Hexamita and Histomonas Flashcards
Histomonas meleagridis
anaerobic protzoan of gallinaceous fowl
Disease caused by Histomonas meleagridis in turkeys?
Blackhead disease
Most common route of Histomonas meleagridis transmission?
indirect via a cecal nematode Heterakis gallinarum
Paratenic/transport host of H. meleagridis?
earthworms! (also house and flesh flies, grasshoppers)
Are there any H. meleagridis cysts?
no
Lesions from H. melagridis
cecal lesions with yellow caseous smelly exudate
bulls-eye lesions on liver (areas of coalescing necrosis with depressed centers)
Clinical Signs of H. meleagridis
Blackhead (due to poor oxygenation of blood), sulfur-yellow diarrhea, hunched appearance, ruffled
Mortality of H. meleagridis in young turkeys?
High (50-100%)
Clocal drinking
another route of transmission in turkeys and chickens, when the bird sits on feces
Characteristic appearance of H. meleagridis on histology?
space around liver parenchymal cells
Can chickens and turkeys be raised together?
nah, not a great idea
The new name for Hexamita?
spironucleus
Disease of Hexamita meleagridis?
Spironucleosis; causes acute catarrhal enteritis in birds (but not chickens)
Main route of Spironucleosis transmission?
fecal-oral
Infectious stage of spironucleus?
trophozoites
