Livestock producers treat calves early to keep them healthy. But ensuring a clean bill of health for your herd is not always that easy, especially when sympotms fly under the radar.
A veterinarian speaks to a silent virus, impacting U.S. cattle herds.
Dr. Peggy Thompson, cattle professional services veterinarian for Boehringer Ingelheim, says bovine viral diarrhea virus impacts “all ages of cattle.”
“The main thing it does is suppress the immune system of those cattle,” Thompson said. “That can lead to issues with respiratory disease, or pneumonia in calves. It can also lead to reproductive issues where you can have abortions in your cow herd.”
The biggest issue surrounding BVDV is persistently infected, or PI calves. Dr. Thompson speaks to the development of persistently infected calves, as well as the damage they cause.
“What happens is that cow, when she’s pregnant, gets exposed to the BVDV virus. That virus crosses the placenta and infects the calf,” Thompson said. “Because the calf isn’t completely formed yet, its immune system doesn’t know how to fight off the disease, so that calf can be born persistently infected with the virus. We call them ‘PI calves,’ but what they really are is the ‘Typhoid Mary.’ They’re constantly spreading that BVDV virus to the rest of its herd mates.”
Identifying calves with BVDV proves challenging, as they seem just as healthy as the rest.
“Some clinical signs are non-specific, but anytime you have cattle that are depressed, off feed, (or) showing signs of respiratory disease, BVDV could certainly be a piece of that problem.”
Tomorrow, Dr. Thompson will speak to controlling bovine viral diarrhea virus.