poor food production, handling and storage practices.
23/07/2023 10 Fish-borne Zoonotic Diseases Fish can be hosts for a variety of parasites and pathogens that can cause human infections through different routes. Preventing fish-borne zoonotic diseases involves adopting good food safety practices, proper cooking techniques, and implementing strict regulations and monitoring of fish production and handling. Raising awareness among communities about risks and preventive measures is essential in reducing the burden of these infections. Consuming Raw Fish Consuming raw or inadequately cooked fish that harbor infectious parasites can lead to zoonotic infections. Reservoir Hosts Fish can act as reservoir hosts for certain zoonotic parasites, and the water in which they live can become contaminated with infectious stages of these parasites. Direct Contact with Infected Fish Direct contact with infected fish or their internal organs can also pose a risk of infection. Cross-contamination Poor food handling practices can lead to crosscontamination of other food items with fish-borne pathogens. Raw or Partially Cooked Dishes Some traditional dishes involve the use of raw or partially cooked fish. Fishmeal and Fish-based Products The use of fishmeal or fish-based products in animal feed, pet food, or aquaculture can introduce fish-borne pathogens into the food chain. Aquaculture Management Poor management practices in aquaculture systems can lead to the proliferation of infectious agents in fish populations. International Trade International trade in fish and fish products can facilitate the movement of fish-borne parasites to different regions, introducing new zoonotic risks.
23/07/2023 11 F I S H-B O R N E D I S E A S E S R E L AT E D TO D I G E N E A , C E S TO D A & N E M ATO D A Among the most common diseases associated with fish consumption are: • opisthorchiasis • intestinal trematodiasis • diphyllobothriasis • anisakidosis The main parasite groups involved are • digenean trematodes (families Heterophyidae, Opisthorchiidae &Nanophyetidae) • cestodes (genus Diphyllobothrium) • anisakid nematodes (Anisakis simplex (s.s.), A. pegreffii, Pseudoterranova decipiens) • Most of these parasites can be ingested through the consumption of freshwater fish: ⚬ digenean trematode ⚬ freshwater fish as intermediate hosts • Fishery products (marine habitat), ⚬ anisakid nematodes ⚬ fish-borne zoonoses • Cestodes are distributed in both marine and freshwater habitats worldwide. ⚬ Diphyllobothrium are found in freshwater fish ⚬ Marine examples ￭ Diphyllobothrium cameroni ￭ D. cordatum ￭ D. hians ⚬ Diphyllobothriasis ￭ often asymptomatic ￭ can cause abdominal and digestive discomforts ￭ (rare) vitamin B12 intake by the tapeworm can ￭ lead to megaloblastic anaemia ￭ (Dibothriocephalus latus infections)
23/07/2023 12 23 NEMATODES > 250 known families, ~ 40,000 sp, roundworms are one of the most species –rich and diverse taxa within the Metazoa Colonised every habitat and ecosystem on earth, predominantly free-living and feeding on decomposing organic matter 24 NEMATODES Only ~4% of known genera are parasitic to freshwater and marine fishes
23/07/2023 13 Nematodes • Achieve their temporal and spatial dispersal • Use of paratenic hosts • Low host specificity • Free-living stages that actively search for susceptible hosts • Infection of short-lived organisms (e.g. small invertebrates) that occur in vast numbers • Increase likelihood of encountering successive host in a diluted environment, • contact between successive hosts may be periodic or even rare • Sites of infection: Haemocoel (crustacean hosts), body cavity (and mesenteries), surfaces of internal organs and muscles are common. 28 General Nematode Life Cycle Adults live within the intestine of their definitive hosts (Cetacea, Pinnipedia, piscivore birds, piscivore fish). After copulation, females produce eggs which are excreted by the host. Eggs mature in the water column from L1 to L2 larvae. L2 larvae hatch in the water column. L2 larvae become ingested by small crustaceans (Cyclopoida, Amphipoda, Euphausiacea). Within the crustaceans, they develop into infective L3 larvae. The infected crustaceans are rarely eaten directly by the final host andmostly ingested by a paratenic host
23/07/2023 14 29 General Nematode Life Cycle (f) ingested by a paratenic host (small fish, Cephalopoda), where they penetrate the intestine wall and encapsulate on organs. (g) these paratenic hosts are either eaten by further paratenic hosts (predatory fish), where they encapsulate on organs again or by (h) accidental hosts like humans or the final hosts Anisakiasis How Anisakiasis is Contracted Anisakiasis is caused by consuming raw or undercooked fish or seafood that is infected with the larvae of a type of roundworm called Anisakis. The larvae can cause severe inflammation of the stomach and intestines, leading to symptoms such as stomach pain, nausea, vomiting, and sometimes allergic reactions. Symptoms of Anisakiasis The symptoms of anisakiasis can appear within hours or days of eating infected seafood. They can include severe stomach pain, nausea, vomiting, and sometimes allergic reactions such as hives, itching, and swelling. Preventing Anisakiasis To prevent anisakiasis, it's important to cook seafood at temperatures above 60 C (140 F) or freeze it at temperatures below -20 C (-4 F) for a specific duration to kill the larvae. It's also important to avoid consuming raw or undercooked seafood, especially if you are pregnant, elderly, or have a weakened immune system.
23/07/2023 15 • The occurrence of certain nematodes (e.g. Anisakidae: Pseudoterranova, Anisakis) in the musculature or internal organs of their intermediate or paratenic hosts is well documented and has been extensively investigated in a variety of fish, especially those with high commercial value. • This is not only related to their significance as pathogens and potential triggers of zoonotic diseases but also to the economic aspects resulting from the spoilage of infected fish products. Fish (freshwater/marine): – Mackerel – Rockfish – Salmon – Squid – Herring Effect on human – Worm infection – Allergic
23/07/2023 16 Anisakiasis: Adverse Effects Anisakiasis can lead to a range of adverse effects on human health. In this section, we explore the potential symptoms that can be seen in severe cases of anisakiasis. 1 Gastrointestinal symptoms Abdominal pain, nausea, vomiting, and diarrhea are common symptoms of anisakiasis. 2 Allergic reactions In some cases, an allergic reaction can occur, leading to hives, itching, swelling, and difficulty breathing. 3 Bowel obstruction A large number of larvae or the formation of granulomas can cause rare instances of bowel obstruction, leading to severe pain and discomfort. 4 Perforation of the gastrointestinal tract In some severe cases, the larvae can cause perforation of the stomach or intestines, leading to a medical emergency requiring immediate surgical intervention. 5 Anaphylaxis Severe allergic reactions occur very rarely, leading to anaphylaxis, a life-threatening allergic reaction. 6 Mental health impact Experiencing severe symptoms and uncertainty about the cause of illness can lead to anxiety, stress, and psychological distress.
23/07/2023 17 Capillariasis How it's Contracted Capillariasis is caused by consuming raw or undercooked animal products that are infected with a type of nematode worm known as Capillaria. Symptoms The most common symptoms include abdominal pain, diarrhea, and weight loss. In severe cases, the infection can cause liver or lung damage. Prevention To prevent capillariasis, practice good hygiene, including proper handwashing before handling food, consuming only properly cooked food, and avoiding raw or undercooked animal products, especially liver. Angiostrongyliasis 1 How it's Contracted Angiostrongyliasis, or rat lungworm disease, is contracted by consuming raw or undercooked intermediate hosts, such as snails, slugs, and prawns, infected with the roundworm Angiostrongylus cantonensis. 2 Symptoms The most common symptoms include severe headaches, neck stiffness, nausea, vomiting, and fever. In more severe cases, the infection can lead to sensory disturbances, paralysis, or meningitis. 3 Prevention To prevent angiostrongyliasis, it's important to properly handle and cook food, including thoroughly washing fresh produce and properly cooking intermediate hosts.
23/07/2023 18 Gnathostomiasis 1 How it's Contracted Gnathostomiasis is a parasitic infection caused by the larvae of the roundworm Gnathostoma spinigerum or Gnathostoma hispidum. It can be contracted by consuming raw or undercooked freshwater fish or eels that are infected with the larvae. 2 Symptoms The symptoms of gnathostomiasis can vary depending on the severity of the infection and the location of the larvae within the body. Common symptoms include abdominal pain, vomiting, and fever. 3 Prevention To prevent gnathostomiasis, it's important to thoroughly cook all freshwater fish or eels before consuming them.
23/07/2023 19 Myammar, Malaysia & Thailand L3 G. malaysiae in intermediate host: Freshwater eel (Fluta alba) Freshwater prawn ID: 400µm, 20-26 cell Geographic distribution Gnathostoma malaysiae is primarily found in Southeast Asia, particularly in countries like Malaysia, Thailand, and parts of Indonesia. The parasite's distribution is closely associated with its intermediate hosts, which are freshwater fish and crustaceans. Life cycle The life cycle of Gnathostoma malaysiae is complex and involves several hosts. The adult worms typically reside in the stomach or intestines of definitive hosts, such as cats, dogs, and other carnivores. These animals shed eggs into the environment through their feces Intermediate hosts Freshwater fish and crustaceans serve as intermediate hosts for Gnathostoma malaysiae. The eggs containing infective larvae are ingested by these intermediate hosts.. Clinical manifestations Condition known as gnathostomiasis. Symptoms vary depending on the site of larval migration but commonly include migratory swellings under the skin, often referred to as "larva migrans." The larvae can also migrate to the eyes, brain, lungs, and other organs, causing serious and potentially life-threatening complications. Diagnosis Diagnosing Gnathostoma malaysiae infection in humans can be challenging due to the diverse clinical presentations and the need for specific laboratory tests, such as serological assays and identification of larvae in biopsy or surgical specimens. Treatment Treatment for gnathostomiasis typically involves the use of anthelmintic drugs to kill the parasites. The timing of treatment is crucial to prevent further complications associated with larval migration. Gnathostoma malaysiae
23/07/2023 20 Cestodes • Exclusively endoparasitic. • They infect many teleost and bony fish species but usually do not appear to cause much harm to their vertebrate definitive hosts. • Adults inhabit the digestive tract or occasionally its associated organs. • Once anchored to the host’s intestinal wall, cestodes absorb nutrients and remain stationary for the rest of their life span. 45 Morphology • 3 distinct body regions: • Scolex • distinct anterior holdfast organ • often armed with hooks and/or • equipped with suckers and bothria that function like suction cups • Neck • posterior to the scolex • proglottids are continuously produced • Strobila • consisting of individual proglottids • each proglottid comprises one or more sets of reproductive organs.
23/07/2023 21 46 • As the cestode matures, the segments are shifted towards the posterior end of the individual and are separated • They lack a digestive system and absorb nutrients through their neodermis. • Like other flatworms, cestodes use protonephridia (flame cells), located in the proglottids, for excretion. • Ootype receives eggs, sperm, and yolk cells from the ovovitelline duct • Cirrus sac: a pouch or channel containing the copulatory organ (cirrus) in certain invertebrates. Morphology Hermaphroditic polyzoic flatworms Pork cestode Taenia solium 48 General Cestode Life Cycle a) The hermaphroditic adults live, attached with the scolex, within the intestine of their final hosts (e.g. Ursidae, Pinnipedia, piscivore birds, planktivore andpiscivore fishes, humans). b) Operculated eggs are directly excreted unembryonated or from detached proglottids and transported into the water with the hosts faeces. c) Within the water column, they develop over a time span dependent on the water temperature. From this egg, the coracidium larva containing the oncosphere, which is endowed with six hooks, hatches. d) The coracidium is ingested by the first intermediate host-small crustaceans (e.g. Cyclopoida, Amphipoda, Euphausiacea).
23/07/2023 22 49 General Cestode Life Cycle (e) Within the crustaceans, it develops into the procercoid larva. (f) The infected crustaceans are ingested by the next paratenic host (small fish, Cephalopoda), where they penetrates the intestine wall and bore into the muscle and body tissue where they develop into plerocercoid larvae. The infected second intermediate hosts are then either eaten directly by the final host or … (g) …another paratenic host, where the plerocercoid larvae can accumulate within the tissue. The last paratenic host is then eaten by the final host, where the plerocercoid larvae enter the digestive system and rapidly grow into adults. Multiple cestoda species are able to carry out their life cycle within several final hosts, while in accidental hosts, the plerocercoid larvae accumulate and migrate through the body 50 Development
23/07/2023 23 Diphyllobothrium Diphyllobothrium is a zoonotic parasite that can infect both animals and humans. Two primary hosts The life cycle of Diphyllobothrium involves two primary hosts: fish and humans. Adult diphyllobothrium worms reside in the small intestines of fish-eating mammals. Infection in fish Fish that eat infected copepods containing the larvae get infected with the Diphyllobothrium tapeworm. Infection in humans Humans get infected with diphyllobothrium when they consume raw or undercooked fish infected with plerocercoid larvae.
23/07/2023 24 Diphyllobothriasis Diphyllobothriasis is a parasitic infection caused by the ingestion of raw or undercooked fish that are infected with tapeworm larvae. Common symptoms include abdominal pain, diarrhea, and weight loss. This infection can be prevented by thoroughly cooking fish and freezing it at -4 F for at least 7 days. Treatment typically involves the administration of a single dose of an antiparasitic drug. It is important to be aware of the risks of consuming raw or undercooked fish, as it can lead to serious health complications. Diphyllobothriasis: Adverse Effects Diphyllobothriasis, an infection caused by Diphyllobothrium tapeworms, can have several adverse effects on human health. This section describes some of these effects. Diphyllobothrium tapeworms disrupt vitamin B12 absorption, leading to anemia and various neurological symptoms. Prolonged infection with Diphyllobothrium tapeworms causes anemia due to vitamin B12 deficiency and competition for nutrients in the digestive tract. In severe cases, the tapeworms can consume significant amounts of the host's nutrients, leading to malnutrition and related health problems. 1 Vitamin B12 deficiency 2 Anemia 3 Malnutrition
23/07/2023 25 Digenea • Classification • Kingdom: Animalia • Phylum: Platyhelminthes • Class: Trematoda • Subclass: Digenea • Together with the Aspidogastrea, the Digenea form the class Trematoda and represent by far the most diverse taxon within the group of internal metazoan parasites. • Digenean trematodes are endoparasites with obligatory hosts, a generational change, and complex life cycles that may vary considerably among the taxa. • Many species from terrestrial and freshwater habitats are of significant medical importance (e.g. Schistosoma spp.) and pose a major threat to the health of both animals and humans. Trematode Flukes - Digenea Adults commonly occur in the alimentary tract of all classes of vertebrates. In fish, they might also occur under the scales, on/in the eyes, gills, in the swim/urinary/gall bladder, the body cavity, the musculature, ovaries and circulatory system. Most digeneans have an oral sucker, opening into a blind gastrointestinal tract, and a ventral sucker which is used only for attachment. However, the latter is also absent in many species.
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23/07/2023 27 (a–i) Some common types of cercariae. (a) Amphistome cercaria (Ophthalmocercaria). (b) Monostome cercaria. (c) Echinostome cercaria. (d–f) Xiphidiocercariae, (d) Microcercous cercaria, (e) Xiphidiocercaria, (f) Cotylocercous cercaria. (g) Trichocercous cercaria. (h, i) Furcocercous cercariae, (h) Gasterostome cercaria, (i) Apharyngate cercaria. EY eyespot, HD head, IN intestine, OS oral sucker, PH pharynx, SP tegumental spines, ST stylet inside the oral sucker, TA tail, VS ventral sucker
23/07/2023 28 (a) The hermaphroditic adults live within the gastrointestinal tract of the final hosts (e.g. planktivore and piscivore fishes, piscivore birds). or (e) infect another intermediate host (e.g. Pisces, Chaetognatha, Crustacea: Cyclopoida, Amphipoda, Euphausiacea) where they transform into metacercariae, which mature over time until the intermediate host is ingested by the final host (b) Eggs are excreted by the final hosts through faeces and contain a miracidium. Egg size and shape vary with species. (c) The egg is ingested by the first intermediate host (aquatic snails), and the miracidium hatches inside its intestine or the miracidium hatches in the water column and actively penetrates the molluscs. (d) Within the snail, the miracidium penetrates the hepatopancreas (digestive gland) and transforms into a redia or sporocyst (depending on the species). These form cercaria, which are released into the water and can directly infect the final host (ingestion or penetration of the skin) General Digenea life cycle. Clonorchiasis How it's Contracted Clonorchiasis is caused by consuming raw or undercooked freshwater fish infected with the larvae of the liver fluke Clonorchis sinensis, which becomes infected through freshwater snails acting as intermediate hosts. Symptoms While most cases do not show any symptoms, some cases can cause abdominal pain, diarrhea, nausea, vomiting, fatigue, and an enlarged liver. Prevention To prevent contracting Clonorchiasis, proper food handling and cooking practices should be followed.
23/07/2023 29 Clonorchis sinensis `the chinese liver fluke’ Endemik (Japan, China, Taiwan) 1st intermediate host: snail (Parafossarulus manchouricus) 2nd intermediate host: fish (>100 sp) Final host: human mammal
23/07/2023 30 Geographic distribution Clonorchis sinensis is prevalent in various regions of East Asia, particularly in China, Korea, Vietnam, and parts of Southeast Asia. The distribution of the parasite is closely associated with traditional dietary habits, such as the consumption of raw or undercooked freshwater fish. . Life cycle The life cycle of Clonorchis sinensis involves several hosts. The adult worms reside in the bile ducts of definitive hosts, which are usually humans, dogs, cats, and other fisheating mammals. These animals shed eggs containing miracidia into the environment through their feces. Intermediate hosts Freshwater snails serve as the first intermediate host for Clonorchis sinensis. The eggs containing miracidia hatch in water and infect the snails. Inside the snails, the miracidia develop into sporocysts, rediae, and finally, into infective cercariae. Clinical manifestations Known as clonorchiasis. In the early stages, the infection may be asymptomatic or cause mild gastrointestinal symptoms. However, chronic infection can lead to complications such as inflammation of the bile ducts (clonorchitis), bile duct obstruction, and bile duct cancer (cholangiocarcinoma). Diagnosis Clonorchis sinensis infection in humans can be challenging, as symptoms may be nonspecific and similar to other liver or gastrointestinal disorders. Laboratory tests, including the examination of stool samples for parasite eggs and specific serological assays, can aid in the diagnosis Treatment Treatment for clonorchiasis involves the use of anthelmintic drugs to eliminate the adult worms. Praziquantel is the most commonly used drug for this purpose. In cases of advanced disease or complications like cholangiocarcinoma, additional medical interventions may be necessary. Clonorchis sinensis Metagonimiasis Metagonimiasis is a parasitic infection caused by the consumption of raw or undercooked fish that are infected with the Metagonimus fluke. Common symptoms include abdominal pain, diarrhea, and fever. This infection can be prevented by cooking fish thoroughly and practicing good hygiene. Treatment typically involves the administration of an antiparasitic drug.
23/07/2023 31 Opisthorchiasis 1 How it's Contracted Opisthorchiasis is another parasitic infection caused by consuming raw or undercooked freshwater fish. It is caused by the liver flukes of the Opisthorchis genus. Symptoms 2 Symptoms of opisthorchiasis often do not appear in its early stages. However, once the symptoms start showing up, they can cause abdominal pain, diarrhea, nausea, vomiting, fever, fatigue, and jaundice. 3 Prevention Consuming properly cooked fish and avoiding certain regions where the disease is common in freshwater fish can prevent Opisthorchiasis.
23/07/2023 32 Opishorchis viverini `Southeast Asia liver fluke’ Lao, Vietnam, Thailand Final host: dog & cat 1st intermediate host: snail (Bithynia sisnensis) 2nd intermediate host: cyprinid (> 35 sp) Opishorchis felineus `Cat liver fluke’ Rusia `siberian liver parasite’ (liver,gall-bladder & pancreas’ àcirrhosis àliver cancer) Infected raw fish, slightly salted & frozen fish Final host: cat 1st intermediate host: snail 2nd intermediate host: freshwater fish (>35 sp) Human infection Humans can become infected with Opisthorchis flukes by consuming raw or undercooked freshwater fish containing the infective metacercariae. Once ingested, the metacercariae excyst in the small intestine, and the larvae migrate to the bile ducts, where they mature into adult worms. Life cycle The life cycle of Opisthorchis flukes involves several hosts. Adult worms reside in the bile ducts of definitive hosts, which are usually fish-eating mammals, including humans, cats, dogs, and other carnivores. The adult worms release eggs into the bile ducts, which are then passed out with the host's feces into the environment Intermediate hosts Fish, particularly freshwater fish, serve as the second intermediate host for Opisthorchis flukes. The cercariae are released from the snails into the water and penetrate the fish's skin, where they encyst and develop into metacercariae Clinical manifestations Opisthorchiasis infection can cause a range of clinical symptoms and complications. In the early stages, the infection may be asymptomatic or cause mild gastrointestinal symptoms. Chronic infection can lead to inflammation of the bile ducts (opisthorchitis), bile duct obstruction, and bile duct cancer (cholangiocarcinoma Diagnosis Diagnosing Opisthorchiasis can be challenging, as the symptoms may be nonspecific and similar to other liver or gastrointestinal disorders. Laboratory tests, including the examination of stool samples for parasite eggs and specific serological assays, can aid in the diagnosis Treatment Treatment for Opisthorchiasis involves the use of anthelmintic drugs to eliminate the adult worms. Praziquantel is the most commonly used drug for this purpose. In cases of advanced disease or complications like cholangiocarcinoma, additional medical interventions may be necessary. Opishorchis sp.
23/07/2023 33 Digenea From Marine Fishes https://www.newscientist.com/article /2129880-parasite-living-inside-fish-eyeballcontrols-its-behaviour/#ixzz7BZpVXP9x Larvae of the eye fluke, Diplostomum, emerge from snails and infect fish by penetrating skin or gills, then move to the lens where they may impair the vision of the fish. For the fluke to reproduce, a bird must eat the infected fish, and it has been suggested that they therefore actively manipulate the fish’s behaviour to increase the risk of predation. The trematode genus Diplostomum contains several common parasites infecting the eyes of freshwater and brackish water fish and thus they are called eye flukes
23/07/2023 34 Besides the health risk due to the zoonotic potential of some parasite species, the presence of visible parasites alone poses an aesthetical problem and thus affects the marketability of commercially produced fish. In order to avoid heavily infected fish on the market, measures are taken to either: • reduce the infection level • sort out visibly infected fish. Several handling steps may be performed by processors: heading, gutting, filleting, skinning and trimming. MARKETABILITY Zoonotic Parasite Control Environmental Management Efficiently manage animal habitats and ecosystems to reduce the risk of disease transmission. Vector Control Monitor and control insect vectors like mosquitoes that can transmit zoonotic parasites. Health Education Provide education and training to healthcare workers, researchers, and the public on the dangers of zoonotic parasites and prevention measures. Vaccine Development Support research and development of vaccines to prevent zoonotic parasitic diseases in animals and humans.
23/07/2023 35 Monitoring Techniques for Zoonotic Parasites 1 Serological Surveys Use blood samples to detect antibodies against zoonotic parasites. 2 Data Integration and Analysis Combine ecological, epidemiological, and social data to evaluate the risk of disease transmission. 3 Environmental Surveillance Monitor animal habitats and vectors to detect disease transmission early. 4 Syndromic Surveillance Monitor animal and human health factors that could indicate an outbreak, such as fever or diarrhea. Experimental Research on Zoonotic Parasites from Fish In vitro Studies Investigate the biology of zoonotic parasites under laboratory conditions. Experimental Infections Infect fish and other animal models under controlled conditions to assess disease transmission and pathogen-host interactions. Epidemiological Studies Explore the transmission patterns and risk factors of zoonotic parasites in humans and animals.
23/07/2023 36 Drug-resistant Parasites Misuse of Antimicrobials The overuse and misuse of antimicrobial agents can lead to the development of drug-resistant parasites. Mutations and Adaptations Zoonotic parasites can undergo genetic mutations or adaptations that enhance their ability to infect and transmit between hosts. Challenges in Diagnosis and Treatment Infections by drug-resistant parasites are often challenging to diagnose and treat, and could pose substantial long-term consequences on human and animal health. Preventive Measures Against Fish-borne Diseases Preventing fish-borne zoonotic diseases involves adopting good food safety practices, proper cooking techniques, and implementing strict regulations and monitoring of fish production and handling. Awareness-raising among communities is a crucial aspect of reducing the burden of these infections. 1 Regulations and Standards Ensuring strict regulations and monitoring fish production, handling, processing, and distribution. 2 Proper Cooking Techniques Adopting good food safety practices and proper cooking techniques, such as cooking fish to an internal temperature of at least 145 F for fish safety. 3 Frequent Cleaning and Disinfection Cleaning and disinfection of fish processing areas, equipment, and utensils to prevent cross-contamination. 4 Education and Awareness Raising awareness among communities, consumers, and food handlers to ensure proper handling of fishery products, adequate cooking, and optimal storage conditions.
23/07/2023 37 Prevention Measures Against Fish-borne Diseases One Health Approach A strategy involving medical practices, veterinarians and environmental practices to control the spread of zoonotic parasites. Surveillance and Early Detection Prevention is keys to eradicating the spread of parasitic diseases by monitoring and detecting new trends and outbreaks. Veterinary and Human Healthcare Collaboration Effective collaboration is crucial in controlling the spread of zoonotic parasites and eradicating the spread of parasitic diseases. Personal Protective Measures Using personal protective equipment helps in preventing the spread of zoonotic parasitic diseases by reducing exposure to them. Regulation 853/2004: sets out rules for foodstuff that may constitute hazard to human health and require specific hygienic rules. Regulation 853/2003: ensures food business operators must not place fishery products infected with parasites on the market intended for human consumption. European Food Safety Authority (EFSA): appointed to • (a) assess food safety concerns associated to parasites that may be present in fishery products, • (b) evaluate alternative treatments for killing viable parasites in fishery products and evaluate their effectiveness compared to the freezing method described in the hygiene regulations • (c) set criteria when products are eaten raw, almost raw or cold-smoked from fishing grounds and from aquaculture ⚬ do not present a health hazard due to the presence of parasites. REG ULAT I ONS & C RI T ERI A EUROPEAN UNION
23/07/2023 38 REG ULAT I ON EC (2 0 0 5 ) 2 0 7 4 /2 0 0 5 VISUAL INSPECTION FISH LANDINGS • non-destructive examination of fish and fishery products under good light conditions • check for parasites during handlings of fishery products on land or on board of the vessels. FISH HANDLING • inspection of eviscerated fish must be carried out by an experienced person with a sufficiently high number of samples • focused on the abdominal cavity, liver and roe intended for human consumption. FISH FILLET/SLICES • visual inspection must be performed during trimming and after filleting/slicing, either by individual examination or according to a sampling plan. FISH CANDLING • placing fish on a light table in a darkened room • should be used by • the fish processing industry and be included in the sampling plan if necessary WEAKNESS successful nematode larvae detection varies: • fillet thickness • presence of skin on fillet • oil content • pigmentation • operator experience MEAS UR ES TO IN AC TIVATE PAR AS ITES IN F IS H REGULATION 853/2004 Food business operators must ensure that fishery products intended for raw or almost raw consumption undergo a freezing treatment that ensures killing viable parasites. This regulation was extended with some specifications based on the scientific advice of the EFSA in EC Regulation 1276/2011.
23/07/2023 39 Freezing or heating • Effective measures to inactivate viable parasites • Duration and temperature of the freezing treatment must consist of at least 20 C for 24 H or 35 C for 15 H in all parts of the product in order to kill parasites other than trematodes • Must be applied for fishery products derived from finfish and cephalopod molluscs, which are consumed raw or almost raw. • Cold-smoked fish (less than 60 c) and all marinated and/or salted fishery products must be frozen • If the processing is insufficient to kill nematode larvae. Pickling & marinades • Since nematodes live in stomachs of adult mammals, they are relatively robust against acid. • Pickling and marinades duration depends on salt concentration until the larvae are killed • Viability tests on nematode larvae must be conducted after artificial digestion of salted atlantic herring and salted sprat. Post-mortem migration • Nematode larvae migrate from the viscera into the musculature • Immediate gutting after capture is mandatory for most marine fish species to avoid an increased number of nematodes in the fish musculature. • Demonstrated for, e.g. Herring, smelt, anchovy and capelin • No evidence of postmortem migration in haddock (melanogrammus aeglefinus), ocean perch (e.G. Sebastes marinus) and alaska salmon (Oncorhynchus keta, O. Gorbuscha, O. Nerka). Heating or cooking • > faster than freezing: at a core temperature of >60 C, • duration of at least 1 min is recommended. INACTIVATING PARASITES IN FISHERIES PRODUCTS Future Directions and Challenges 1 Anticipated Challenges Emergence of new parasites or strains that are resistant to current prevention, diagnostic, and treatment measures. 2 Advancements in Parasitology Research New technologies like CRISPR, gene editing, and genotyping techniques will transform the study of parasitic diseases and improve diagnostic, treatment, and control measures. 3 The Role of Technology and AI AI can be used to identify patterns and design control measures in ways that were previously impossible with traditional means.
23/07/2023 40 TQ Q&A Session
23/07/2023 1 S A I R A T U L D A H L I A N I S I S H A K Institute of Tropical Aquaculture & Fisheries, Universiti Malaysia Terengganu FISH ANATOMY & QUALITY ASSESMENT INTRODUCTION 'Sensory quality is a complex set of sensory characteristics, including appearance, aroma, taste and texture, that is maximally acceptable to a specific audience of consumers, those who are regular users of the product category, or those who, by some cleardefinition, comprise the target market.’ (Fishken, 1990) Sensory qualities assessed: appearance, taste, odour, flavour and texture present (York & Sereda, 1994)
23/07/2023 2 GOALS IDENTIFY Methods for fish quality evaluation DETERMINE Select suitable application for different techniques on any samples KNOWLEDGE Be a better evaluator with quality assesment techniques gained GENERAL ANATOMY OF EDIBLE AQUATIC ORGANISMS 2
23/07/2023 3 Fish Squid / Cuttlefish
23/07/2023 4 Prawn / Shrimp Crab
23/07/2023 5 Bivalves Importance Of Quality Assessment Of Fish 3
23/07/2023 6 OBJECTIVE OF ASSESSMENT Avoid avoid the ingestion of contaminated food Evaluate evaluate the nutritive value of food Ensure ensure the safety of the consumer Prevent Loss of profitability by businesses Qualities Attribute to Raw Fish 4