Bovine Viral Diarrhea: Be BVD Aware
Bovine viral diarrhea (BVD) is a viral disease of cattle and other ruminants that, if it infects your herd, can have dire consequences for your operation’s bottom line. It can be tricky to detect in both individual animals and your herd, until it’s too late.
According to the USDA’s Animal and Plant Health Inspection Service Veterinary Services Centers for Epidemiology and Animal Health, BVD’s most common effects are respiratory and reproductive problems. Reproductive disorders cause the most economic losses.
All cattle can become infected with BVD by coming in contact with an animal carrying the virus resulting in an acute case. While this infection is usually not fatal, the animal will be susceptible to secondary infections and disease while its immune system fights the BVD virus. An acquired infection may also cause infertility, abortion and congenital defects if a cow is infected during breeding season or while pregnant.
Transmission may also occur from an infected dam to her fetus sometimes resulting in the live birth of an infected calf. The infection in this calf will persist throughout its lifetime—called a persistent infection or PI—and it will shed the virus continuously.
The Academy of Veterinary Consultants reports that the reproductive losses associated with lower pregnancy rates, increased abortions and higher calf mortality are the greatest economic costs of exposure to PI animals. They also claim that up to 50 percent of persistently infected animals will appear normal and cannot be identified visually.
Signs of an animal with an acute BVD infection can include fever, lethargy, appetite loss, eye and/or nasal discharge, oral lesions, diarrhea, decreased milk production and respiratory problems. The best ways to ensure your herd doesn’t fall prey to BVD is by detecting and controlling infected animals and preventing future infections.
Hard to Spot, Easy to Find
The clinical signs of a BVD infection can range from no discernible sickness to very severe illness ending in the animal’s death. Your best partners in BVD testing, identification and eradication are veterinarians. They can help you determine the best plan for your herd, especially if BVD is suspected. If your herd is given the all-clear, they can help develop a good prevention strategy.
Many laboratory tests are available to determine if BVD is present within a herd. Consult your veterinarian and approved laboratory for the test that would work best for your herd.
Prevention and Eradication
To prevent and control herd infection or transmission to non-infected animals, vaccination is a good tool. Consult with your veterinarian on which vaccination program would work best in your herd. Some vaccinations, including those that contain live or modified-live virus, can’t be used in pregnant cattle because they can infect the fetus and cause abortion, stillbirth or developmental defects.
Good biosecurity measures should also be an integral part of any BVD management or prevention program. Since infected animals shed the virus through body secretions, transmission can occur during embryo transplant, rectal examination and artificial insemination. Be sure any tools or equipment used to work cattle have been sufficiently sterilized.
Prevent cross-contamination from infected animals by removing those that test positive for BVD, decreasing contact between animals by increasing bunk space, decreasing cattle density and improving your fences to keep your cattle in—and other cattle out. Consult with neighbors to prevent infections from other herds.
Prior to breeding season, test cows, calves and non-pregnant females without calves that have not been tested previously including any replacement females. Bulls can also carry and transmit BVD, so don’t forget to test them as well.
Managing your herd’s health by preventing an infection of BVD can remove important health risks to your herd. Testing,
vaccination, good biosecurity measures and maintaining good relationships with your veterinarian and neighboring ranchers are all valuable tools in the fight against BVD.
by Kristin Hawkins
Texas and Southwestern Cattle Raisers Association
To learn more about beef cattle management, take advantage of TSCRA’s educational resources:
TSCRA hosts the annual Cattle Raisers Convention, which offers a unique mix of classroom and hands-on demonstrations from leading experts. The next Cattle Raisers Convention is March 31 to April 2, 2017 in San Antonio.
TSCRA is also a coordinator for the Texas Beef Quality Producer program, a beef quality assurance program designed to promote good management practices for cattle producers.
The association also offers Ranching 101 seminars at its headquarters in Fort Worth to give participants practical, sound guidance on the tools and equipment needed to get started in ranching.
While these seminars are designed for people starting off in the ranching business or looking to improve their existing operation, anyone interested in the cattle business is invited to attend. Ranching 101 programs are on the third Tuesday of the month from 1:00 to 5:00 p.m. If you are planning to attend, please RSVP at 800-242-7820 or [email protected].
Ranching 101 is free to TSCRA members and $20 for non-members.
Texas and Southwestern Cattle Raisers Association (TSCRA) was formed in 1877 and is the largest and oldest livestock trade association based in Texas. TSCRA has more than 17,000 beef cattle operations, ranching families and businesses as members. These members represent approximately 50,000 individuals directly involved in ranching and beef production who manage 4 million head of cattle on 76 million acres of range and pasture land primarily in Texas and Oklahoma, but also throughout the Southwest.
Learn more at www.tscra.org.