Swine Helminths Flashcards
what are the gastrointestinal helminths of swine?
nematodes
small intestine: ascrais suum, strongyloides sp
large intestine: trichuris suis
stomach: hyostrongylus
what is the major gastrointestinal nematode in pigs?
ascaris suum
what are the clinical signs of ascaris suum?
unthriftiness
weight loss or not gaining weight
coughing, rapid shallow breathing- “thumps”
colic
true/false: ascaris suum eggs are hardy and sticky and difficult to get rid of
true
what are the pathophysiology signs of ascaris suum?
L3, L4: migration:
liver: interstitial hepatitis, localized fibrotic area
lungs: hemorrhage, bronchitis, edema, pneumonia
L4: small intestine: catarrhal enteritis, rarely obstruction/perforation
is ascaris suum zoonotic?
yes
is strongyloides ransomi zoonotic?
no
how is strongyloides ransomi transmitted?
transmammary
what are the clinical signs of strongyloides ransomi?
piglets: bloody diarrhea, emaciation, anemia, stunteted growth, death
adults: usually none
what is the prepatent period of strongyloides ransomi?
2-4 days if transmammary
6 is skin or mucosal penetration
what is the life cycle of strongyloides ransomi?
direct
alternates between free-living and parasitic
what is the pathophysiology of strongyloides ransomi?
piglets especially
acute enteritis
pulmonary migration
+/- lesions from percutaneous or mucosal transmission
what are the clinical signs of trichuris suis?
primarily 2-6mo piglets
diarrhea
anemia
weight loss
what stage is infectious in pigs of trichuris suis?
L1
what is the life cycle and prepatent period of trichuris suis?
direct
6-7 weeks
where do hyostrongylus rubidus go in the body?
stomach
what are the clinical signs and pathophysiology of hyostrongylus rubidus?
older swine on pasture
diarrhea, vomiting, anorexia, wasting
larvae invade gastric glands, gastritis
what are the clinical signs of metastrongylus spp?
cough, shallow breathing, anorexia
piglets worse
what is the pathophysiology of metastrongylus spp?
alveolitis, bronchitis, possible tracts in liver
what does stephanurus sp infect?
retroperitoneal tissues and kidneys, ureters
what are the clinical signs of stephanurus sp?
anorexia
weight loss
what is the pathophysiology of stephanurus sp?
inflammation
abscesses due to larval migration
what cells do trichinella spiralis inhabit?
small intestine mucosa: females deposit prelarvae
prelarvae to blood stream to myocytes: “nurse cells”
is trichinella spiralis zoonotic?
yes
what are the hosts of taenia solium?
swine are intermediate hosts
humans are definitive hosts, accidental intermediate hosts
what life cycle do taenia solium have?
predator-prey
what parasites have an L1 infectious stage?
Trichuris suis
Trichinella spiralis
what are the respiratory helminths of swine?
Metastrongylus spp
what are the urinary helminths of swine?
Stephanurus sp
what are the musculoskeletal helminths of swine?
Trichinella spiralis
Taenia spp
what are the hosts of ascaris suum?
swine
paratenic: earthworm, beetle
you see “milk spots” on a liver of a pig on necropsy. what parasite(s) are you worried about?
Ascaris suum
Stephanurus dentatus
Metastrongylus does not migrate in liver extensively
what can be used to treat Ascaris suum?
multiple options: fenbendazole, levamisole, pyrantel tartarate, ivermectin
what can be used to treat Strongyloides ransomi?
benzimidazoles, avermectins, especially prior to farrowing
what is the intermediate host of Metastrongylus spp?
earthworm
how is Metastrongylus spp diagnosed?
eggs with L1 in feces
necropsy: bronchial tree
what is the life cycle of Stephanurus spp?
indirect
earthworm
what can a swine get from eating earthworms?
Stephanurus spp
Metastrongylus spp
Ascaris suum (paratenic)
what is a parasite that has no signs in swine but does have signs in other species?
Trichinella spiralis
Taenia solium maybe: swine IH, humans DH
what swine parasites have no treatment?
Trichinella spiralis
