Trichomoniasis
Bovine trichomoniasis, or "trich", is a sexually transmitted disease of cattle caused by the parasite Tritrichomonas foetus. Trich causes abortions and reduced fertility in cows and can be financially devastating to a cattle herd by reducing pregnancy rate, reducing the calf crop, and spreading out the calving season, resulting in fewer and lighter-weight calves at weaning. The Utah Department of Agriculture and Food (UDAF), in cooperation with the Utah Cattlemen’s Association, veterinarians, and cattle producers, has implemented a strict trich control program to protect our cattle industry from this disease.
The Disease
Tritrichomonas foetus is a parasite that is spread during breeding. Cows tend to clear the infection within 120 days, but the parasite lives in the folds inside the prepuce of bulls and is never cleared. There is no treatment for trich, and vaccines just reduce the length of time cows are infected. Infection in cows causes abortions in the first 3 months of pregnancy. A herd outbreak can lead to severely low pregnancy rates, an increase in the number of short bred cows, and infections of the uterus, called pyometras.
Testing
Veterinarians certified by UDAF collect a sample from inside the bull’s prepuce (the sheath surrounding the penis). That sample is placed in a tube containing special media, and the tube is sent to a diagnostic laboratory. The lab runs a PCR test, which looks for trich genetic material. At the time of the test, the veterinarian will place a trich tag corresponding to the year of testing and an RFID tag. The RFID tag allows UDAF to look at the bull’s test results from previous years if one tests positive. The RFID tag also allows bull owners to prove that the bull has been tested if the trich tag falls out.
Positive Herd Management
If a bull tests positive for trich, UDAF is notified, and the State Veterinarian will quarantine the herd until they are satisfied that there is no more trich in the herd.
- The owner must notify all neighbors with fence line contact and administrators of common grazing allotments. They must also provide a list of all neighbors and herds in common grazing allotments to UDAF.
- Positive bulls must go to slaughter within 14 days.
- All other bulls need one additional negative test before they can be placed with cows.
- Cows and heifers over 12 months old are quarantined unless they have:
- No exposure to bulls since calving
- Are at least 120 days pregnant
- Haven’t had exposure to bulls in 120 days
Utah Rules
Resident Bulls
- Test every bull, every year (except dairy bulls in confinement and bison bulls) between 10/1 and 5/15 and before female exposure
- Re-test before sale/lease/transfer if female exposure
- Bulls that stray are required to be tested at the owner’s expense
Imported Bulls
- Every bull over 12 months of age must be tested within 30 days of import
- Rodeo/Show bulls coming in for one show/ rodeo are exempt
- Bulls on commuter permits must test within the previous 12 months
Positive Herd Management
- Have good perimeter fences
- Know who you are grazing with. Only graze in associations that require all bulls to be tested before entry
- Use younger bulls
- Test all bulls before adding them to your herd
- Don’t buy open or short-bred cows
- Use artificial insemination
- Avoid year-round breeding