Submitted to: International Animal Agriculture and Food Science Conference
Publication Type: Abstract Only
Publication Acceptance Date: 7/28/2001
Publication Date: N/A
Technical Abstract: Storage of swine waste is associated with the microbiological production of a variety of odorous compounds. These compounds can contribute to health problems for swine facility workers and animals, as well as odors that affect local human populations. Microbial populations in stored swine waste are primarily low (G+C), Gram-positive anaerobic bacteria. Since monensin has been used to alter the bacterial population and metabolic end-products in the rumen largely through its effect on Gram-positive bacteria, it was decided to test the effects of monensin on stored swine waste slurry. Feces and manure slurry were collected from a local swine production facility. Manure slurry was combined with 20% (w/v) feces and aliquoted into glass bottles under gas, stoppered, and maintained under anaerobic conditions. Monensin (10 mM) was added to two bottles, and two bottles without monensin were used as controls. Gas production in the monensin samples was greatly reduced within 24 hr (<10% of controls), and this reduction was maintained over a 28 day test period. Methane production was also reduced (<5% of controls). However, volatile fatty acid production was only slightly decreased in the monensin samples. These results are quite different from those observed in the rumen. Viable bacterial levels as determined by anaerobic agar plating were consistent between the treatments. Since a shift in bacterial populations was probably occurring during incubations with monensin, total DNA was isolated from the samples. Changes in bacterial populations will be assessed using 16S rDNA Amplified Ribosomal DNA Restriction Analysis (ARDRA). The results of this study suggest that antimicrobial compounds may prove useful for reducing emissions from swine facilities.