| In recent years, a large number of greenhouse gas emissions caused the greenhouse effect and other environmental problems become increasingly serious, more and more people have payed attention to. How to through the management method and animal breeding improvement groups of science makes in order to meet the people’s daily needs at the same time control and even reduce livestock caused greenhouse gas emissions, is one of the hot issues of concern to the industry in recent years. This experiment was conducted to study the effects of different concentrate to forage ratio of Qinchuan beef cattle methane emissions.Select a good body condition, similar weight(350±6.88 kg), the age of one-year-old Qinchuan bulls, steers and cows every three head. A 3*3 Latin square experiment was designed, divided into three groups for each treatment group three in feeding cattle. The test according to the Chinese beef cattle feeding standard(2004), the preparation of three kinds of nitrogen(crude protein level 16.44%), concentrate to forage ratio of 30:70(low energy group);50:50(mid energy Group); 70:30(high energy group) diet were fed. The environmental control metabolic warehouse real-time measure the methane emissions. Rumen puncture technique was used to analyze rumen fermentation.The results showed that dietary concentrate to forage ratio improved significantly reduced the Qinchuan cattle bulls, steers and heifers methane emissions(P<0.05). And in high-energy group energy levels, methane emissions from Qinchuan beef steers was significantly lower than that of cows and bulls(P<0.05), other dietary energy level steers,bulls, cows methane emissions no significant difference(P>0.05).In the rumen fermentation,improve dietary concentrate to forage ratio significantly decreased in Qinchuan cattle bulls,steers and cow rumen pH(P<0.05), while significantly reducing the Qinchuan cattle bulls,steers and cows rumen NH3-N concentration(P<0.05), but in the same energy level, bull,there were no significant differences between the steers and the cow rumen pH and between NH3-N concentration(P>0.05). The study found that increasing dietary concentrate to forage ratio significantly increased in Qinchuan cattle bulls, rumen total volatile fatty acid concentrations in steers and heifers(P<0.05), and significantly reduced the ratio of acetic acid and propionic acid(P<0.05). In the middle of dietary energy, acetic acid the ratio of propionic acid was significantly higher than that of cow steers and bulls(P<0.05). No significantdifferences in other energy levels(P>0.05). To improve the ratio of concentrate to roughage significantly improves the bulls, steers the butyrate concentration in the rumen fermentation of butyric acid(P<0.05) concentration in the rumen fermentation of the cow. There is an upward trend, but not significant(P>0.05), in the high energy group, steers the butyrate concentration highest(P<0.05), other energy levels, bulls, steers and heifers no significant difference(P>0.05).Conclusion: The results shows that increased dietary concentrate to forage ratio can significantly reduce feeding Qinchuan beef cattle methane emissions, and the methane emission of steers was the lowest, followed by cows and bulls. Increasing dietary concentrate to forage ratio can be significantly reduced feeding Qinchuan beef Cattle Rumen total volatile fatty acid production, and significantly reduce the ratio of propionic / acetic acid. In the fattening condition, improve dietary concentrate to forage ratio can be significantly improved feeding Qinchuan Cattle Rumen propionate concentration and steers of acetic acid and propionic acid ratio of lowest. This shows that Qinchuan cattle in the growth stages of fattening steers the rumen fermentation pattern is the best, followed by bulls and cows. |
PDF Full Text Request