CALGARY – A trichomoniasis outbreak in southern Alberta has resulted in one Cardston herd recording only a 30 percent pregnancy rate.
The owner, who was not identified, has decided to feed those cows that aren’t pregnant for slaughter, said veterinarian Andrew Strang of the Foothills Veterinary Clinic at Cardston. The bulls from the herd will also be destroyed and the pregnant cows will be retained even though many will not calve until summer.
The producer had about 300 breeding cows, but as the infertility problems increased during the last few years, his herd decreased, said Strang.
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Following pregnancy checks this fall, another producer noticed about 30 percent of his cows weren’t pregnant because of the trichomoniasis infection, said Strang.
He suspects trichomoniasis has been in the Cardston area for about 10 years but by culling all non-pregnant cows each season, producers controlled infertility. Trichomoniasis is a venereal disease that’s transmitted during breeding from bull to cow and vice versa.
The infection, carried in the sheath of the penis, can spread through an entire herd with no outward symptoms until a high proportion of breeding cows are diagnosed as not pregnant in the fall.
The infection can remain in the cow’s vagina or uterus for several months. Fetuses are either aborted or absorbed early because a placenta can’t develop and attach itself to the uterine wall.
A vaccine is available, but to be effective, owners must combine it with pregnancy checking and cull those with fertility problems.
In northeastern Alberta this fall, seven bulls tested positive for trichomoniasis in three of five grazing reserves. Guidelines are being written for animals entering the pastures for the spring of 1995, said Gerry Ehlert, provincial grazing reserve manager in St. Paul.
“Farmers need to know it’s preventable when you do the proper testing and culling,” Ehlert said.
