CORN CO-PRODUCTS Managing Sulfur Concentrations in Feed and Water

Sulfur (S) serves many purposes in the ruminant animal. It is a component of amino acids methionine and cystine, as well as B-vitamins, biotin and thiamine and a number of other organic compounds. Elemental S, sulfates, sulfuric acid, and hydrogen sulfide all may be present in ruminant nutrition. Elemental S, sulfates, and sulfuric acid are relatively non-toxic. Hydrogen sulfide, however, is highly toxic and is responsible for the rotten egg smell that is often attributed associated with S. For most ruminants, dietary S must be between 0.18 and 0.24% of DM to allow microbes to produce sufficient S-containing compounds to support microbial growth and to provide S-containing compounds for the host animal (NRC, 2005). All S-containing compounds, with the exception of thiamine and biotin, can be synthesized from methionine, and all organic Scontaining compounds can be synthesized from inorganic S by ruminal microbes (NRC, 1996).