January 2008
From the State Vet's Office

A Rising Tide Raises All Ships

by Dr. Tony Frazier

Early in 2007, the Alabama Voluntary BVDV Control Program rolled off the assembly line. The program was the result of a tremendous amount of work done by numerous groups in the state involved in veterinary medicine and the cattle industry. The majority of the work was done by Alabama Extension Veterinarian, Dr. Soren Rodning. Because of the losses that occurred, especially in feedlot, due to the Bovine Viral Diarrhea Virus (BVDV), the group addressed not only what could be done to reduce these feedlot losses, but also how Alabama could lead the way in confronting this problem. The question to be answered was, "How can we in Alabama offer calves to feedlots that are certified not to be persistently infected with the Bovine Viral Diarrhea Virus?" The Voluntary BVDV Control Program answers that question and allows anyone who wishes to participate in it to take advantage of it.

Before going into detail about the program, a little background on BVDV and persistently infected (PI) cattle is needed. The disease is manifest in various ways, with one aspect in common. It literally wreaks havoc on the immune system. Beyond that, it may cause erosions on some or all mucous membrane surfaces, as well as causing lesions all through the intestinal tract. The lesions in the intestine result in inappetence, dehydration and, of course, diarrhea. The real problem in feedlot cattle, however, is the persistently infected calves. Those calves are infected in the uterus during the first four months of development. If exposed during that period, the calf’s immune system will never recognize the virus as the enemy and will not mount an immune response. Many of these calves either die and are aborted, or they are born weak and die very young. There are a few of these calves infected in the uterus prior to four months of development that do not show signs of illness, but continually shed large amounts of the virus. In the feedlot environment where a group of calves are constantly in close proximity in their feed pen, a PI can cause tremendous problems. Even though the other calves in the pen with the PI calf may have been vaccinated for BVDV, the constant exposure to high levels of the virus being shed by the PI calf forces the pen mates’ immune systems to continuously work at full capacity. The chronic exposure will eventually take a physical toll on those animals. That toll may be either through loss of production, illness or both. The letters PI around a feedlot are certainly a four-letter word.

The Voluntary BVDV Control Program offers producers the opportunity to have their calves tested, so buyers may be assured there are no PIs in the group. This aspect is especially attractive to producers who sell calves in group lots going to be kept together in a feedlot pen. To me, the most attractive aspect of the program is the ability to certify one’s breeding herd as PI free. If a cow in the brood herd is infected with BVDV, she will produce PI calves. Through testing the herd, any of these brood cows can be identified and eliminated from the herd. The certification aspect of the program should be especially attractive to those selling seed stock. Anyone who has ever had BVDV go through their herd, or who have had a PI animal in their herd, will recognize the advantage of purchasing their replacements and bulls from a PI free herd.

During the past year, people from across the United States have been very interested in the Alabama program and how it will work. Dr. Rodning has been asked by many groups across the country to give presentations about the program. As I travel to meetings involved in the national cattle industry and government leadership, I am often asked how the BVDV program is going. There is interest nationally about if our program goes well, so others may follow. There are a few other states also in the developing process of BVDV control programs. It would be a major benefit to the beef industry for these programs to get off the ground and be successful. I have a friend who grows stockers out in Colorado. He gets most of his calves out of the Southeast. He once told me if the Alabama BVDV Control Program gets up and going well, it should have a positive effect on all Alabama calves. I asked him why he thought it would even affect the price of calves not in the program. He just smiled and replied, "A rising tide raises all ships."

If you have any questions about the Alabama Voluntary BVDV Control Program, do not hesitate to give us a call at 334-240-7253. We will put you in touch with Dr. Rodning.