The effect of administration of anti-coccidial drugs on oocyst shedding and performance in experimental coccidiosis in broiler chickens.

Coccidiosis is one of the major parasitic diseases of poultry. In this study, to compare the effects of coccidiostatic drugs on fecal oocyst shedding and body weight gain of coccidi-infected broiler chickens, 180 one day old Ross 308 broiler chicks were randomly assigned to four treatments. Each treatment contained 3 replicates of 15 chickens. Treatments 1 and 2 were fed diets supplemented with 200ppm Diclazuril and 500ppm Salinomycin, respectively. Treatments 3 and 4 were designated as positive and negative control, received no coccidiostate. Chickens in treatment 1, 2 and 3 were inoculated with a suspension containing four Eimeria species. Frequency of excreted oocyst obtained from feces samples during 7-13 days post - challenged was carried out. Body weight, body weight gain, feed conversion ratio and mortality rate were evaluated weekly. The results revealed that coccidiostatic drugs decreased oocyst per gram of feces significantly in 7-13 days post inoculation (p<0.05). The highest mean of body weight was related to negative control followed by chickens treated with Diclazuril. The lowest FCR was belonged to negative control followed by chickens treated with Diclazuril. It could be concluded that coccidiostate -supplemented diets in Eimeria infected groups shed less (P<0.05) oocyst than control-infected chickens and improved production performance in coccidian- infected broiler chicks.