Experimental inoculation of day-old ducks with Brachyspira pilosicoli and B. alvinipulli

Two groups of one-day-old Peking ducklings (Groups I and II, 12 birds/group) were inoculated orally with Brachyspira pilosicoli and two groups with B. alvinipulli (Groups III and IV, 12 birds/group). T-2 toxin was added to the feed of Groups II and IV in a dose of 1 mg/kg of feed. Groups V and VI served as uninfected control groups (ducks of Group VI received T-2 toxin). The body weight gain of the ducks was measured and clinical signs were monitored continuously. The birds were sacrificed and necropsied on days 7, 14, 21, and 28 post infection (PI). The liver, spleen, kidney, thymus, bursa of Fabricius, ileum, caecum and colon were examined histologically. Culturing of Brachyspira spp. and immunohistochemistry were performed from the sampled parts of the intestines as well. No gross pathological or histological lesions that could be associated with B. pilosicoli or B. alvinipulli were detectable in the intestinal mucous membrane including the colonised intestinal glands. Mortality did not occur during th...