Dominance of Enterocytozoon bieneusi genotype J in dairy calves in Xinjiang, Northwest China.

Enterocytozoon bieneusi is the most common microsporidia species in humans and has a variety of animal hosts. To assess the prevalence and molecular characteristics of E. bieneusi in dairy calves in the Xinjiang Uyghur Autonomous Region of China, 514 fecal samples were collected from 15 farms and examined by polymerase chain reaction based on the internal transcribed spacer of the ribosomal RNA gene of E. bieneusi. The overall prevalence of E. bieneusi in calves was 16.5% (85/514). No significant difference in prevalence was observed between pre- and post-weaned calves. Sequence analysis of ITS nucleotide sequences identified six known genotypes (BEB4, CC4, D, I, J, and EbpC), five of these previously detected in humans. Genotype J was the most prevalent genotype (57/85) and was identified on 11 farms. The high prevalence of zoonotic E. bieneusi genotypes in dairy calves suggests they are a potential source of zoonotic infection in humans. Copyright Â