– Dr. Michelle Arnold, UK Veterinary Diagnostic Laboratory
Graphic reprinted from https://www.bi-vetmedica.com/species/cattle/products/TrichGuard.html#trichonomics
“Reproductive failure” is an all-encompassing term if a cow loses a calf during pregnancy or if she fails to get pregnant. Causes of reproductive failure are frequently divided into infectious and non-infectious categories. Examples of “non-infectious” include poor cow nutrition (lack of energy and micronutrients such as selenium/Vitamin E); bull infertility, disease and injury; breeding season management errors (shortened breeding season, insufficient bull-to-cow ratios); genetic and some congenital abnormalities that result in fetal death; and toxic agents such as nitrates, phytoestrogens, and drugs including steroids and prostaglandins. “Infectious” causes are bacteria, viruses, protozoal and fungal agents that directly or indirectly damage the placenta and/or the fetus. Examples include the BVD virus, IBR virus, the protozoan Neospora caninum, the bacterium Leptospira, and the venereal diseases trichomoniasis and vibriosis, among many others. This series of articles will explore the most common infectious causes of abortion and reproductive failure in cattle and available options for control and prevention.
The most common venereal diseases of cattle are trichomoniasis and vibriosis, often referred to as “trich” and “vibrio”, respectively. Bovine trichomoniasis is caused by the protozoan Tritrichomonas foetus (T. foetus) while vibriosis is caused by the bacterium Campylobacter fetus subsp. venerealis (C. fetus) Although both are infrequently diagnosed, the results of infection on reproduction can be devastating. Both trich and vibrio are transmitted through physical contact when a bull breeds a cow. Once a cow is infected, she acts as a source of infection for other non-infected bulls within the herd which then spread disease to other cows. Infected bulls show no signs of disease, however, either pathogen in cows causes genital infection characterized by early abortions, low pregnancy rates, and prolonged calving seasons. In herds that do not check females for pregnancy, these diseases appear simply as cows coming up open that should Continue reading Bovine Venereal Diseases – Should You be Concerned? →