THE INHIBITION OF METHANE RELEASE FROM THE CELLULOLITIC FERMENTATION AS AN EFFECT OF LEMURU FISH OIL ADDITION

Abstract

Ruminants, especially cattle fed by high level of forages, has become a special interest for nutritionist, because of its considerable contribution to the methane release to atmosphere. Ruminant nutrition research has been focused on finding the method to reduce methane production, because of the methane effect on global warming and its effect on the decreasing of energy efficiency of the diets. The compounds with the ability to capture electron such as poly unsaturated acids which were found in the fish oil was studied in this experiment. Two head of Ongole cattle were used in this experiment, as the donor animal to get the rumen fluid for fermentation. A small pieces filter paper was used as a source of cellulose for the substrate in the fermentation. Lemuru fish oil as poly unsaturated fatty acid in the level of 2.5, 5.0 and 7.5 % were used in this experiment to reduce methane produced by cellulolytic fermentation. The result showed that the addition of Lemuru fish oil in the fermentation medium could reduce methane production significantly. Fish oil in the level of 2.5, 5.0 a.nd 7.5 % reduced methane production 1%, 17% and 31%. The addition of fish oil did not affect on cellulolytic enzyme activity. The CMC-ase activities in the medium solution with 2.5, 5.0 and 7.5% addition of Lemuru fish oil, were 5.00, 4.08 and 4.01 U/g protein. The enzyme activities were not significantly different compare with the enzyme activity in the control medium solution (4.35 U/g protein). The average microbial protein content were 0.56, 0.43 and 0.46 mg/ml for the medium added by 2.5, 5.0 and 7.5% Lemuru fish oil respectively. Those values were not significantly different compare with the microbial protein in the control medium (0.62 mg/ml). In the closed fermentation experiment, with the same condition gave the result that acetic acid as well as the propionate acid were increased as an effect of the compounds, while the butyric acid remain constant. The total volatile fatty acid contents increased significantly from 22.08 pmol in the control to 34.42, 50.31 and 36.78 umol as an effect of 2.5, 5.0 and 7.5% Lemuru fish oil addition respectively. It could be concluded that Lemuru fish oil could be used as a compound to reduce methane production in celulolityc fermentation by rumen microbes, without any negative effects on the fermentation products as well as the CMC ase activity.