Reduction of Odorous Sulfide and Phenolic Compounds in Pig Manure Through Diet Modification

Purdue University 2000 Swine Research Report. Increased public concern, legislation and environmental regulations have focused on pollution and have created a major threat to the viability and growth of the pork industry. Even though water pollution control has been the major focus of regulations and concern, recent public concerns and law suits have revolved around odors from pork operations. Several communities are creating zoning ordinances in an attempt to keep the pork industry from expanding. Most research has focused on measuring odor and gas intensity and occurrence (primarily ammonia, hydrogen sulfide, skatole, indole, aliphatic aldehydes, mercaptans, and amines) with proposed attempts to reduce or mask odors. The first line of defense against high concentrations of any emitted aerial contaminant is source control. In the case of swine odor, the obvious source control technique is diet manipulation. However, little research has been conducted on dietary modification or pre-excretion control to alter fresh and stored swine manure odors, yet fresh manure from pigs is an initial source of odors. Consequently, determination of the biological creation of gaseous compounds, reduction of precursor compounds creating odors, and development of effective biological control is needed for efficient and long lasting odor control. Research was initiated to develop ways to significantly reduce odors, especially sulfidecontaining odors, from pork operations with diet modification while sustaining efficient pork production. The objective of this study was to determine the effects of dietary methionine and cystine level, and cellulose and anthraquinone additions to the diet on production of odorous sulfide compounds and other odorous compounds from cecal contents, fresh manure and stored manure.