Sulfur is a macro mineral. This means it is a dietary mineral that is required in relatively large amounts, and it constitutes a large portion of certain body tissues and fluids. Sulfur is required as a component of sulfur-containing amino acids cystine and methionine. As a component of biotin, sulfur is important in lipid metabolism. As a component of thiamin, it is important in carbohydrate metabolism.
When sulfur is deficient, a side effect can be retarded growth, primarily due to not meeting the sulfur amino acide requirements for protein synthesis. Sheep fed non-protein nitrogen to replace protein without sulfur supplementation show reduced wool growth. Wool contains approximately 4% sulfur.
Sulfur is related to the amino acids cystine, methionine, biotin, thiamin and coenzyme A. When it comes to toxicity awareness, sulfur toxicity is not a practical problem.
Nonruminants should be provided sulfur-containing proteins as a good source of sulfur. Ruminants and horses may be provided sulfur in protein, as elemental sulfur or as sulfate sulfur.
The body contains approximately 0.15% sulfur. Sulfur requirements are primarily those involving amino acid nutrition. Ruminants fed urea as a source of protein nitrogen may benefit from supplemental sulfur.