【作者】 朱河水；

【导师】 王艳玲； 杨国宇；

【作者基本信息】 河南农业大学 ， 基础兽医学， 2001， 硕士

【摘要】 本试验研究了饲喂大豆黄酮对奶牛泌乳和几种激素水平的影响。 试验Ⅰ用4头处于第3泌乳期、产奶约7个月的中国荷斯坦牛，年龄6岁左右。采用前后自身对照方法，分为对照期和试验期，均为12d。对照期日粮中不添加大豆黄酮，试验期日粮中添加10ppm的大豆黄酮。 结果表明，饲喂大豆黄酮能缓解泌乳后期奶牛产奶量的下降趋势，并在一定程度上提高产奶量。乳成分分析结果表明，大豆黄酮显著提高乳蛋白的含量（P＜0.01），而对乳脂率的影响不大。激素分析结果表明，大豆黄酮显著提高血清中、乳中T₄的含量（P＜0.05）。血清中及乳中GH、PRL、E₂和TSH的含量均有升高的趋势，而T₃则有下降的趋势。与对照期相比，血清中E₂、GU、PRL和TSH含量分别提高了36.46％、33.75％、13.13％和5.65％；乳中E₂、GH、PRL和TSH含量分别提高了7.43％、6.79％、8.71％和3.76％；血清中和乳中T₃的含量则分别降低了25.67％和7.79％，差异均不显著 试验Ⅱ用14头胎次、泌乳期相似的黑白花奶牛。采用分组对照试验，试验期为30d。对照组日粮中不添加大豆黄酮，试验组日粮中添加10ppm的大豆黄酮。 结果表明，饲喂大豆黄酮能缓解泌乳后期奶牛产奶量的下降趋势，并在一定程度上提高产奶量。乳成分分析结果表明，乳蛋白有升高的趋势，而乳脂率有下降的趋势，差异均不显著。激素分析结果表明，试验第15d，大豆黄酮显著提高乳中GH的含量（P＜0.05）；试验第30d，显著提高血浆中CH（P＜0.05）和PRL的含量（P＜0.01）。另外，血浆中、乳中E₂、T₃和T₄的含量均有升高的趋势。与对照组相比，血浆中第30d的E₂、T₃和T₄分别提高了5.15％、8.38％和7.14％；乳中E₂、T₃和T₄分别提高了4.52％、22.86％和20.77％。 提示大豆黄酮可能通过调节内源性激素水平而间接地提高奶牛泌乳量和乳蛋白。更多还原

【Abstract】 Effects of daidzein on the lactation and the levels of some pertinent hormones of dairy cows were studied in the experiments.In experiment I , four 6-year-old Chinese Holstein cows in their 7th month of the 3rd lactation were studied. Self-control method was used and the test was divided into control and treatment periods. Daidzein was added in the concentrate by lOppm during the treatment period, while during the control period daidzein was not added. The results showed that feeding daidzein can lessen the decline tendency of milk yield in later lactation phase and improve the milk yield to some extent; the concentration of lactoprotein was significantly increased(P<0.01) while the milkfat percentage was not evidently affected by daidzein administration. The T4 level of the serum and of the milk were all markedly raised (PO.05), and the levels of GH, PRL, E2 and TSH of the serum as well as of the milk had increasing tendencies while T3 showed a tendency of decline; compared with the control, the levels of ?, GH, PRL and TSH of the serum in the treatment were respectively increased by 36.46%, 33.75%, 13.13% and 6.65%, and those of the milk were respectively raised by 7.43%, 6.79%, 8.71% and 3.76%, while the T3 levels of the serum and of the milk were dropped by 25.67% and 7.79% respectively, but all the differences were not evident.In experiment II, 14 Holstein dairy cows similar in parturition37numbers and lactation period were divided into treatment and control groups. The test lasted 30 days, during which the treatment concentrate was added with 10ppm daidzein while there was not daidzein addition in the control concentrate. The results showed that feeding daidzein can lessen the decline tendency of milk yield in later lactation phase and the milk yield was improved to some degree; the content of lactoprotein was increased while the milkfat percentage was dropped, but all the differences were not significant; the GH content of the milk on the 15d was evidently increased (P<0.05); the GH (P<0.05) and PRL (P<0.01) levels of the plasma on the 30d were markedly raised; in addition, all the levels of E2, T3 and T4 of the plasma as well as of the milk had increasing tendencies. On the 30d , compared with the control, the levels of e2, T3 and T4 of the plasma were increased by 5.15%,8.38% and 7.14% respectively and those of the milk were increased by 4.52%,22.86% and 20.77% separately.The results indicated that daidzein can indirectly increase milk yield and lactoprotein content of the treated dairy cows.更多还原