Metabolism of flaxseed iignans in rumen and its impact on ruminal metabolism in goats | 亚麻籽木脂素在山羊瘤胃中的转化及其对瘤胃代谢的影响

中国人. 选用6只（46、2早）装有永久性瘤胃瘘管及临时性颈静脉插管的淮南山羊，进行交叉试验。试验期按体重灌胃50mg・kg. 1质量分数为20％亚麻籽木脂素提取物，分别用高效液相色谱法测定木脂素和挥发性脂肪酸含量，研究亚麻籽木脂素在山羊瘤胃中的转化及其对瘤胃代谢的影响。结果表明，在对照期瘤胃液中存在较低质量浓度的亚麻籽木脂素（0．003mg・mL. 1）、肠内酯（0．007mg・mL. 1）及肠二醇（0．017mg・mL. 1），但血清中未检测出木脂素成分。灌胃木脂素提取物能显著提高瘤胃液及血清中上述3种动、植物木脂素含量；同时，木脂素化合物使总脱氢酶活性升高25．5％（P〉0．05），并使瘤胃液pH值和氨氮含量分别降低1．1％（P〈0．05）和36．3％（P〈0．01），微生物蛋白及总挥发性脂肪酸含量分别升高70．1％（P〈0．01）和37．4％（P〈0．01）。结论：在饲喂青干草及豆粕型精料日粮条件下，瘤胃液中存在植物木脂素和2种最主要的动物木脂素。灌胃亚麻籽木脂素提取物后能显著提高3种木脂素含量，且均能被吸收进入血液。木脂素可以直接或间接影响瘤胃内微生物活性，从而改善瘤胃代谢水平。[著者文摘]

英语. The metabolism of lignans in the rumen and its impact on ruminal metabolism was investigated in 6 Huainan goats （4 ♂ , 2 ♀ ） fitted with permanent rumen fistulae and temporary jugular catheter which were supplied with flaxseed lignan crude extract （50 mg ・ kg. 1 ） via rumen fistulae. The concentrations of liguans were analysed by high performance liquid chromatography （HPLC） ; the concentrations of volatile fatty acids （VFA） in ruminal fluid were measured by gas chromatography （GC）. The result showed that there were low levels of secoisolariciresinol diglusoside （SDG）, enterodiol （END） and enterolaetone （ENL） in ruminal fluid under the basal diet conditions, and their concentrations were 0. 003, 0. 017 and 0. 007 mg ・ mL. 1 , respectively, whereas the concentrations of all 3 lignans were below the level of detection in serum. Exposure to SDG crude extracts could significantly increase the concentrations of lignans both in serum and ruminal fluid, and meanwhile, the levels of pH and NH3-N were lowered by 1. 1% （P 〈 0. 05） and 36. 3% （P 〈 0. 01 ） , and the concentrations of microbial crude protein （MCP） and total volatile fatty acids （TVFA） increased by 70. 1% （P 〈 0.01 ） and 37.4% （P 〈 0. 01 ）, respectively, and the activity of total dehydrogenase （TDHA） was also increased by 25.5% （P 〉0. 05） in ruminal fluid. Conclusion： both plant and mammalian lignans （ cnterolactone, ENL; enterodiol, END） were present in ruminal fluid but were not found in serum, when goats were fed the bas- al diet supplemented with flaxseed lignans, and all of the three kinds of lignans were observed in blood, suggesting that they could be absorbed through the wall of rumen. The SDG crude extracts could affect the activities of microorganism in rumen, and improve the metabolism of rumen.