CALF_News_October_November_2020

27 CALF News • October | November 2020 • www.calfnews.net “The rancher should work with a USDA-approved lab and a good veteri- narian,” Jones advises.“Make sure your veterinarian understands the process. The lab is the best source of informa- tion on how to make an effective vaccine. When we follow those instructions to the letter, we will have our best chance to make a viable vaccine. “Make sure your veterinarian col- lects and handles appropriate samples properly, so the organism isn’t damaged or killed. This increases the odds of a successful effort.” David Rethorst, DVM, Beef Health Solutions in Wamego, Kan., also recom- mends autogenous vaccines to help manage pinkeye. He says Mannheimia, Pasteurella, Mycoplasma and Histophilus somni are normal inhabitants of the respiratory tract that may cause a variety of enteric and respiratory illnesses. “We can culture those from perfectly healthy 3-day-old calves,” Rethorst reveals.“When I see problems with those bacteria, I look for what’s suppressing the immune system, whether that’s a trace mineral deficiency, mismanage- ment during the cow’s third trimester, or if we’re getting some fetal programming impact on the immune system.” Rethorst says that if he has a pinkeye occurrence caused by Moraxella bovoculi and has not had success with commercial vaccines, he recommends an autogenous product to buy time as he stimulates the animals’ immunity. He also orders autog- enous products for stocker operations because those animals can be highly stressed or mismanaged. Autogenous vaccines also have a role treating respi- ratory illness in light calves or weaned calves in the fall. “Don’t look at an autogenous vaccine as a cure-all,” Rethorst concludes.“What other stressors are tweaking the immune system, letting calves develop pinkeye or respiratory disease?” Chance Armstrong, DVM, food animal veterinary specialist at Louisiana State University School of Veterinary Medicine, says veterinarians may not know the true efficacy of autogenous vaccines when compared to available commercial vaccines. “Efficacy data is associated with USDA mandates through the Center for Veterinary Biologics,” Armstrong explains.“In certain situations, where herd management is good but traditional therapies have failed, I have suggested using autogenous vaccines.” Armstrong recommends autogenous vaccines when there are many strains or variables to certain diseases. Some isolates are not available in a commer- cial vaccine because the disease-causing “bugs” mutate often. Autogenous vac- cines are especially useful when a strain is ranch specific. Get ahead of a condition by utiliz- ing a solid vaccination program before sickness appears. It may not eliminate the disease, even with the best-designed vaccination program. The animal must have a sound, working immune system at the time of vaccination. Well-grounded management strate- gies such as parasite control, biosecurity, vaccinations, genetics and stress elimina- tion are crucial to preventing infections. Armstrong advises working closely with a veterinarian who understands the local or regional challenges associated with each ranch. Armstrong advocates low-stress cattle handling, an essential component to overall herd health and animal welfare. When producers limit handling stress, animals can respond more effectively to a vaccine. In Louisiana, stressors include extreme heat, humidity and poor han- dling. While no commercial vaccine is 100 percent efficacious, operators should give it every opportunity to be successful. “Start by looking at your herd health program,” Armstrong advises.“Are there things you can do better? Sometimes the challenging aspects of preventa- tive programs are easy for producers to ignore because they are more difficult to implement. I would be very critical of my herd health program before I change vac- cination protocols. “Understand the challenges and issues on your operation and which commer- cial vaccines are available. If you have used traditional therapies and still have a problem, consider an autogenous vac- cine. Understand it is a killed product that requires boostering three to four weeks after the initial vaccination. Vaccines cannot make up for poor management. Ranchers should review their management strategies and improve areas that have fallen behind. When producers do their homework and visit with their veterinarians, they can learn how autogenous vaccines can be another tool in the rancher’s toolbox.  Dr. Rethorst administers autogenous vaccines for enteric or respiratory infections when commercial vaccines are unavailable. Photo courtesy David Rethorst, DVM