ARS | Publication request: EFFECT OF SELECT NITROCOMPOUNDS ON RUMINAL FERMENTATION; AN INITIAL LOOK AT THEIR POTENTIAL TO REDUCE ECONOMIC AND ENVIRONMENTAL COSTS ASSOCIATED WITH RUMINAL METHANOGENESIS

Submitted to: Bioresource Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 4, 2003
Publication Date: August 20, 2003
Citation: ANDERSON, R.C., CALLAWAY, T.R., VAN KESSEL, J.S., JUNG, Y., EDRINGTON, T.S., NISBET, D.J. EFFECT OF SELECT NITROCOMPOUNDS ON RUMINAL FERMENTATION; AN INITIAL LOOK AT THEIR POTENTIAL TO REDUCE ECONOMIC AND ENVIRONMENTAL COSTS ASSOCIATED WITH RUMINAL METHANOGENESIS. BIORESOURCE TECHNOLOGY. 2003. V. 90. P. 59-63.

Interpretive Summary: Methane is a gas produced in the stomach (rumen) of animals like cows and sheep. The production of methane is an inefficient process of digestion because it results in the production of an energy source that cannot be used by the animal. We conducted laboratory experiments to determine if certain compounds could used to decrease methane production in cows. All of the compounds we tested decreased methane production more than 50% and were better than any products currently being used by the livestock industry. None of these compounds caused bad effects on the processes of digestion that would occur in a cow. This research will lead to the development of new and improved methods to reduce methane production by cattle and sheep and will thus help producers reduce costs of feeding their animals. The ultimate beneficiaries of this research will be consumers who will not have to pay as much for beef and lamb products.

Technical Abstract: Methane production by ruminal microbes during the digestion of feeds is an inefficient process that results in the loss of 2 to 12% of the gross energy consumed by ruminants. Presently, we report the effect of three inhibitors on ruminal methane production in vitro. Mixed populations of ruminal microbes collected from a cannulated cow maintained on an alfalfa hay: corn diet (1:1) were incubated at 39 deg C for 24 h under a 100% carbon dioxide gas phase in closed tubes with 72 mM added sodium formate and supplements of 12 mM 2-nitropropanol, nitroethane or nitroethanol (experiment 1) or with 2, 12 or 24 mM nitroethane or a combination of 12 mM nitroethane (experiment 2). Controls containing no added nitrocompound were incubated simultaneously as controls. Methane concentrations were reduced (P<0.05) from those measured in control incubations (27.6 +/- 2.1 and 17.7 +/- 0.8 umol/ml; mean +/- SD from experiments 1 and 2, respectively) by at least 57% and as much as 94% within the nitrocompound supplemented incubations. By comparison, the widely fed methane inhibitor, monensin, typically reduces ruminal methane production by about 33%. Concentrations of volatile fatty acids, ammonia and hydrogen that accumulated in the nitrocompound supplemented incubations were not markedly affected compared to those produced by control cultures despite the dramatic reductions in methane produced. These results demonstrate that 2-nitropropanol, nitroethane and nitroethanol are effective inhibitors or ruminal methane production.