title: Effect of antimicrobial agents on livestock waste emissions.
abstract: Various antimicrobial agents were evaluated with the purpose of reducing the microbial fermentation in stored cattle waste and the resulting odor emissions. Duplicate sealed 2-L flasks with 500 ml waste slurry, with and without antimicrobial inhibitors, were used to measure the production of short-chain volatile fatty acids, lactate, and total fermentation gas over 27-30 days. A combination of chlorhexidine diacetate (2 mM), iodoacetate (2 mM), and alpha-pinene (3.8 mM) reduced gas production 80% (1000 ml to 200 ml) and total volatile fatty acid production 50% (145 mM to 72 mM). Pinene had little antimicrobial effect; rather, it served as an effective masking agent, giving the waste a less offensive odor. A combination of chlorhexidine diacetate and the deaminase inhibitor, diphenyliodonium chloride (1.3 mM) had a similar effect in reducing short-chain volatile fatty acid production (145 mM to 80 mM). It is concluded that a combination of antimicrobial agents may be useful in controlling odor emissions and conserving organic matter in livestock wastes, therefore providing a potentially more useful byproduct waste when used as plant fertilizer.
authors.affiliation: Roman L. Hruska U.S. Meat Animal Research Center, USDA, ARS Clay Center, NE 68933, USA. varel@email.marc.usda.gov
authors.forename: V H
authors.initials: VH
authors.lastname: Varel
authors.forename: D N
authors.initials: DN
authors.lastname: Miller
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism; D000081008:Bicyclic Monoterpenes; D002417:Cattle; D002710:Chlorhexidine / Q000494:pharmacology; D004202:Disinfectants / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005232:Fatty Acids, Volatile / Q000032:analysis; D005740:Gases / Q000032:analysis; D007461:Iodoacetates / Q000494:pharmacology; D019344:Lactic Acid / Q000032:analysis; D008372:Manure / Q000032:analysis / Q000382:microbiology*; D039821:Monoterpenes; D013729:Terpenes / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D000081008:Bicyclic Monoterpenes; D004202:Disinfectants; D004791:Enzyme Inhibitors; D005232:Fatty Acids, Volatile; D005740:Gases; D007461:Iodoacetates; D008372:Manure; D039821:Monoterpenes; D013729:Terpenes; D019344:Lactic Acid; C005451:alpha-pinene; D002710:Chlorhexidine