study on frequency and diversity of eimeria species in broiler farms of hamedan suburb, iran

background: coccidian infection in poultry is the most common infection in the world and is the cause of mortality and great economic losses in poultry production. objectives: this study was aimed to determine the frequency and eimeria species diversity in broiler farms of hamadan suburb, iran. methods: a total of 16 broiler farms were randomly selected with different production age in 2012. the information about poultry production and hygienic management of the farms was recorded. during the course of the study, litter sampling was carried out two times per week for each two farms with the same production status. the litter samples were subjected to flotation technique for collecting eimeria oocysts. the intensity of infection was determined on the basis of oocyst per gram of litter (opg) using clayton-lane and mcmater methods. eimeria species diversity and frequency was also determined by using oocyst sporulation in 2.5% potassium dichromate and micrometry. results: a total of 12 (75%) broiler-chicken litters were positive for eimeria oocysts. the intensity was significantly variable in the farms ranged from 2.2×102 and 1.45×105. according to laboratory identification, four eimeria species were detected in litter of all infected farms. the species frequency was e. tenella in 11 farms (69%), e. maxima in 10 farms (62.5%), e. acervulina in 8 farms (50%), and e. necatrix in 7 farms (44%). conclusions: the frequency and eimeria species diversity in litter of industrial broiler-chicken of hamadan suburb indicated a need to improve the hygiene and management principals of the farms in the region.