An increased focus on preventive health programs is paying big dividends for U.S. beef producers. By working with their veterinarians to understand disease challenges and implement more aggressive prevention protocols, producers are realizing steady improvements in overall health, reproductive success and animal value at sale time.
Effective vaccination, nutrition and parasite control programs are all contributing to better production efficiency of U.S. cattle. Over the last 20 years we’ve seen efficiency gains around five to six percent annually. Today, we produce more beef per acre and more beef per animal than we ever have before. Better genetics are playing a role in those gains, but much of it is coming from herd health.
According to Mike Moore, DVM, professional services veterinarian, Novartis Animal Health, this renewed focus on veterinary consultation and adherence to vaccine protocols is the driving factor behind improved animal health and performance.
“Proper vaccination is really the most important element of a preventive health program,” said Moore. “And many of the vaccines available today have moved us away from a treatment scenario—where we were primarily treating animals with disease—to a prevention scenario, where we’ve been able to truly reduce the incidence of disease,” he added.
BVD Remains A Top Threat
Respiratory and reproductive diseases are still the greatest threats to beef cattle growth, development and breeding efficiency. Among the most common and damaging diseases—BVD, BRVS, IBR, PI3 and Lepto hardjo-bovis—BVD is perhaps the most challenging cattle disease.
“BVD is a complex disease that’s very difficult to control,” said Moore. “Part of the challenge can be attributed to prevalence alone, with 60 to 85 percent of cattle being exposed to the BVD virus and one-half to two percent persistently-infected.”1
BVD consists of hundreds of different viral strains, making it even more difficult to recognize the disease. Up to 90 percent of BVD infections are subclinical, meaning infected cattle show no outward signs.2 And because BVD is an immunosuppressive virus, much of the economic impact is the result of a weakened immune system, which often leads to secondary respiratory infections. The BVD virus is often a precursor to Pasteurella multocida, Histophilus somni and Mannheimia (Pasteurella) haemolytica, along with other bacterial species.
BVD Strains and Control Strategies
BVD strains generally fall into two broad genotype categories—Type 1 and Type 2. BVD viral strains are further classified according to their biotypes or how they affect growth in cell culture in a laboratory. A virus is classified as cytopathic (CP) if it causes cell pathology, and noncytopathic (NCP) if no pathology of culture cells is detected.
“NCP is by far the more significant variation of BVD for cattle producers,” said Moore. “NCP BVD accounts for 90 to 95 percent of all outbreaks.3 And the NCP biotype is responsible for all BVD persistently-infected (PI) animals, as well as most BVD-induced abortions.”
Gaining control of BVD requires stringent biosecurity measures, along with effective vaccination. For maximum herd protection, veterinarians recommend choosing a vaccine that offers broad-spectrum coverage against field strains of both BVD Type 1 and Type 2 genotypes.
Moore notes Vira Shield® is a popular choice among veterinarians because it’s the only vaccine to feature three-way BVD coverage, including NCP Type 1 and Type 2, as well as CP Type 1. “Producers who want a combination of maximum flexibility and efficacy have found Vira Shield 6+VL5 HB to be a simple and effective way control BVD, as well as other major viral diseases. It’s a very convenient solution, because it’s safe to use in any animal at any time, including pregnant cows, heifers and calves nursing pregnant cows, without any of the label restrictions that most modified-live vaccines carry.”
U.S producers have made significant gains by stepping up their herd health programs. By continuing to focus on the highly prevalent diseases like BVD and working closely with their veterinarians, producers will make further gains in animal health, performance and profitability.
- Houe H. Epidemiological features and economical importance of bovine virus diarrhea virus (BVDV) infections. Veterinary Microbiology. 1999;64:89-10.
- Bovine Viral Diarrhea Virus Persistent Infection (BVD-PI) Ear Notch Testing Program for Cattle Herds; Washington State University, College of Veterinary Medicine; http://www.vetmed.wsu.edu/depts_waddl/dx/BVD.aspx
- Chase CL. Department of Veterinary Science, South Dakota State University, Brookings, SD.