With the Veterinary Feed Directive fully implemented this year, it will be important to build strong immune systems in our calves through sound nutrition to avoid the use of antibiotics. While overall nutrition is important to maintaining health, there are several key trace minerals that are 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 that 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 that 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 winter can tax the levels dams have to give, thus making supplementation of the cow herd with high quality mineral sources critical this 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 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.