December 2015
Farm & Field

Maximizing Immunity

Preventing disease via nutrition is going to be more important than ever.

Many of you may have already heard of the new Food Safety Modernization Act proposed by FDA. In a nutshell, previous FDA rules were focused primarily on identifying food safety problems after they occurred and responding accordingly. FSMA seeks to help prevent food safety issues in both humans and animals through preventative controls throughout all levels of production, storage and distribution. Part of the fallout of FSMA is the topic of antibiotic use in meat animals. With debate still ongoing, one thing is clear, that reliance on antibiotic use in food animals is on a downward trend. With this in mind, it is going to be more important than ever to build strong immune systems in our calves through sound nutrition.

While overall nutrition is important to maintaining health, there are several key trace minerals typically deficient in the diet that play critical roles in the development and maintenance of the immune system in calves. These key minerals are copper, zinc and selenium.

Copper is needed for proper development of antibodies and white blood cells in addition to antioxidant enzyme production. Copper-deficient cattle are more susceptible to infections and do not respond as well to vaccinations. In addition, they tend to be less resistant to parasitic challenge. Studies have shown cattle receiving proper copper nutrition tend to be less susceptible to infections and have less severe infections when disease does occur.

Zinc plays an important role in the maintenance of skin, gastro-intestinal linings and the linings of the respiratory system. These are the body’s first defense against bacterial, viral and parasitic invaders. Additionally, zinc is crucial in non-specific immunity from neutrophils and phagocytic cells and antioxidant activity. Zinc is also necessary for development of antibodies needed for specific immunity.

Selenium works in conjunction with vitamin E in the removal of free radicals via antioxidant activity and is critical for phagocytic cell function in non-specific immunity. Research has shown selenium-deficient cells are less able to kill pathogens. Selenium deficient animals are less able to respond to a specific invader and have lowered antibody titers.

Since much of a calf’s body stores of trace minerals are obtained in-utero, especially during the last trimester, nutrition of the dam is crucial for the calf’s immunity. The dam’s nutritional status affects the calf in two ways. First, it affects the quality of the colostrum she is able to offer for passive immunity. Second, it provides necessary building blocks for when the calf’s body develops its own immunity.

Adding insult to injury is the fact that stress has a direct negative effect on immune function. For example, it has been shown that phagocytes do not respond normally to infection in the presence of cortisol (the "stress" hormone). Prolonged stress has been shown to actually increase an animal’s mineral requirements. The stress brought on by a harsh winter will tax the levels dams have to give, thus making supplementation of the cow herd with high-quality mineral sources critical during winter and spring. It’s important to keep high-quality supplements in front of the cows even after calving as the cows need to replenish body stores to prepare for breeding. Calves will also need access to supplements since some minerals such as copper are not transferred in milk in appreciable quantities. High-quality supplements will give them the building blocks they need for a strong immune system.

In summary, maximizing immune function via nutrition, especially trace mineral nutrition, is going to become increasingly important in beef production. SWEETLIX offers a wide variety of high quality supplements that will deliver essential minerals and vitamins to cattle in an ultra-convenient delivery system. For cows and calves coming out of a stressful winter and spring, consider one of the SWEETLIX CopperHead Supplements. SWEETLIX CopperHead Supplements are fortified at 150 percent of NRC recommended levels of copper and zinc, and SWEETLIX CopperHead Max Supplements at 250 percent of NRC recommended levels of copper and zinc. Both include highly available, organic forms of copper, zinc, manganese and cobalt. Visit to learn more about these products. Also like us on Facebook to learn more about how SWEETLIX can work for you.

SWEETLIX is a registered trademark of Ridley Block Operations

Jackie Nix is an animal nutritionist with Ridley Block Operations ( You can contact her at This email address is being protected from spambots. You need JavaScript enabled to view it. or 1-800-325-1486 for questions or to learn more about SWEETLIX mineral and protein supplements for cattle, goats, horses, sheep and wildlife. References available upon request.