Parasites by Host: Pig & Poultry (PDF)

PARASITES BY HOST: PIG & POULTRY  BY THE END OF THIS PRESENTATION, YOU SHOULD BE ABLE TO: Provide a differential list of parasites that cause the clinical signs reported in the host Generate a diagnostic plan to rule in or out parasites on the differential list, and what...

PARASITES BY HOST: PIG & POULTRY  BY THE END OF THIS PRESENTATION, YOU SHOULD BE ABLE TO: Provide a differential list of parasites that cause the clinical signs reported in the host Generate a diagnostic plan to rule in or out parasites on the differential list, and what the expected findings would be for each test Design a treatment plan depending on the parasite affecting the host Inform owners regarding methods of prevention of future infections by these parasites MY PIG IS ITCHING Arthropods > Insecta > Siphonaptera (fleas) > Pulex PULEX Human flea Also affects swine and dogs No genal or pronotal combs Arthropods > Insecta > Phthiraptera (lice) > Anoplura (sucking lice) > Haematopinus HAEMATOPINUS All tarsal claws equal size Sclerotized lateral margins Can be vector for swinepox virus H. asini: Horses H. suis: Pigs H. eurysternus, H. quadripertusus, H. tuberculatus: Cattle H. eurysternus: Common in North America Can cause severe anemia H. quadripertusus: Tropical and subtropical areas H. tuberculatus: Old World MY PIG HAS DIARRHEA Protists > SAR > Apicomplexa > Coccidians > Cystoisospora CYSTOISOSPORA SPP. IN PIGS Cystoisospora suis Sporulated oocysts acquired by neonates from sows Neonatal coccidiosis in 1-2 week old pigs Diarrhea, dehydration, weight loss Prepatent period 5 days  ACANTHOCEPHALANS Macracanthorhynchus hirudinaceus: Lives as adult in small intestine in pigs Can occasionally infect dogs Females up to 35 cm long, males smaller Dung beetles act as intermediate hosts Pigs can develop diarrhea, emaciation, and abdominal pain Rare gut perforation described Diagnosis: Thick, multilayered eggs with a dark brown shell on fecal flotation or sedimentation Adults can be passed in feces Treatment: Benzimidazoles, macrocyclic lactones MY PIG IS COUGHING  ACTIVE LEARNING ACTIVITY List some causes of coughing in pigs, and what tests you could run to rule in or out your differentials. Nematoda > Secernetea > Strongylida (bursates) > Metastrongyloidea (lungworms) > Metastrongylus METASTRONGYLUS Live as adults in the bronchi and bronchioles of swine Females lay eggs containing first-stage larvae Develop into infective larvae in earthworm intermediate host Disease: Can cause coughing with bronchitis and bronchiolitis Diagnosis: Larvated eggs on fecal flotation Treatment: Fenbendazole, levamisole, ivermectin, doramectin Nematoda > Secernetea > Ascaridia (roundworms) > Ascaris ASC ARIS SUUM Lives in small intestine of swine host Acquired through ingestion of third-stage larvae in eggs from contaminated environment Earthworm and dung beetle paratenic hosts Disease: Hepatic fibrosis (milk spots) Lung hemorrhages and audible breathing efforts (thumps) Diarrhea, rare bowel wall perforation Diagnosis: Eggs on fecal flotation Treatment: Hygromycin B, piperazine, dichlorvos, fenbendazole, levamisole, ivermectin, doramectin, pyrantel tartrate Pyrantel tartrate approved for treatment of infective larvae immediately after hatching THERE ARE BUGS ON MY CHICKENS  ACTIVE LEARNING ACTIVITY Name some ectoparasites of chickens and what they would look like morphologically Arthropods > Insecta > Siphonaptera (fleas) > Echidnophaga ECHIDNOPHAGA Sticktight flea Affects poultry, dogs, cats, rabbits, horses, humans Around eyes and cloaca, combs and wattles No genal or pronotal combs Ctenocephalides felis also a common infestation in cats Arthropods > Insecta > Phthiraptera (lice) > Mallophaga (chewing lice) MALLOPHAGA (CHEWING LICE) Chewing lice Stout mandibles, broad heads Common in poultry Feed on epidermal scales, feathers, and sebaceous secretions Some are blood feeders (i.e. Heterodoxus spiniger in dogs) Arthropods > Arachnids > Acari > Mesostigmata > Dermanyssus DERMANYSSUS GALLINAE Mites of poultry Long slender chelicerae, small chelae Hide in nests and roosts during day, attack at night Generation time as fast as 1 week Adults can survive unfed for months Blood loss can kill nestlings and reduce egg production Arthropods > Arachnids > Acari > Mesostigmata > Ornithonyssus ORNITHONYSSUS Mites of poultry and rodents Stout chelicerae Gut is dark red to black Remain on host most of the time Can cause significant blood loss Arthropods > Arachnids > Acari > Astigmata > Knemidocoptidae > Knemidocoptes KNEMIDOKOPTES Knemidokoptes mutans: Females lack pretarsi, males have pretarsi similar to Sarcoptes spp. Causes “scaly leg” in chickens, turkeys, and pheasants Mites burrow in epidermis and cause scales to lift and become loosened Condemnation of legs and feet cause economic losses Knemidokoptes gallinae: Depluming mite of chickens, pigeons, pheasants, and geese Intense pruritus leads to feather pulling MY CHICKENS HAVE DIARRHEA Protists > SAR > Apicomplexa > Coccidians > Eimeria EIMERIA Poultry: Significant issue with multiple pathogenic species Eimeria tenella and Eimeria necatrix most pathogenic Can cause severe diarrhea and high mortality Eimeria tenella is found in the cecum, and produces cecal cores or clotted blood and necrotic tissue Eimeria necatrix is found in the small intestine and causes white spots on mucosa Control through anticoccidial compounds in feed and water or vaccination with live vaccines Protists > SAR > Apicomplexa > Coccidians > Eimeria EIMERIA Overall control measures: Drugs often not helpful in treating coccidiosis by the time oocysts are detected in feces Supportive care for diarrhea Prophylactic treatments allow host to develop immunity after exposure without developing clinical disease Prophylacitc treatments do not prevent infection Coccidiostatic drugs such as amprolium useful to inhibit coccidial growth and minimize clinical signs MY CHICKENS ARE GASPING Nematoda > Secernentea > Strongylida (bursates) > Strongyloidea > Syngamus SYNGAMUS AKA Gapeworm Large buccal capsules Males and females permanently joined, making a “Y” shape Lives as adults in upper respiratory tract of birds Infection via direct ingestion of infective eggs or earthworm paratenic hosts Disease: Can cause verminous pneumonia, gasping, choking, emaciation, and suffocation due to obstruction Diagnosis: Eggs with bipolar plugs in fecal flotation Treatment: Ivermectin, fenbendazole PRACTICE QUESTIONS