Source: Midwestern Cattle Marketing, LLC
One reproductive disease that all cattle ranchers find disastrous to a cowherd is Bovine Trichomoniasis also known as Trich.
Bovine Trichomoniasis is a veneral disease caused by the protozoan Tritrichomonas foetus, a mobile complex, single-celled organism that is characterized by the early embryonic death of a fetus.
The primary production and economic impact of Trich is on the cows and heifers in the herd.
This is because the disease causes infertility and abortions. And to some ranchers dismay it can extend the breeding and calving season on the ranch.
Trich will not have any visible symptoms in bulls and rarely any in cows and heifers.
“Because the organism lives in the female reproductive tract, it’s very difficult to collect samples from cows,” says John Wenzel, New Mexico State University Extension DVM. “In bulls, the organism lives on the penis surface, making collection and sampling easier.”
Bulls become infected by breeding infected cows and when a bull becomes chronically infected, he never clears the disease. Some state regulations require the slaughter of infected bulls.
Labatory tests can determine whether a bull is infected. Only a certified, accredited veterinarian may collect samples from the bull’s penis and internal prepuce and submit them to a certified lab.
There are two tests that veterinarians can be give to test bulls. Real Time-Polymerase Chain Reaction (RT-PCR) and a culture test.
“Cows and heifers become infected when bred by an infected bull, but can later clear the disease and return to normal estrus,” states Wenzel.
The protozoa can reside in the vagina, cervix, uterus, placenta and even the fetus.
The organism causes the cow or heifer to abort the fetus in the first 60 days of pregnancy.
After the cow returns to normal estrus, she’ll usually clear the infection in 3 to 5 heat cycles, so she will need around 120 to 150 days of sexual rest to make sure she clears the infection.
Cows can acquire temporary immunity for up to 15 months. However, this immunity is shortlived and a cow can be re-infected. To help reduce the severity of the disease in an infected cowherd, ranchers can vaccinate the cows.
Repeat breeding, extended calving season, very early abortion, high percentage of open cows at pregnancy check are all signs that Bovine Trichomoniasis is on your ranch.
To prevent Bovine Trichomoniasis on your cattle ranch maintain a closed herd by separating breeding groups, test all new bulls that enter the herd, as well as before breeding the season and try to use young herd bulls or use tested virgin bulls.
Trich Truths:
· Bovine Trichomoniasis does not affect semen quality of semen behavior.
· Bulls are asymptomatic carriers of Bovine Trichomoniasis.
· Bulls infected with Bovine Trichomoniasis serve as a reservoir of infections in a cowherd.
· Bovine Trichomoniasis can only be transmitted by sexual intercourse and not by the environment.
· Bovine Trichomoniasis is not transmitted to humans.
Remember to check with your state’s Bovine Trichomoniasis regulations for testing and procedures.
Most regulations only impact bulls, but there are regulations and tests for positively tested bulls, untested virgin bulls, and untested non-virgin bull.
Callie’s Prevent Trich Tip: Don’t forget to test your bulls before you turn them out on cows!
Callie McCullough is a junior at Texas A&M University pursuing a dual degree in animal science and agricultural communications. She’s a fifth generation rancher from Ridge, Texas. Born and raised on the family cow-calf operation, she is an avid cattle enthusiast and has a passion for the production cattle industry and its future. cmccullough@tamu.edu
