Isolation, Characterization and molecular identification of Eimeria spp. in young calves

In this study, the ITS-1 region of ribosomal RNA genes of six bovine Eimeria species: E. alabamensis, E. auburnensis, E. bovis, E. cylindrica, E. ellipsoidalis and E. zuernii analysed by PCR and the results of molecular methods analysed to find any relationship between presence of parasites and diarretic status. Studies were conducted in calves aged less than 3 months for a period of 2 years. During the study period, 160 dung samples were collected from neonatal calves and examined first microscopically and then by molecular techniques. Stools were analyzed for the presence of Eimeria Spp. oocysts by Sheather's Sugar Flotation Solution method. DNA was extracted and PCR were done to identify six cattle-adapted specie (E.alabamensis, E.auburnensis, E.bovis, E.cylindrica, E.ellipsoidalis and E.zuernii). Eimeria spp. infection was detected in 15 (9.37%) of 160 calves without a history of diarrhea infection and pathogenic Eimeria spp. was asymptomatic in all animals that was not positively related to the diarrheic status of the calves (P>0.05). According to microscopic analsis 6 species (E.alabamensis, E.auburnensis, E.bovis, E.canadensis, E.ellipsoidalis, and E. zuernii) identified and with molecular technique 3 species (E.auburnensis, E.bovis, E. zuernii) were detected. Different risk factors were considered to affect the rate of infection of calves with this protozoan parasite. For controlling disease, Immune status of the calves should be improved by providing sufficient amount of colostrum within the first 24 hours after birth and good hygiene as well as reducing and monitoring stress levels caused by weaning, a change in feed and overcrowding.