木薯残渣作为粗饲料对肉牛生长性能、养分消化及瘤胃发酵性能的影响

Effects of cassava residue as rouge on growth performance,nutrient digestion and rumen fermentation performance of beef cattle

文章旨在探讨日粮添加不同水平的木薯残渣替代水稻秸秆对肉牛生长性能、养分消化及瘤胃发酵性能的影响。试验将体重接近的96头肉牛随机分为3组,每组4个重复,每个重复8头牛。在为期140 d的饲养试验期间,对照组肉牛饲喂水稻秸秆为24%的全混合日粮,T1和T2组饲喂用50%和100%木薯残渣替代水稻秸秆的全混合日粮。结果:随日粮木薯残渣替代水稻秸秆水平的升高,71~140 d肉牛的平均日增重显著升高(P<0.05)。24%木薯残渣组140 d肉牛的体重、71~140 d饲料报酬及1~140 d平均日增重和饲料报酬均显著高于24%水稻秸秆组(P<0.05)。与对照组相比,24%木薯残渣组显著减低了肉牛中性洗涤纤维和酸性洗涤纤维摄入量(P<0.05),但有机物和中性洗涤纤维表观消化率显著提高(P<0.05)。随着日粮木薯残渣替代水稻秸秆水平的升高,细菌总数表现为显著升高(P<0.05),但白色瘤胃球菌数量表现为显著降低(P<0.05)。与对照组相比,12%和24%木薯残渣组瘤胃产琥铂酸丝状杆菌和产甲烷菌数量表现为显著降低(P<0.05)。结论:在本研究条件下,用100%的木薯残渣替代水稻秸秆可以提高肉牛的饲料效率和纤维表观消化率,降低甲烷排放量。

The experiment was conducted to investigate the effects of different levels of cassava residue supplementation with rice straw on growth performance,nutrient digestion and rumen fermentation performance of beef cattle.A total of 96 beef cattle with similar body weight were randomly divided into 3 groups with 4 replicates per group and 8 cattle per replicate.During the 140 d feeding period,beef cattle in the control group were fed a total mixed diet containing 24%rice straw,while those in the T1 and T2 groups were fed a total mixed diet containing 50%and 100%cassava residue instead of rice straw.Results:The average daily gain of beef cattle during 71~140 days was significantly increased with the level of cassava residue replacing rice straw increasing(P<0.05).The body weight of beef cattle at 140 d,the feed reward at 71~140 d and the average daily gain and feed reward at 1~140 d in 24%cassava residue group were significantly higher than those in 24%rice straw group(P<0.05).Compared with the control group,the intake of neutral detergent fiber and acid detergent fiber in 24%cassava residue group was significantly decreased(P<0.05),but the apparent digestibility of organic matter and neutral detergent fiber was significantly increased(P<0.05).With the increase of the level of cassava residue replacing rice straw,the total number of bacteria was significantly increased(P<0.05),but the number of Ruminococcus alba was significantly decreased(P<0.05).Compared with the control group,the numbers of filamentous bacilli and methanogens in rumen in 12%and 24%cassava residue groups were significantly decreased(P<0.05).Conclusions:Replace rice straw with 100%cassava residue can improve feed efficiency and fiber apparent digestibility,and reduce methane emissions of beef cattle under the present conditions.