Table 3. Deficient Minerals in Virginia
Deficient Marginal
Copper Calcium
Selenium Phosphorus
Sodium Magnesium
Zinc Iodine
Vitamins
Vitamins are compounds that are involved in the regulation of metabolism. These vitamins impact reproduction, skin and coat quality, and immune function. They are needed in minute quantities. Vitamins A, D, E and K are fat soluble vitamins that can be stored in the cow’s body. Vitamin C and the B complex vitamins are water soluble and are needed daily.
The rumen microbes produce all or nearly all of the B vitamins needed by cattle. Grazing cattle usually get enough vitamin A and E from lush green forage, and they produce vitamin D in response to sunlight. Vitamin C and K requirements are low and provided by the diet, so deficiencies are not a problem in cattle.
When grazable forage is not available such as in the winter-time, vitamin A, D and E supplementation is needed. These vitamins can be fed in the mineral mix or given as an injection every 2 to 3 months.