We have all seen the cows that experience extreme inflammation at the time of calving, those with swelling in the udder and beyond. While it is known that extreme and chronic inflammation can suppress milk production and reduce reproductive efficiency, should we eliminate all inflammation at calving if we could?
According to Michigan State University’s Barry Bradford, the answer to that question would be no. That’s because inflammation plays an important role in the birthing process.
“Inflammation is necessary in three ways for birthing to happen normally,” he said during the September Hoard’s Dairyman webinar. The first, he said, is to stimulate the release of proteases that break down the connective tissue that leads to the loosening of the cervix and allows for normal birthing to occur.
The second purpose is that inflammation sends signals that stimulate the muscle cells in the uterus to contract. This leads to the contractions needed for delivery.
Lastly, inflammation stimulates the synthesis of prostaglandin, which is an important hormone during the birthing process.
Bradford pointed to a large Canadian study that highlighted the importance of inflammation at calving. Since inflammation can cause increased body temperature and depressed feed intake in post-fresh cows, researchers at the University of Guelph wondered if administering an anti-inflammatory drug around calving would help cows feel better and, therefore, visit the feedbunk more.
More than 1,300 cows were administered Banamine at two hours and 24 hours post-calving. Instead of seeing a positive response, cows that received treatment had a 2.5 fold increase in retained placentas and a 50% higher rate of clinical metritis. What’s more, the original study called for the first dose of Banamine to be administered 24 hours prior to calving, but that research had to be halted due to a dramatic rise in stillborn calves.
Bradford said this study and others in literature show evidence that blocking inflammation the day of calving can interfere with inflammatory signals needed for delivery and expelling the placenta.
So, while preventing inflammation at calving may yield negative results, Bradford said the resolution of inflammation is key to helping keep it in balance. Cows that rapidly resolve inflammation after calving go on to have better metabolic health and normal estrus cycles. Those that experience a slow resolution face negative energy balance, metabolic disease, and infertility.