Prevalence of Trichomoniasis in Alabama Beef Bulls

Abstract

Bovine trichomoniasis is a venereal disease caused by the protozoan Tritrichomonas foetus. Trichomoniasis is a major cause of fetal wastage throughout the world, and it causes substantial economic losses wherever natural breeding conditions exist. Several estimates are available regarding the prevalence of trichomoniasis in different regions of the United States and throughout the world. However, prior to this investigation, no estimates were available regarding the prevalence of trichomoniasis in Alabama beef cattle. Therefore, both a prospective survey and a retrospective analysis were conducted to estimate the prevalence of T. foetus in Alabama beef bulls. The prospective survey included 240 Alabama beef bulls that were sampled between January 2005 and March 2006. Preputial smegma was collected from the 240 bulls with a dry pipette and cultured in an InPouchä TF Tritrichomonas foetus culture pouch (BioMed Diagnostics; White City, OR). The samples were evaluated microscopically once a day for six days for growth of any organism resembling T. foetus. To avoid false-positives due to fecal trichomonads, all suspect cultures were sent to both the Alabama State Diagnostic Laboratory and the Parasitology Laboratory at the Auburn University College of Veterinary Medicine for molecular-based confirmatory assays. Of the 240 bulls cultured in the prospective survey, three cultures (1.25 %) were considered suspect on microscopic evaluation. However, molecular-based assays were negative for T. foetus, suggesting that the samples most likely contained fecal trichomonads. The retrospective analysis included 374 T. foetus cultures performed at the Alabama State Diagnostic Laboratory between October 2002 and March 2005. Of the 374 bulls included in the retrospective analysis, one bull (0.27 %) was confirmed positive by a molecular-based assay. Combining the 240 bulls from the prospective survey with the 374 bulls from the retrospective analysis gave an overall prevalence of 0.16 % (1/614) from October 2002 through March 2006. A prevalence of 0.16 % is lower than expected, but it does indicate the presence of T. foetus in Alabama cattle. Alabama cattle producers and veterinarians should therefore work together to minimize the spread of trichomoniasis throughout the state, including testing for trichomoniasis when dealing with herd infertility problems. Also, despite the low prevalence of T. foetus in Alabama, producers should consider testing all new bulls because of the serious consequences of adding a positive animal to a herd.