Chaoqun Yao

Chaoqun Yao

Ross University School of Veterinary Medicine St. Kitts West Indies

Title: Bovine trichomoniasis in beef cattle in Wyoming, USA


Dr. Chaoqun Yao completed a MD and PhD from Tongji Medical University and University of Georgia, respectively. He pursued post doctoral training at Washington State University and University of Iowa where he was promoted to Associate Research Scientist. He was a tenure-track Assistant Professor at University of Wyoming with a concomitant appointment of Parasitologist at the Wyoming State Veterinary Laboratory. He is currently an Associate Professor at Ross University School of Veterinary Medicine. He has published more than 45 papers inpeer-reviewed journals and has been serving as an editorial board member and ad hoc reviewer for many journals.


Tritrichomonasfoetus, a trichomonad protozoan residing in the reproductive tract of cattle and the large intestine of the domesticated cat, causes trichomoniasis with very different clinical manifestations among these animals. Bovine trichomoniasis is a venereal disease and has been endemic in the USA since the 1930s. Currently 26 states including Wyoming impose regulations on the disease. The major purpose of the present study was to gauge the disease trend in Wyoming since enforcement of the state rules. A retrospective study was performed to include all accessions between 2000 and 2010with producers’ residency in Wyoming collected by the Wyoming State Veterinary Laboratory and the Wyoming Livestock Board. A questionnaire surveyed all Wyoming beef cattle producers to identify herd-level risk factors. Individual prevalence of T. Foetus in bull populations declined from 1.7% to 0.2%, which was linearly correlated with year (R=0.717, P=0.009). At the same time an accumulative positive rate of 9.7% and 4.5% was found among 93 cows/heifers with a history of abortion and 22 aborted fetuses, respectively. Furthermore, between 2007 and 2010, average herd prevalence was 2.2% with 15 of the 23 counties having at least one positive herd.T. foetus infections were found to be significantly (P0.05) associated with neighbouring positive herd(s), grazing on public allotments and comingling with other herds. Based on these data an integrated approach was developed to control and eventually eliminate bovine trichomoniasis, which is suitable for all herds in which live cover breeding is used regardless of geographic regions.

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