The value of mineral supplementation is either discounted or overlooked by many beef cattle producers. Mineral supplements make up a small part of the total diet, but can play a big role in the overall performance of beef cattle. The importance of providing a mineral supplement becomes evident once you understand how it can affect animal performance.

Calcium (Ca), phosphorous (P), and magnesium (Mg) are often associated with bone development and growth, but these minerals serve other vital functions, including: growth, energy utilization, membrane structure, muscle contraction, and hormone secretion.

The ratio of calcium to phosphorous in the total diet is also important. While cattle can tolerate ratios of between 1:1 and 7:1, excessive calcium may decrease the absorption of other minerals. Therefore, a ratio of calcium to phosphorous between 1.5:1 and 3:1 is recommended. Deficiencies in calcium and phosphorous or an imbalance in the calcium to phosphorous ratio can result in decreased fertility, milk production, growth, and feed efficiency, as well as an increased incidence of metabolic diseases such as urinary calculi.

Potassium (K), sodium (Na), and chlorine (Cl) are important in water and acid-base balance, muscle contraction, nerve signal transmission, and enzymatic reactions. A deficiency of these minerals can result in decreased intake, gain, and milk production.

Sulfur (S) is required by ruminants for the synthesis of the sulfur containing amino acids and the B-vitamins thiamin and biotin. Sulfur is also used in the detoxification of poisonous compounds like those potentially found in most sorghum forages. A sulfur deficiency can result in reduced intake, gain, and digestibility and animals may be more susceptible to acidosis.

Trace minerals are needed for optimal growth and performance and many play a role in immune function. The trace minerals commonly supplemented to cattle include: cobalt, copper, iodine, iron, manganese, selenium, and zinc. Trace minerals are required at very small concentrations, making deficiencies difficult to recognize. Deficiencies can result in decreased intake and gain, reduced fertility and libido, retained placentas, abortions and stillbirths, low birth weights, and poor calf performance.

It is also important to monitor mineral consumption on a herd basis. Simply providing a mineral supplement will not ensure that deficiencies are met. Intake of a free choice mineral supplement will vary from animal to animal and change with the animal's requirements and the mineral content in the forage and any supplements. A reasonable range for mineral intake is 2 to 5 ounces per head per day, depending on the composition of the mineral supplement and the factors previously mentioned. Generally, consumption is lower during the summer months and higher in the winter months due to the mineral levels in growing versus dormant forages.

Providing a complete mineral supplement can greatly affect the performance of beef cattle. Marginal mineral deficiencies can easily go undetected, resulting in decreased reproductive efficiency, poor growth performance, and depressed immune function. All of these factors ultimately affect profitability. Providing a free-choice, complete mineral supplement all year is cheap insurance against the many problems associated with mineral deficiencies.