Prevalence of coccidial infection in dairy cattle in Shanghai, China

The prevalence of coccidial infections in dairy cattle was examined in Shanghai from November 2010 to March 2011. In total, 626 fecal samples from 24 dairy farms were examined; oocysts were identified to the species level based on morphological features. All herds were infected with Eimeria species. The overall prevalence of coccidia was 47.1%, with the highest prevalence in4-mo-old calves (51.8%) and the lowest in12-mo-old cattle (27.0%). The number of oocysts per gram of feces was significantly higher in young calves than in weaners and adults. Ten species of Eimeria were identified, among which Eimeria ellipsoidalis, Eimeria bovis, Eimeria zuernii, and Eimeria alabamensis were the predominant species. Concurrent infection with 2-8 species was common.