Trichomoniasis in a dairy herd: Control by artificial insemination and prostaglandin F 2α treatment

Abstract

Trichomoniasis was diagnosed as the cause of first and second trimester abortions in a dairy herd. The original herd sire, a 72-mo-old Holstein bull, was removed 4 mo prior to diagnosis of trichomoniasis. The infection was maintained within the herd and further transmitted by a 24-mo-old Holstein replacement bull during this 4-mo period. Removal of the 24-mo-old bull from the herd and exclusive reliance on artificial insemination with semen approved by Certified Semen Services resolved the infection in this herd, although abortion due to Tritrichomonas fetus continued to occur for 4 mo after removal of the 24-mo-old Holstein sire. Prostaglandin F 2α (25 mg intramuscularly) was administered twice, 10 d apart to four cows with clinical pyometra due to Tritrichomonas fetus in this herd. All four cases were clinically normal when examined 10 d after the second treatment. Three cows were artificially inseminated with Certified Semen Services (CSS) approved semen after treatment. Pyometra recurred in two of these cows. Trichomonads were demonstrated in the uterine fluid of both of these latter cows when pyometra recurred, indicating infection had persisted despite prostaglandin treatment. Prostaglandin F 2α, therefore, can be used to assist in the expulsion of fluid and reestablishment of regular estrous cycles in cases of pyometra due to Tritrichomonas fetus, but genital tract infection with Tritrichomonas fetus can persist despite prostaglandin treatment.