EPA/DHA对体外发酵及瘤胃液脂肪酸组成的影响

试验旨在研究日粮中添加不同水平的DHA/EPA对体外发酵和瘤胃液脂肪酸变化的影响。试验通过采用持续动态人工瘤胃装置，向发酵罐中添加EPA/DHA，连续培养7 d，分析脂肪酸组成的变化及发酵模式的改变。试验结果表明，日粮添加EPA/DHA使瘤胃液pH升高（与CK相比，Trt1和Trt2分别升高了0.11和0.35），Trt2 与CK相比差异极显著（P<0.01）；与CK相比处理组3种主要挥发酸中乙酸浓度下降（P<0.01），丙酸浓度升高(P<0.01)，丁酸浓度下降(P<0.01)，总挥发性脂肪酸浓度与对照组相比略有下降但差异不显著（P>0.05）；日粮添加EPA/DHA使瘤胃液脂肪酸成分发生改变。与CK相比处理组C18∶0含量显著下降（P<0.01）； t 11 C18∶1含量显著升高（P<0.01）；c-9,t-11 CLA含量显著升高（P<0.01），但是两组之间差异均不显著。因此，日粮中添加不同水平的EPA/DHA可以改变瘤胃发酵模式，影响不饱和脂肪酸瘤胃氢化过程，使脂肪酸组成发生改变，为采用新的营养措施调控反刍动物产品中CLA的含量提供理论依据。

Effects of Dietary EPA/DHA Supplementation on Fermentation and Fatty Acid Profiles in Rumen Fluid from Artificial Rumen

The objectives of this study were to examine the changes of composition and content of fatty acid in ruminal fluid and the changes of volatile fatty acid in ruminal fluid when EPA/DHA was added in diet. The experiment using the RUSITEC(rumen simulation technique) apparatus. Treatments of the experimental diet were as follows: basal diet (CK, 40∶60 forage to concentrate),or a basal diet plus 0.65% EPA/DHA(Trt1) ,or basal diet plus 1.30%EPA/DHA(Trt2). Experimental period was consisted of 6 d for adaptation and 1 day for sampling. Culture fluid was collected every 2 h over a 12 h period on the last day of the experimental period. Compared with CK, C18∶0 decreased by 76.93% and 80.35% in Trt1 and Trt2, respectively; while the concentration of trans11C18∶1 increased by 185% and 127% in Trt1 and Trt2, respectively; and c9t11CLA increased by 147% and 222% in Trt1 and Trt2, respectively compared with CK. The concentration of VFA, transC18∶1 and c-9,t-11CLA in different sampling time were different. EPA/DHA supplementation could markedly affect VFA and fatty acids profile in rumen fluid.