Fat of the wild avian filarial nematode Chandlerella quiscali (Onchocercidae: Filarioidea) in the domestic chicken.

Chandlerella quiscali is a filarial nematode parasitizing the brain of the common grackle (Quiscalus quiscula versicolor), blue jay (Cyanocitta cristata bromia), brown-headed cowbird (Molothrus ater ater), and starling (Sturnus vulgaris). Filarial infections of many wild bird species are common but natural infections of domestic fowl are rare. The habits of many wild birds commonly bring them in close association with domestic poultry. Because of the high prevalence of C. quiscali in grackles (98%) and the pathogenesis it might cause in an unnatural host, this parasite was used to test the receptiveness of the domestic chicken as a host. Microfilariae of C. quiscali were injected into chickens and adult worms were transplanted into the brain or body cavity of other chickens. One group of experimental chickens was immunosuppressed (IS) while another group was not immunosuppressed (NIS). Microfilariae circulated in the blood of IS and NIS chickens for at least 56 days. There was no significant difference in the number of microfilariae recovered from IS and NIS chickens. Adult worms were encapsulated in the brain of NIS chickens and in the body cavity of IS and NIS chickens. Worms survived for 36 hr in the brains of IS chickens. Past 36 hr the worms were shriveled and dead, apparently the result of a physiological and/or nutritional deficiency in the brain.