Detection and genetic diversity of Cryptosporidium in yaks in Xinjiang, China.

Cryptosporidium spp. is an important protozoan parasite that can cause diarrhea in both humans and animals worldwide. In the present study, a total of 826 yak fecal samples were collected from six counties in Xinjiang and tested for Cryptosporidium using PCR. Based on the SSU rRNA gene, 20 samples tested positive for Cryptosporidium, resulting in an overall infection rate of 2.4 % (20/826). Hejing County exhibited the highest infection rate at 5.6 % (16/288), with significant ``Cryptosporidium species and one genotype were identified: C. bovis (n = 12), C. parvum (n = 3), C. ryanae (n = 3), C. occultus (n = 1), and Cryptosporidium sp. rat genotype IV (n = 1). Subtyping via the gp60 gene revealed two subtypes for C. bovis (XXVIb, n = 4; XXVIc, n = 4), one subtype for C. ryanae (XXIa, n = 1), and one subtype for C. parvum (IIdA19G1, n = 1). Phylogenetic analysis indicated that these subtypes clustered with reference sequences from other regions and hosts, without distinct geographical or host specific isolation. In conclusion, the prevalence of Cryptosporidium infection in yaks in Xinjiang is low, and the subtypes of Cryptosporidium exhibit genetic diversity among different bovine species.