Just when you thought it was safe to go back in the water

News
Jun 4, 2010
by WLJ

Several generations of Oklahoma cattlemen have grown up with the fact that their breeding stock were going to need to be Bang’s tested at the sale barn or when changing ownership. In 2009, however, this fact of life came to an end; no more sale barn testing for brucellosis. Now we find ourselves, before the celebrations have even died down, looking at another emerging reproductive disease problem of cattle that may once again require testing of breeding stock when they change ownership. Trichomoniasis (commonly called trich) is the new bad guy.

Trichomoniasis is a protozoal disease that is spread among cow herds by venereal contact. It shows up as various infertility problems, including open cows, late calves, abortions, and uterine infections. If given sufficient time, the cow will often develop sufficient immunity to conceive and carry a calf to term. The immunity is short-lived, however, and if exposed to an infected bull again next year, the problem repeats itself. One bull can infect a few cows, which infect several bulls, which infect many more cows. If undetected, the problem is usually much worse in the second year.

The bulls are carriers of the disease and most bulls, especially those over two or three years of age, are carriers for life. The only way to stop them from spreading the disease through your cows is to send them to slaughter.

There are two commonly employed tests for trich. The culture method consists of obtaining a wash of cells and debris from the sheath of the bull, which is then submitted to the diagnostic lab for culture. It is easy and relatively inexpensive, but not very reliable. To be considered a negative test, a series of three cultures must be obtained from the bull over time and all deemed negative. Its main value is as an unofficial screening test for detecting the presence of the disease in a herd that has multiple bulls. The Polymerase Chain Reaction test is much more accurate, although more expensive. It will definitively confirm or deny the presence of the organism in an individual bull and only one test is needed.

Trich is not a new disease, but rather one that is becoming much more common.

Easier movement of bulls, leasing bulls, and purchasing non-virgin bulls all have led to an increase in your chances of bringing this problem home with you. Oklahoma currently has regulations for bulls being brought in from out of state. The legislature is also considering new regulations that would require testing whenever Oklahoma bulls change hands. This is a disease we will be hearing much more about in the months to come, so take advantage of opportunities to educate yourself.

No one knows just how big a problem this is in Oklahoma at this time, but if your herd’s number comes up in the disease lottery, it will be a very big problem for you. When Texas started mandatory testing of bulls whenever they changed ownership, they found about a 3 percent rate of positive tests, and most authorities expect the numbers to be similar in Oklahoma. Dr. Rod Hall of the Oklahoma Department of Agriculture, Food, and Forestry, estimates that Oklahoma stockmen are currently losing about $5.4 million annually to trich. Trich is a bad dude with fast hands. Learn what you can do to keep those hands out of your pocket. — Dave Sparks, DVM, Oklahoma State University Area Extension Food Animal Quality and Health Specialist

{rating_box}