Prevalence of subclinical coccidiosis in river buffalo calves of southwest of Iran.

Despite the importance of buffalo farming in Iran, little is known in this country about the abundance and distribution of Eimeria spp. in the animal species. The present study was designed to investigate the prevalence and species characterization of Eimeria oocysts in river buffalo calves of Khuzestan province, southwest of Iran. Of the total 108 fecal samples examined for Eimeria, 108 (100%) were found infected with 11 species of the parasite. Among the identified species of Eimeria, E. bovis was found to be the predominant etiological agent (76.85%), followed in order by E. canadensis (62.96%), E. zuernii (47.2%), E. ellipsoidalis (26.85%), E. subspherica (25.92%), E. brasiliensis (19.4%), E. auburnensis (18.51%), E. alabamensis (14.81%), E. pellita (11.1%), E. illinoisensis (5.5%) and E. bukidnonensis (2.7%). In most calves multiple infections with three species were present. While, 20.7% of calves showed heavy infection, 50.4 and 24.8% of calves showed weak and moderate infection, respectively. There was no significant difference in the OPG values between the calves of different localities. There was also no significant difference between the prevalence rate of infection in males and females. A total of 16.6% of all faecal samples were found to be diarrheic. A highly significant relationship could be identified between the occurrence of diarrhea and the level of E. bovis and E. zuernii oocysts excretion. Considering the pervasive occurrence and negative effects of the infection on the health condition and the growth performance of buffalo calves, infections should receive increased attention by both farmers and veterinarians.