Update on Trichomoniasis

In recent years diagnostic surveillance for bovine trichomoniasis has increased since most states require testing prior to interstate movement of non-virgin bulls. However, bovine trichomoniasis continues to be an economically significant disease, particularly in beef cattle, in much of the United States. The disease produces no clinical signs in bulls but can have devastating reproductive consequences on females resulting in reduced calf crops and extended calving seasons. The organism is efficiently transmitted via the venereal route. Although prevalence may be highest in older bulls it has been documented to occur in non-virgin bulls of any age. Bulls are believed to be persistently infected but females develop short lived immunity and naturally clear the infection within 3-22 months. Diagnosis is made by culture in selective media and/or by PCR identification of the organism in smegma samples collected by preputial scraping. Samples of reproductive or fetal fluids obtained from females can also be tested. Readers should consult their state veterinary diagnostic labs for instructions on sample preparation and shipment. Control of trichomoniasis is primarily through testing and culling of positive bulls. There are no approved, effective treatments available. However, vaccination of females will, in most cases, improve reproductive indices in infected herds.