Bovine Trichomoniasis Diagnosis
Information about how the disease is diagnosed.
Because infection is inapparent in bulls and mild vaginitis is found only occasionally in cows, a definitive diagnosis requires the identification of parasites in infected animals.
T. foetus is best located in preputial or vaginal secretions and, to a lesser extent, amniotic, allantoic, or abomasal fluids from the infrequently aborted fetuses. Direct microscopic examination of these fluids can be performed. More commonly, samples are inoculated into one of the several media, most notably Diamond’s or Claussen’s media, and allowed to grow in vitro until sufficient numbers of parasites are present to allow detection by light microscopy.
In bulls, the organisms are in the prepuce, frequently in small numbers. Microscopic examination of preputial smegma for trichomonads is the most common method to confirm a herd diagnosis. Culturing increases sensitivity markedly over direct exam. However, even with culturing, there is a 10-20% probability than an infected bull will be missed by a single culture; hence, multiple cultures are recommended.
