Molecular identification of Cryptosporidium spp. and Giardia duodenalis in grazing horses from Xinjiang, China.

A total of 262 fecal specimens collected from grazing horses at five locations in Xinjiang, China were examined by PCR for Cryptosporidium spp. and Giardia duodenalis. The Cryptosporidium and G. duodenalis infection rates were 2.7% and 1.5%, respectively. Seven Cryptosporidium-positive specimens were found in foals (16.3%), and four G. duodenalis-positive specimens were found in mares (2.5%). Sequence analyses of 18S rRNA and gp60 genes revealed that seven animals were positive for the subtype VIaA15G4 of Cryptosporidium horse genotype. G. duodenalis assemblages A and B were identified by molecular characterization of the 16S rRNA and tpi genes. This is the first report of Cryptosporidium horse genotype and G. duodenalis in grazing horses from China.