Epidemiological Exploration of Cryptosporidium spp., Giardia intestinalis, Enterocytozoon bieneusi, and Blastocystis spp. in Yaks: Investigating Ecological and Zoonotic Dynamics in Lhasa, Xizang

The yak (<i>Bos grunniens</i>), prevalent at an altitude between 3000 and 5000 m above sea level, provides the local inhabitants with meat, milk, leather, fuel (dung), and transport. However, intestinal zoonotic parasites seriously endanger its holistic well-being. The prime concern of this study is to investigate the prevalence of four globally ubiquitous zoonotic enteric protozoans, namely <i>Cryptosporidium</i> spp., <i>G. intestinalis</i>, <i>Blastocystis</i> spp., and <i>E. bieneusi</i> in yaks from different areas of Lhasa, Xizang. In the given study, 377 yak fecal samples from various regions in Lhasa were obtained, including 161 samples from Linzhou County, 66 samples from Dangxiong County, and 150 samples from the Nimu County cattle farms. Molecular identification of these protozoans was done after amplification using PCR and sequencing of PCR-positive samples, and further phylogenetic analysis was performed. The results indicated that the prevalence of <i>Cryptosporidium</i> spp., <i>G. intestinalis</i>, <i>E. bieneusi</i>, and <i>Blastocystis</i> spp. in yak farms in Linzhou County was 48.5, 22.9, 47.8, and 90.7%; 65.2, 13.6, 72.7, and 87.9% in Dangxiong County; and 56.0, 29.3, 58.0, and 80.0%, respectively, in Nimu County. The results of this study provide a basic reference for preventing and controlling intestinal parasites in yaks in Lhasa, Xizang.