Using the HmL1 strain of Histomonas meleagridis in evaluating chemotherapeutants in chicks

Ten-day-old White Leghorn cockerels were inoculated per cloaca with 500,000 culture forms of the HmL1 strain of Histomonas meleagridis. Birds dying on the 6th and 7th days and birds necropsied 7 days postinoculation had prominent cecal and liver lesions indicative of severe histomoniasis. Dose responses were obtained with three 1,2-disubstituted 5-nitroimidazoles blended into the feed at various concentrations, demonstrating the utility of this virulent strain in chemotherapy studies.