添加Tween 20和Tween 80对绵羊瘤胃消化代谢的影响

Effects of Dietary Addition of Surfactant Tween 80 and Tween 20 on Ruminal Fermentation and Nutrient Digestibility of Sheep

选取装置永久性瘤胃瘘管和十二指肠瘘管的中国美利奴绵羊,采用5×5拉丁方试验设计,在饲喂玉米秸秆绵羊日粮中分别添加5,10 g/d Tween 20或3,6 g/d Tween 80,以空白为对照,以研究不同水平的非离子表面活性剂Tween 20和Tween 80对绵羊瘤胃消化代谢的影响。结果显示：与对照组相比,添加Tween后绵羊玉米秸秆的自由采食量以及各营养物质的自由采食量差异不显著（P〉0.05）;但瘤胃液pH值平均降低0.05-0.11;还原糖平均浓度分别增加15.69%,15.69%和14.71%。添加Tween有提高乙酸、丙酸和总挥发性脂肪酸平均浓度的趋势。添加3 g/d Tween 80后乙酸和总挥发性脂肪酸的平均水平均高于其它各组,其中较对照组分别提高6.7%（P〈0.01）和5.2%（P〈0.01）,其它各组间差异不显著。添加Tween对瘤胃液中氨态氮浓度、原虫数量以及干物质和半纤维素前胃消失率无显著影响,但纤维素在前胃的消失率由57%增加到60%（59.33%-60.01%）左右。添加3 g/d Tween 80后粗蛋白到达小肠的量较对照组增加14.20%,到达小肠率由77.89%增加到87.55%。以上结果提示：非离子表面活性剂Tween 20和Tween 80主要通增加纤维素在前胃的消失率和乙酸生成的途径对瘤胃发酵进行调控。

The experiment was designed as rumen and duodenal cannulae to examine th nal fermentation and nutrient digestibility. a 5 × 5 Latin square with five Chinese Merino male sheep with e effects of supplementation Tw In the experiment, the animals een and were given Tween 20 on rumia basal diet consiting of compound feed and corn straw. On the basis of the five experimental treatments control group was given the basal diet, supplemented with 5 g/d Tween 20,10 g/d Tween 20,3 g/d Tween 80 and 6 g/d Tween 80 respectively. Compared with control group,the amount of straw and DM intake was not influenced by Tween supplementation,but ruminal pH was decreased by 0. 05--0.11. Reducing sugar concentration by the 5 g/d and 10 g/d supplementation of Tween 20 and 3 g/d of Tween 80 was increased by 15.69 %,15.69 %, 14.71% respectively. The concentration of acetic acid, propanoic acid and TVFA tended to be increased in treated groups. Compared with the control,after addition 3 g/d Tween 80,the acetic acid and TVFA were increased dramatically by 6 . 7%（ P 〈 0. 0 1 ） and 5 . 2 % （ P 〈 0. 0 1 ） . Ammonia- N concentration and the amount of rumen protozoa in the rumen,and DM and hemicellulose degradation rate were not influenced by surfactant supplementation. The cellulose digestibility was increased from 57% to 60%. The amount of CP reached duodenum which was increased by 14.2% and the ratio of CP reached duodenum to intake from 77.89% to 87.55% by 3 g/d Tween 80 addition. Those results indicated that addition of surfactant Tween 20 and Tween 80 may regulate the ruminal fermentation by stimulating cellulose degradation and acetic acid production.