Vaccinating key to raising healthy calves
“What you do on the ranch is extremely important to how well calves survive on the ranch,” Bruce Hoffman of Elanco Animal Health told more than 100 ranchers during a producer meeting in Hot Springs, S.D. “My goal is to leave here tonight, and feel like I have involved more people in animal health on the ranch.”
Elanco keeps track of about 40 percent of the cattle on feed. What they have found is a trend in feedlots to spend more money on health. “Treatment costs are going up. If we were successful, death loss should be going down,” Hoffman said.
Despite vast improvements in genetics over the last 20 years, death loss in the feedlot is still going up a tenth of a percent a year, Hoffman said. Vaccinations are improving all the time, but he questions whether producers handle it properly. “Are we doing what they recommend? Labor is always an issue. Do you vaccinate when the kids are home from school, or when the neighbors are available to help?” he asked. “When it is 108 degrees outside and dusty, do you decide to work calves anyway?”
Lifetime immunity is not whether the vaccination is a modified live or killed vaccine, but instead is dependent on when it is used during the animal’s life, and what is happening in the animal’s life at that time or at that point of production, Hoffman said. “The key is how you work with vaccines and the veterinarian. If there are problems, you need to let the veterinarian know. They want to know.”
John Rehmeier, who is a senior sales representative with Boehringer Ingelheim, explained to producers that cleaning a vaccine gun with mild dish soap can kill modified live vaccines.
Managing equipment and vaccines is an integral part of keeping cattle healthy, he said. “To clean vaccine guns, boil water and draw it into the gun and shoot it out at least five to six times. It is even better if you can take it apart and clean it more thoroughly if you have time.”
Rehmeier’s message reminded producers that preventing disease is better than having to treat it. However, maintaining clean equipment is only one piece of that puzzle. “I think it is critical that ranchers work with their veterinarian to determine which vaccination programs are best for their cattle because every operation is different,” he said.
Companies producing vaccines have strict rules they must adhere to to make products that are safe and effective, if they are used correctly. They must prove that the product they make is pure and potent, that the antigen they say is in the bottle is actually in there, and the product, if used as directed, is safe, Rehmeier said. Products also have to be efficacious, which means that they work. “The goal of vaccination is to use a product that will raise the level of immunity to resist pathogens,” Rehmeier said. “It keeps the animal from getting sick or minimizes the signs of clinical disease if it does get sick.”
Vaccinations differ from immunizations because the latter products emit an immune response. “Building an immune response allows the calf to have more disease resistance, which will improve its performance,” he said.
Rehmeier shared a study from a group of animals tested at the Meat Animal Research Center that showed 67 percent of those animals had lung lesions at slaughter, even though they never showed any clinical signs of sickness while they were alive. Research like this points to the importance of using vaccinations, and how effective they can be.
Each year, producers have to decide between using modified live (MLV) or killed vaccinations. Rehmeier said that MLVs typically have a one-dose regimen that provides good immunity, and doesn’t need a booster follow-up. MLVs also provide more rapid protection, longer lasting immunity which stimulates cell-mediated immunity, and allows for a more complete immune response. “The benefit of killed vaccines is they are safe to give at any time, and at any stage of production. I would note that when deciding which one to use, I wouldn’t recommend using modified live vaccines on pregnant animals,” Rehmeier said.
Handling MLVs can make all the difference in how the vaccine works, he said. “Don’t mix up any more vaccine at a time than what you can use in an hour. MLVs are very sensitive to UV sunlight, and if it’s mixed and left out too long, the sunlight can kill off the MLV.” ❖
— Clark is a freelance livestock journalist from western Nebraska. She can be reached by email at email@example.com.