This is probably one of the grosser things I’ve pulled out of a cows vagina. I am sure you’re wondering why it looks this way. Well, unfortunately, I can’t tell you the exact cause (etiology) of why this calf died. BUT, I can tell you a bit about why this calf looks this way and about spontaneous abortions in cattle.
WHAT IS UP WITH THAT CALF? This fetus was extremely smelly, rotten and bloated (which is probably not surprising based on the pictures). This is because the calf probably died prior to labour and had time to ‘cook’ at the moms body temperature before I pulled it out. A bacterial infection could have been the cause of the abortion but it could have contaminated and proliferated in the uterus after the fetus died. We may have been able to get a bit more information about the cause of death if we sent the fetus and placenta away for analysis but the fetus/fetal membranes may have been too autolyzed.
BUT, WHY DID IT DIE? Identifying what cause the abortions is actually quite difficult in livestock. If it is a sporadic case, that is non-infectious there is a low chance that a vet (or histopathologists) will be able to diagnose the cause. If it is an outbreak situation (more than a couple abortions in a herd) and an infectious cause, there is definitely a higher chance of figuring out the ‘why’. This particular case was a random abortion in a herd of 200 cows so a definite diagnosis was not made.
WHAT CAUSES ABORTIONS IN COWS? This is actually a very large list and that is why it can be so difficult to identify the cause of abortions. - Bacterial diseases (Brucella abortus, actinomyces pyogenes, Leptospirosis, etc) - Sexually transmitted or venereal infections (Trichomonas foetus, Campylobacter fetus ss. venerealis) - Viral diseases (BVDv, IBR) - Protozoal infection (Neospora caninum) - Genetic abnormalities - Heat stress (or other physical stressors) - Chemical contaminants or toxic plants in feed (pine needles, poison hemlock) - Mold in feed (mycotoxins, ergot)
It is normal to see about 1% abortions in a herd. Considering the size of this list, it is amazing that we do not see more abortions in cows. This is because farmers are passionate about what they do and care about their livestock. Farmers ensure cattle are vaccinated and dewormed to present diseases, many will introduce “virgin” bulls into their herd to decrease the risk of sexually transmitted infections, cattle are treated when clinical signs of disease appear, and many produces test their feed to guarantee it is safe for their livestock.