Effect of different levels of 3-NOP on methane production and methanogens community by in vitro fermentation

BAO Wen-jun; ZHENG Ting-fang; LI Ti-yu; QIN Wei-ze

doi:10.13557/j.cnki.issn1002-2813.2023.16.001

Abstract：The study was to investigate the effect of different doses of 3-NOP added to high-concentration diets on methane production and methanogenic flora through in vitro ruminal fermentation.A completely randomized block design was used,including four groups:Control group(group C),low dose group(group LD),medium dose group(group MD)and high dose group(group HD),adding 0,0.4,0.8 and 1.2 mg 3-NOP to fermentation substrate,respectively.Fermentation culture in vitro was carried out for 24 h.The results showed that compared with control group,rumen methane production and methane production per gram of degradable substrate in each 3-NOP treatment group were significantly decreased(P＜0.05),but hydrogen production and hydrogen production per gram of degradable substrate were significantly increased(P＜0.05).The degradation rate of dry matter in rumen of HD group was significantly lower than that of other groups(P＜0.05),and the total gas production per gram of degradable substrate was significantly higher than that of other groups(P＜0.05).The Simspon index of ruminal fermentation in MD group was significantly lower than that in control group and LD group(P＜0.05).The relative abundance of Methanosphaera in each 3-NOP treatment group was significantly lower than that in control group.The experiment indicates that 3-NOP changes the flora structure of rumen methanogens and reduces methane production through the specific inhibition of methyl-coenzyme M reductase.