By Jerry Woodruff, DVM
Poor quality forage and less than desirable water sources have put more stress than normal on the cow herd in 2012. As we enter 2013, hoping to be blessed with adequate moisture, we need to focus on the cow herd and protecting the future calf crop.
For a spring-calving herd, we are entering the critical final trimester. The fetus makes nearly 70% of its growth in the last three months of gestation, so meeting the cow’s energy and protein needs are essential. The nutrient intake by a cow during the final trimester can have a long-term impact on the health of the calf she is carrying.
It will be more important than ever this year to have a solid prebreeding vaccination program with safe, efficacious products in place. With the additional environmental stress on her system, the cow will benefit tremendously from a modified-live virus (MLV) vaccine at prebreeding, and more importantly, so will her future fetus.
Prevent to protect. The diseases we are most concerned about are bovine viral diarrhea (BVD) Types 1 and 2, Infectious bovine rhinotracheitis (IBR), Bovine Respiratory
Syncytial Virus (BRSV), Parainfl uenza-3 (PI3) and Leptospira. We also need to think about protection against Campylobacter foetus (vibrio) and trichomoniasis, if there is prevalence in your area.
Trichomoniasis can cause infertility, early abortions and wreak havoc on reproductive effi ciency. Infected bulls spread the organism to cows during breeding. Vaccinating cows prebreeding with a vaccine labeled to protect against trichomoniasis is a key managementstrategy to control the spread of the disease.
The best timing for protection against reproductive diseases is to vaccinate 30 to 60 days prior to the breeding season. Work with your herd veterinarian to develop the best implementation of a MLV vaccine program in your herd. If your cow herd has never had a modifi ed-live virus vaccine, it is critical to give two doses the first year prior to breeding. The first dose should be given six weeks prior to breeding, followed by a second dose two to three weeks later.
Timing of prebreeding vaccination is key to help the cow mount a proper immune response prior to breeding. A modified-live virus vaccine is a key factor in protecting against the many effects of bovine viral diarrhea (BVD), including preventing persistently infected (PI) calves. If a cow has been properly vaccinated prebreeding with an MLV vaccine, then if she is
exposed to the BVD virus during gestation, her fetus has a much better chance of being protected from the BVD virus. Exposure to BVD during critical stages of gestation (45 to 160 days pregnant) can result in a BVD-PI calf.
Modified live virus IBR (rednose) vaccination prebreeding is also effective at protecting against abortions should the herd experience exposure to this virus.
Killed virus vaccines certainly have a place in cow herd vaccination programs; however, they lack the label claims for protection against BVD-PI and IBR abortions that many of the MLV vaccines contain. Visit with your veterinarian to establish a vaccination protocol that will protect your cow herd from disease and give your next calf crop a healthy start.
JERRY WOODRUFF, DVM, is a Senior Professional Services Veterinarian with Boehringer Ingelheim Vetmedica, Inc. and is based in Nebraska.