Tritrichomonas foetus infections in female beef cattle with abortion in Wyoming, USA

Abstract

Introduction: Bovine trichomoniasis has been endemic in the USA since its discovery in the 1930s. Testing of bulls used for reproduction is currently mandated in 26 states to control spread of the disease. Although individual head prevalence in Wyoming has decreased since 2000 when the state's regulation started, the herd prevalence remains steady and the disease continues to have a wide geographic distribution. One factor neglected in current regulations is the role of infected cows/heifers in transmission. The latter may harbour Tritrichomonas foetus, the causative organism, up to a few weeks post‐abortion/parturition. This capacity enables them to spread the disease in spite of extensive bull testing. Case presentation: The purpose of the present study was to determine the prevalence among Wyoming beef cattle of detectable T. foetus infection in cows/heifers with a history of abortion for which samples had been tested. This retrospective study included all submissions to the Wyoming State Veterinary Laboratory between 2000 and 2010. Cows/heifers with a history of abortion among Wyoming producers were tested for trichomoniasis. Overall prevalence was 9.7 %. Furthermore, 4.5 % of aborted foetuses were positive. Conclusion: Our data collectively demonstrates that a percentage of cows/heifers that recently experienced abortion are positive for T. foetus and may play an important role in maintaining endemicity of bovine trichomoniasis.