Clinico-Pathological Study of Avian Coccidiosis and its Economical Impact on Small Scale Poultry Farming in Selected Districts of Tigray, Ethiopia

摘要

Despite the economic significance of coccidiosis in the study area (Tigray region, Ethiopia), no substantial research have been done. Hence, the present study was designed to provide information on the clinico-pathology and socioeconomic impacts of avian coccidiosis on chickens farmed under small-scale system. Clinico-pathomorphological study, morphometric Oocyte Per Gram (OPG) determination and questionnaire survey were done. Out of 2000 chicken populations, 350 (17.5%) showed clinical coccidiosis clinico-pathomorphological study and 5% mortality rate was reported. The major clinical findings were depression, bloody diarrhea, mucoid droppings and loss of production. Eleven percent of birds examined through necropsy showed mild to moderate thickened, wrinkled and edematous intestinal wall with multiple focal, ecchymotic haemorrahge and congestion and with mucoid content. Seven percent of samples reported to have greatly enlarged and distended caecal pouch with clotted blood and diffused haemorrhagic enteritis. Histopathological examinations of 8.5% of the representative tissue sections showed numerous oocytes invading the mucosal and submucosa layers, loss of enterocells, hemorrhage, necrosis of mucosal layer, infiltration of heterophils and lyphocytes in the submucosal, desqumation and blunting of villi. On morphometric examination, out of 96, 31 and 51 droppings, litter and intestinal content samples, 66 (68.75%), 8 (25.81%) and 39 (76.47%) were found positive for coccidian oocytes, respectively. The questionnaire based survey indicated an estimated 1,375 Birr loss per farm per month due to coccidiosis. Risk factors such as poultry farmers/employees with little background on poultry production and poor litter management were found to favour the occurrence of avian coccidiosis. Integrative poultry producer education/extension service and participatory coccidiosis control and prevention approaches need to be in place.