Chemical Or Biological Additives

Science is working hard to develop chemical or biological additives which will eliminate or reduce odors associated with swine wastes. There are four general types of chemical compounds: (1) masking agents that override the offensive odors, (2) counteractants that are chemically designed to block the sensing of odors, (3) odor absorption chemicals that react with compounds in manure to reduce odor emission, and (4) biological compounds such as enzymatic or bacterial products that alter the decomposition so that odorous compounds are not generated. Some of these compounds are added directly to the manure pit while others are added to the feed. Many of these commercial products marketed for the control of odors have generally been disappointing. Masking agents, bacterial agents, and enzymatic digestive aids have been shown to be ineffective. Feed additives have been found to influence the odor of fresh feces and urine, but an odor panel was unable to detect any significant change in decomposing manure.

Many odor reducing additives are under development. Some of them appear to reduce odors. However, any swine producer who uses an additive should understand that most of these additives are still being developed and that every site is an experiment. Time and on-farm experimentation will determine which products are effective.

Return to Odor Control Return to The Land Application of Animal Manure.