摘要
应用放射免疫分析法(Radioimmunoassay.RIA),首次测定了14只西农萨能奶山羊初乳中17β—雌二醇(17β—E_2)和孕酮(P_4)的水平。结果表明,分娩0时17β—E_2含量最高(549.05±156.51pg/ml),为10天后均值的12.2倍;分娩后最初6小时17β—E_2水平波动在549.05—408.01pg/ml的范围内,然后陡然下降;2天后下降幅度逐渐减慢,到分娩5天以后,下降到较低水平。P_4的水平在分娩0时为1.883±0.937ng/ml,分娩后最初2天下降较快,随后逐渐变慢,6天后维持在0.7—0.8ng/ml的水平。用山羊初乳对12只西农萨能奶山羊实施颈部皮下注射。结果表明,与注射0天比较,注射后P_4水平立即下降,持续13天。其中第1、5、6、12天显著下降(P<0.05),其余9天均值下降到注射0天均值的80.3％,而对照组无变化(P>0.10)。17β—E_2水平变化不显著(P>0.05)。注射初乳后最初13天,注射组的17β—E_2/P_4的比值极显著地高于对照组(P<0.001)。以上研究结果表明,奶山羊初乳中17β—E_2和P_4水平的分泌范型与牛类似;给奶山羊注射初乳后,能引起其乳汁P_4水平下降和17β—E_2/P_4比值升高,但显示不出诱导发情的作用。
The concentrations of oestradio17β(17β—E_2) and progesterone(P_4) in the colostrum of Xinong Saanen dairy goats(n=14) were first measured by radioimmunoassay. On an average, The highest concentration(549.05±156.5pg/ml)of 17β—E_2 in the colostrum was shown at time 0 postpartum, which was over ten times more than the one in the milk after days 10 of partiurition. The levels of 17β—E_2 fluctuated in the colostrum during the first 6hrs postpartum and then declined sharply Two days later, the contents of 17β—E_2 in the colostrum reduced slowly and they decreased to lower levels in milk after d 5 of parturition. The contents of P_4 in the colostrum decreased more fast during the first 2 days of postpart um and then decreased slowly. The P, in milk kept at lower levels after d 6 of parturition. The twelve Xinong Saanen dairy goats were injected subcutaneously with the colostrum of Xinong Saanen dairy goats; other six Xinong Saanen dairy goats were used as control. The determination of the levels of P_4 and β—E_2 in milk showed that P_4 levels declined immediately after Injecting the colostrum. The levels of P_4 in the milk were lower for thirteen days after injecting the colostrum than thosc on day 0 before treatment, especially they reduced significantly on day 1, 5, 6 and 12 (P<0,05), and remained at the levels of 80.3％ of those on day 0, during other nine days. The levels of P_4 in milk did not showy signifincant difference (P>0.05)in control group. The ratios of 17β—E_2 (pg/ml) to P_4(ng/ml)were significantly higher (P<0.001)in treatment group than in control group during the first thirteen days after administration. These results showed that the patterns of 17β—E_2 and P_4 secretion in the colostrum of the goats are similar to those of cows. The levels of P_4 diminished and the ratios of 17β—E_2 (pg/ml) to P_4 (ng/ml) rose in the milk in dairy goats injected the colostrum but the effect of inducing oestrus was not observed
关键词
奶山羊
初乳
乳汁孕酮
Dair Gyoat, Colosrum, Milk Progesterone, Oestradiol—17β
