Fascioloa gigantica 20% Flashcards
what are they (fascioloa)
large flukes in bile duct of animals and man
reservoir hosts (fascioloa)
Sheep, goats, cattle, roe deer and lagomorphs. Fasciola sp. are not found in North American deer.
escape from host (fascioloa)
Adults in the bile ducts release eggs which are passed in the feces.
transmission (fascioloa)
snails, he host ingests the metacercaria which excysts in the small intestine. The resulting immature fluke then penetrates the wall of the intestine and migrates to the surface of the liver where it penetrates the liver and migrates in the parenchyma for eight weeks before it enters a bile duct and matures.
susceptible hosts (fascioloa)
Sheep, goats, cattle, roe deer, lagomorphs, swine, horses and man
incubation period (fascioloa)
Highly variable depending on worm burden. Prepatency is approximately two months.
age, season (fascioloa)
rainy season, All ages equally susceptible on first exposure. Considerable resistance develops in adult reservoir animals which are reinfected annually. Therefore young animals carry the largest worm burdens and produce the greatest numbers of eggs. Humans are equally susceptible at all ages.
mortality (fascioloa)
Human mortality is rare. Animal mortality depends on the parasitic burden and development of clostridial toxins.
Cattle which have not been vaccinated may suffer high mortality rates from bacillary hemoglobinuria, whereas sheep which have not been vaccinated may suffer heavy losses from black disease.
zoonotic (fascioloa)
yes
Treatment (fascioloa)
Treatment of domestic livestock, particularly ruminants in endemic areas. Discourage consumption of aquatic vegetation.
Snail control with chemicals in areas associated with permanent waters.
medication (fascioloa)
Albendazole
Bithionol
clinical signs (fascioloa)
anemia, anorexia
