title: Prevalence of Eimeria infection in yaks on the Qinghai-Tibet Plateau of China.
abstract: Few data are available on the prevalence of Eimeria spp. in yaks. An observational study was conducted to determine the prevalence of coccidial infection in yaks on the Qinghai-Tibet Plateau of China. A total of 324 fecal samples from 4 counties was examined, and oocysts were identified to the species level on the basis of morphological features. Eimeria oocysts were found in 113 (34.9%) samples. The species detected and their prevalence values included the following: Eimeria zuernii (54.9%), E. pellita (35.4%), E. canadensis (33.6%), E. bovis (23.0%), E. cylindrica (16.8%), E. subspherica (16.8%), E. ellipsoidalis (14.1%), E. brasiliensis (13.3%), E. wyomingensis (8.0%), E. alabamensis (7.1%), E. illinoisensis (5.3%), E. auburnensis (4.4%), E. bombayansis (3.5%), and E. bukidnonensis (2.7%). Mixed infections of 2 to 7 species were found in 66.4% of the animals. There was an age-related difference in the prevalence of infection. The highest prevalence (53.3%) was observed in calves, an intermediate prevalence in yearlings (36.1%), and the lowest was in adults (15.6%). The number of oocysts per g of feces was significantly higher in calves than in adults. More Eimeria species were indentified in calves. Eimeria zuernii was the most prevalent species in calves and adults, whereas in yearling yaks E. pellita was most common. The majority of calves and yearlings showed mixed infection, but adults tended to be infected with 1 species. The prevalence and intensity of Eimeria species were found to show statistically significant differences among different regions in Qinghai Province.
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai, 200241, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Dong
authors.forename: Chunhua
authors.initials: C
authors.lastname: Li
authors.forename: Qiping
authors.initials: Q
authors.lastname: Zhao
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Hongyu
authors.initials: H
authors.lastname: Han
authors.forename: Lianlian
authors.initials: L
authors.lastname: Jiang
authors.forename: Shunhai
authors.initials: S
authors.lastname: Zhu
authors.forename: Ting
authors.initials: T
authors.lastname: Li
authors.forename: Chunlin
authors.initials: C
authors.lastname: Kong
authors.forename: Bing
authors.initials: B
authors.lastname: Huang
authors.forename: Jinzhong
authors.initials: J
authors.lastname: Cai
mesh_terms: D000367:Age Factors; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000469:parasitology; D002681:China / Q000453:epidemiology; D003048:Coccidiosis / Q000453:epidemiology / Q000662:veterinary*; D004539:Eimeria / Q000145:classification / Q000302:isolation & purification*; D005243:Feces / Q000469:parasitology; D033661:Oocysts / Q000145:classification; D010270:Parasite Egg Count / Q000662:veterinary; D015995:Prevalence