Feeding minerals to cattle on pasture

Abstract

Mineral deficiencies and imbalances for cattle are reported from almost all regions of the world. The mineral elements most likely to be lacking under grazing conditions for ruminants are Ca, P, Na, Co, Cu, I, Se and Zn. In some regions, under specific conditions, Mg, K, Fe and Mn may be deficient and excesses of F, Mo and Se can be extremely detrimental. In most countries of the world, the principal means by which cattle producers attempt to meet mineral requirements of their grazing herds is through use of free-choice dietary minerals. As a low cost insurance to provide adequate mineral nutrition, a modified ‘complete’ mineral supplement should be available free-choice. Calcium, Cu or Se, when in excess, can be more detrimental to cattle production than any benefit derived by providing a mineral supplement. The major disadvantage to free-choice minerals is lack of uniform consumption by animals. Factors influencing consumption of mineral mixtures include: (1) soil fertility and forage type, (2) season of year, (3) available energy and protein, (4) individual requirements, (5) salt content of water, (6) palatability of mineral mixture, (7) availability of fresh minerals and (8) physical form of minerals. Safe, biologically available and palatable forms of minerals, at a fair price, allow both the user and manufacturer to realize a profit from their use. Mineral supplements need to be evaluated for accuracy of formulation and suitability for cattle. Most studies have shown positive responses of mineral chelates and complexes when compared to inorganic sources.