Potentially exposed bulls include all of the bulls that have been in contact with any cows or bulls from the breeding pasture that contained a test positive animal. If you opted to sell all of these bulls instead of test, then you will not have any potentially exposed bulls.

Potentially exposed cows include any cows that were in a breeding pasture that contained a positive animal. If you chose to keep some cows that did not produce a healthy calf prior to the next breeding season, these cows will be at high risk for having Trich and appropriate management of this group of cows is extremely important to avoid spreading Trich to the rest of the herd.

Potentially exposed cows and bulls should be managed as a separate herd for the next breeding season.  These animals must be permanently identified and appropriate herd records must be kept so that these animals can be identified later in the year (or coming years) and returned to their management group should they happen to get out.    The bulls should be removed from the breeding pasture after 90 days or less and maintained as a separate group from the rest of the bull battery. The cows should be examined for pregnancy in a timely fashion and the bulls should be tested for Trich 1 week after the breeding season to evaluate the success of removing Trich from the herd. 

There is a Trich vaccine on the market that may be of some benefit in reducing the number of abortions if Trich is still in the herd.  The vaccine, however, will not eliminate the disease from your herd.  If you chose to keep any cows that are at high risk for having Trich you may want to consider vaccinating. Please discuss the economics of using this vaccine with your veterinarian.

If the pregnancy rate of this group is acceptable and the Trich tests come back negative then it will no longer be necessary to manage and maintain 2 separate herds.

Alexander et. al., Aus Vet J, 1953. Christensen et. al., Aus Vet J, 1977. Clark et. al., Aus Vet J, 1983. Cobo et. al., Therio, 2007. Gault et. al., Am Vet Res, 1995. Gooder et. al., JAVMA, 1986.  Kvasnicka et. al., Therio, 1989.  Kvasnicka et. al., Am J Vet Res, 1992.  Mancebo et. al., Vet Parasit, 1995.  Schnackel et. al., Ag Pract, 1989.  Skirrow et. al., AM J of Vet Res, 1990. Skirrow et. al., JAVMA, 1987.