epidemiology of eimeria species in selected broiler farms of khoy suburb, west azarbaijan province, iran

intestinal coccidiosis, caused by eimeria species, is an economically-important disease of poultry production industry worldwide. this study was designed to investigate the prevalence of different eimeria species in the farmed broilers of khoy city, west azarbaijan, north west iran. a total of 26 broiler farms of different production capacities were arbitrarily selected and examined in 2013. in each of the farms, litters of two broilers farms were randomly sampled twice a week and examined. the intensity of infection with each of the eimeria species was assessed on the basis of number of oocysts per gram of litter using clayton-lane and mcmaster methods. eimeria species diversity was determined by using oocyst sporulation technique in 2% potassium dichromate solution. results indicated that 23.08% (6/26) of the broiler farms were infected with eimeria oocysts. the maximum litter infection rate (7.5×103) was observed in fifth week of the rearing period. the litter infection rate was significantly correlated with kinds of water dispenser, feeder, ventilation, and density. the litters were infected with five eimeria species; e. maxima (32.67%) in 6 farms (23.07%), e. mitis (24%) in 6 farms (23.07%), e. acervulina (18%) in 5 farms (19.23%), e. tenella (14.67%) in 4 farms (15.38%), and e. necatrix (10.67%) in 3 farms (11.58%). results of this study uncovered high rates of litter infection with various eimeria species in the studied farms, suggesting the establishment of firm health management strategies in the region.