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

<i>Cryptosporidium</i> 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 <i>Cryptosporidium</i> using PCR. Based on the <i>SSU</i> rRNA gene, 20 samples tested positive for <i>Cryptosporidium</i>, 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 ``<i>Cryptosporidium</i> species and one genotype were identified: <i>C. bovis</i> (<i>n</i> = 12), <i>C. parvum</i> (<i>n</i> = 3), <i>C. ryanae</i> (n = 3), <i>C. occultus</i> (n = 1), and <i>Cryptosporidium</i> sp. rat genotype IV (n = 1). Subtyping via the <i>gp60</i> gene revealed two subtypes for <i>C. bovis</i> (XXVIb, <i>n</i> = 4; XXVIc, n = 4), one subtype for <i>C. ryanae</i> (XXIa, n = 1), and one subtype for <i>C. parvum</i> (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 <i>Cryptosporidium</i> infection in yaks in Xinjiang is low, and the subtypes of <i>Cryptosporidium</i> exhibit genetic diversity among different bovine species.