A review of microbiology in swine manure odor control

Generation of odors is a complex process that involves many bacterial species, producing an extensive array of volatile organic compounds under different manure storage systems currently used. A lack of understanding of the basic microbiology in manure leads to a poor odor prevention and control from animal wastes. This review covers pertinent available information about the indigenous bacterial genera in swine manure and their potentials of producing odorous volatile compounds. It addresses not only the odorous compounds in swine manure but also the inherent relations between the bacterial species and the related compounds. It also discusses several odor control techniques that have been developed based on microbial activities and the limitations with these techniques. Two bacterial genera, Eubacterium and Clostridium, are most likely the major contributors to odorous volatile fatty acids. It appears that anaerobic lagoons may not be an appropriate choice for treating swine manure for odor control due to the reduced methonogenic activities resulted from the low temperatures in lagoon liquid. Also, it seems questionable that the microbial-based manure additives will work, without aeration, in a real storage system for the purpose of odor control. ©2000 Elsevier Science B.V. All rights reserved.