Abstract
Histomonas meleagridis is a flagellate protozoan parasite living in the cecum of birds digestive system and is the causative agent of histomoniasis. In this study 110 poultry fresh stool samples were assessed in order to detect H. meleagridis, and egg or adult worm of Heterakis gallinarum in Lorestan province, Iran. The results showed that the prevalence of H. meleagridis was 31%. Also, 19.5% of infected poultry had a watery stool. The eggs or adult worms of H. gallinarum were not seen in any of the samples. The results showed the high prevalence of this parasite, and the factors such as temporary hosts, susceptible hosts, and cloacal transmission with the involvement of water containing the parasite are the effective risk factors in prevalence. It is better to considered H. meleagridis as waterborne parasites, so further epidemiological studies on other birds are suggested to determine the parasite pathogenic strains using molecular methods.