Sulfur in Livestock Nutrition

Sulfur is essential for all animals because S-containing compounds that have metabolic, structural, and regulatory functions are ubiquitous. Because S is not stored in the body, animal diets should contain a relatively constant supply of S. The S-containing amino acids are important components of many proteins, enzymes, and several hormones. Many enzymes contain S, and S plays important roles in their activities. Disulfide bonds are essential for enzyme structure and sulfhydryl groups function as sites of hydrogen binding, for interaction of substrates with active sites of enzymes and for binding of prosthetic groups of enzymes with substrates. Several peptide hormones contain S. Insulin contains disulfide bonds between its two peptide chains, as well as within one of the peptide chains. Glucagon and ACTH contain S amino acids. Collagen, the major structural protein in animal tissues, contains S amino acids. Rumen bacteria rapidly reduce inorganic S and incorporate the reduced S into organic compounds.