Bovine trichomoniasis (Trich) is a sexually transmitted disease caused by Tritrichomonas foetus (T. foetus). The disease causes infertility, abortions and delayed calving in cows and heifers. Trich is caused by a motile, complex, three-haired, single cell organism (protozoa). It survives in the microscopic folds of the bull’s penis and internal sheath and colonizes in the vagina, cervix, and oviducts in cows. Bulls spread trichomoniasis from cow to cow during natural service. Hence, it can be economically devastating to a herd.
Signs in the herd can include:
- Repeat breedings
- Extended calving season
- Early abortions
- High percentage of open cows
- Pyometra (pus-filled) uterus in a low percentage of cows
The cow, once infected during breeding, does not appear ill, but may show a subtle vaginal discharge 1 to 3 weeks later. However, the protozoa attach to the lining of the reproductive tract and the resulting inflammatory process kills the embryo. In the cow or heifer, the organism lives in the vagina and uterus until her immune system eventually destroys it. Immunity develops after several months but is short lived, so a cow or heifer can become infected again with subsequent breeding.
There are no visible signs in the bull, nor will “trich” affect his sexual behavior. These asymptomatic carrier bulls cause infertility in cows and heifers. The organism lives in the folds of the penis and inside the sheath. As the bull ages, the skin folds increase and deepen in the penis and sheath, creating additional places for the organism to thrive. Therefore, older bulls (over 3 years) are more likely to become chronically infected than younger bulls.
Preventative measures include:
- Use virgin or tested bulls
- Maintain 'closed' herds
- Avoid purchasing open or first trimester bred cows
- Maintain and keep adequate fences
- Keep a short breeding season
Current diagnostic methods for bovine trichomoniasis include microscopic examination of incubated pouches (culture), conventional PCR on clinical samples, conventional PCR in combination with enrichment culture, and real-time PCR performed on enrichment culture. A recent assay developed involves collecting smegma samples in sterile phosphate buffered saline (PBS) and subsequent amplification of rRNA targets for direct reverse transcription quantitative real-time PCR (direct-qPCR).
Frequently Asked Questions about Bovine Trichomoniasis (Trich)
Trichomoniasis Import Regulations
Trichomoniasis Reporting Statute - Miscellaneous Animal Health Statutes (81-202, 54-2945)
Trichomoniasis Neighbor Notification Reporting Form
Trichomoniasis and Your Herd Brochure
Trichomoniasis Presentation:
