中文摘要：

本试验旨在采用体外产气法研究沙柳混合发酵饲料对绵羊瘤胃内环境参数的影响。按沙柳不同添加量（36.44%和67.08%）调制成2组混合发酵饲料，分别用FF1组和FF2组表示，在各组中添加等量的复合菌剂（活菌数≥5×10^7 CFU/g），考察发酵饲料在发酵1、3、5、7、10、12、15、22、30、45和60 d时，体外培养96 h的产气量、产气动力学参数和24 h瘤胃发酵参数变化。结果表明：1）随着发酵时间的延长，沙柳混合发酵饲料96 h累积产气量、可消化有机物和代谢能均呈现先下降后升高的趋势。2）沙柳混合发酵饲料经过发酵处理显著提高了瘤胃微生物蛋白和总挥发性脂肪酸浓度（P〈0.05），显著降低了pH、氨态氮浓度、丁酸浓度和乙酸/丙酸（P〈0.05）。结果提示，在体外培养条件下，按沙柳添加量36.44%和67.08%调制的2种发酵饲料可以有效地促进瘤胃微生物发酵，提高瘤胃发酵的能量利用效率，增加了微生物蛋白在瘤胃内的合成，且添加量为36.44%时优于为67.08%时。

英文摘要：

The current experiment was carried out to investigate the effects of Salix mixed fermented feed on ruminal environmental parameters by in vitro gas production method. According to the different proportion of Salix （36.44% and 67.08%）, two groups of mixed fermentation feed were made, represented by FF1 and FF2 groups respectively. Each group was added the same number of compound bacteria preparation （ live number≥5×10^7 CFU/g）. Gas production and gas production kinetic parameters in 96 h, and ruminal fermentation char-acteristic indexes in 24 h at different fermentation periods of 1, 3, 5, 7, 10, 12, 15, 22, 30, 45 and 60 days were determined, respectively. The results showed as follows：1） with the extension of fermentation time, ac-cumulative gas production in 96 h, digestible organic matter content and metabolizable energy were firstly de-creased and then increased. 2） The concentrations of volatile fatty acids and microbial protein were significantly increased （ P〈0.05） , while pH, the concentrations of ammonia nitrogen and butyric acid, and acetic acid/pro-pionic acid were significantly decreased by Salix mixed fermentation feed （ P〈0.05） . In conclusion, under in vitro culture condition, the two kinds of Salix mixed fermented feed with the supplemental proportion of Salix of 36.44% and 67.08% can effectively promote rumen microbial fermentation, raise energy utilization efficien-cy and increase the microbial protein synthesis in rumen, and the optimal supplemental proportion of Salix is 36.44% compared with 67.08%.