|Jung, Yong Soo|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 4, 2004
Publication Date: June 21, 2004
Citation: Anderson, R.C., Callaway, T.R., Harvey, R.B., Jung, Y., Genovese, K.J., Edrington, T.S., McReynolds, J.L., Nisbet, D.J. 2004. Effects of formate and hydrogen on the inhibitory activity of 2-nitropropanol and nitroethane on ruminal methane production in vitro [abstract]. 4th INRA-RRI Symposium: Gut Microbiology. Paper No. 82/S41. Technical Abstract: Ruminal methanogenesis is an inefficient process resulting in losses of 2 to 12% of gross energy intake. Presently, we report the effects of two inhibitors on ruminal methane production in vitro. Mixed populations of ruminal microbes collected from a cow grazing rye grass were incubated (39 deg C) in duplicate for 24 h under CO2 or H2 (100%) with or without 60 mM added formate. Cultures were supplemented with or without 2-nitropropanol or nitroethane (5 mM). Methane accumulations were higher (P<0.05) in control cultures (containing no added nitrocompound) incubated with added formate (35.5 +/- 16.0 and 36.6 +/- 3.4 µmol/ml when under CO2 and H2, respectively) than in controls incubated without added formate (17.4 +/- 0.8 and 20.5 +/- 0.3 µmol/ml when under CO2 and H2, respectively). In the absence of added formate, methane accumulations in cultures incubated with 2-nitropropanol were numerically decreased by 33 and 8% when under CO2 and H2, respectively. When incubated with added formate; however, methane accumulations were reduced (P<0.05) 87 and 64% when under CO2 and H2, respectively. In contrast, methane accumulations were reduced more than 95% in cultures incubated with nitroethane, regardless of format addition. Accumulations of H2 in the 2-nitropropanol supplemented cultures were higher (P<0.05) than in controls only when incubated under H2, with or without added formate, but were higher in the nitroethane cultures only when incubated with both H2 and formate. Further research with these nitrocompounds may yield strategies to reduce costs associated with ruminal methane production.