Successful Recipe for Immunity Includes Proper Mix of Vaccines and Nutrients

We probably don’t think of it this way, but the immune system is an energy user.

That’s how Scott Poock, DVM, Dairy Specialist with the Veterinary Medial Extension and Continuing Education at the University of Missouri – Columbia, sees it.

Consequently, there is a subtle— but crucial—interplay between herd nutrition and immunity.

“When you talk nutrition,” he said, “if an animal doesn’t get enough energy, and you vaccinate it, the immune system has to use the energy that is there, but it’s usually not enough to deliver a good response.”

That means the animal will not acquire the level of immunity desired. So, not only will you have potential disease problems down the line, but also the return on your investment in the vaccination will be low.

Sometimes, it may even mean decreased growth if the animal uses its limited energy to respond to the vaccine rather than build body mass.

“On the pig side, we know that if a vaccinated animal doesn’t have adequate energy, it will sometimes respond to a vaccine, but grow more slowly,” Poock explained. “Its body is essentially stealing some of the energy it would normally use on growth and allocating it to immune response.”

To assure that they get the required energy to develop the proper immunity, Poock recommends feeding calves more at a younger age because “when you feed more dry matter, you will get a better response to vaccines.” He says the dairy industry is beginning to recognize what recent data has revealed: that producers need to feed calves more at a younger age. And manufacturers of milk replacers have changed their recommendation accordingly.

Poock, who raises a few head of cattle himself, says he feeds 2 pounds of milk replacer per head per day—twice the amount commonly recommended by manufacturers. This is especially important when the weather is cold or any time calves are under more stress, such as during dehorning, transporting and weaning. He explained that stress not only uses up energy, but also causes the release of glucocorticoids, which depresses the immune system.

The increased intake he suggests must include both energy and protein.

“On the dairy side, energy consumption is mostly an issue with calves,” he said. “We are aware of the increased energy requirement for producing milk, so we usually provide that in adequate amounts for adult cows.”

The industry is also realizing the importance of protein. Accordingly, over the past 10-15 years, manufacturers have developed accelerated milk replacers that have a higher protein to fat ratio than in the past.

In addition to adequate energy and protein, Poock says micro-minerals contribute to immune response. They should be supplemented for both calves and cows, either by mixing them with feed or providing salt block trace minerals in proportions that correlate with the forage and soil composition of the geographic area where they are located.

“There are two arms in the immune system,” Poock explained. “One is the cell-mediated arm, which includes the killer cells that attack invading organisms. The other arm produces antibodies to the organism. Copper, zinc and chromium, for instance, stimulate neutrophils, which ingest invaders, while cobalt and selenium are important in cell-mediated reactions.”

A logical vaccine protocol also increases the likelihood of a healthy immune response. Here are a few tips from Poock in that regard.

• Wait until the calf ’s immune system is mature before beginning vaccinations. Most veterinarians recommend waiting until the calf is one month old to enable immune response.
• Reduce stressors, such as parasites and poor sanitation.
• Avoid vaccinating in conjunction with other stressful events, such as cold weather, dehorning, castration, shipping and weaning.
• Make sure the animals—especially calves—are getting enough energy before vaccinating.
• Provide adequate protein and minerals.
• Target specific vaccinations to those cows/calves that need them.
• Use proper timing, e.g. vaccinate prior to when the calf or cow would be susceptible or exposed to a disease.

When it comes to handling vaccines, Poock suggests the following:

• Handle vaccines according to label.
• Observe expiration dates and sensitivity to sunlight.
• Mix only small batches at a time and discard unused amounts within an hour or two.
• Keep vaccines in a cooler in warm weather.
• Avoid disinfectants with modified live vaccines.
• Use the recommend route (subcutaneous or intramuscular) for each vaccine.