Trich Prevention in Bulls
Trichonanias is a protozoan venereal disease that causes abortion in cattle. The article below has a good review of the disease and its management. There is a vaccine registered for use in cows to help suppress the disease, however there is NO vaccine registered for use in bulls.
Control of the disease is by testing all the bulls in the herd for the organism, and eliminating those with the disease. Infected bulls are unlikely to ever clear the disease.
If you are suspicious that there is trich in the herd that you are planning to put the bull in, you may wish to reconsider your decision, to prevent your bull, if he is clean, from picking it up from a "hot cow". Cows which have or contract trich during breeding usually abort the fetus and recycle before they clear the disease, subsequently infecting the next bull that breeds them.
You may also wish to consult your local veterinarian, and or your local Extension Office, which should be be able to locate by searching for "Extension " and the county and state which you live in.
So if I were to vaccinate the bull
1) I could possibly make him sick ?.
2) It would have no effect
3) It could possibly afford him some measure of protection ?
Rgds : Jon Byers
AS you must be aware, trich is a serious production issues in some places. Here in Idaho, bulls must pass a trick inspection before they can be turned out on public range in common with other peoples cattle.
Know the animal pharmaceutical industry, if the vaccine were even a little effective in bulls, and it didn't have any negative effects, I am sure that it would have received registration for use in bulls.
I am pretty sure that the reason that it is ineffective in males is that the protozoa hang out in the puces in the crevices in the penis, etc., where there is no circulation for any antibodies, which might be formed in the blood due to the vaccine, to reach them. By contrast the vagina of the cow is constancy being swept clean by menstrual blood, and there are far fewer crevices for this relatively large organism to hide out.
Testing of your bull(s) and those of the other producers bulls you might run in common with, is really the only way to protect yourself. The vaccine may help in preventing transmission and shedding of the protozoa in cows, and cows can actually clear the protozoa out of the reproductive tract. A history of late calvers is an indication that there may be a problem.
I'm sorry but there doesn't seem to be a "magic bullet" for this problem, and it seems to be spreading around the country where strict enforcement procedures are not in place....Good Luck.