No mineral supplementation Texas forages are deficient in key minerals for a majority of the year. Common problems of mineral deficiency include reproductive inefficiency, poor growth, and susceptibility to disease. Of particular importance are phosphorous and magnesium, and the trace minerals copper and zinc. Consult your County Extension Agent for detailed recommendations on mineral content. If you feed together, you'll either cheat lactating cows, waste feed on dry cows or, if you try to compromise, both.
Cattle require energy, protein, minerals, and vitamins.
Supplements should be chosen to make up for nutrient deficiencies. If protein is deficient, choose supplements based on protein content and cost. If both protein and energy are deficient, both must be considered, and fed at required rates, usually more pounds than when protein alone is needed. Mismatches of supplements and deficiencies affect performance, cost, or both. One implant given at least 90 days before weaning will average increasing weaning weights by 20 to 25 pounds.