Effects Of Ovariectomy On Meat Production And The MRNA Expression Levels Of GHR、IGF-I And IGF-1R Genes In Some Tissues Of Doe Kids

The40F1hybrid doe kids of Boer Goats♂×Guanzhong dairy goats♀at age of5-month-old were randomly divided into treatment and control group, and the ewes in thetreatment group were ovariectomized at the beginning of the experiment and the controlgroup was not done to explore the effects of ovariectomy on the meat productionand growth and development of kids. The two groups were kept under the same condition ofstall-feeding during the whole test. Ten kids were chosen randomly from the two groups toslaughter after2months of the test. The about5g samples were collected respectively fromliver, longissimus muscle, leg muscle and perirenal fat to determine the relative expressionlevels of GHR, IGF-1and IGF-1R gene by Real-time quantitative PCR (qRT-PCR). Theresults were as follows:1. The average daily gain of kids ovariectomized was Increased by11.30%and theslaughter rate was raised from42.41%to45.62%. The Lean percentage was also increasedfrom34.81%to36.42%.2. In this study, the expression levels of GHR gene in liver, longissimus muscle, bicepsfemoris and perirenal fat tissues of ovariectomized female goats were3.21times(P<0.01),4.87times (P<0.01),3.19times(P<0.01) and1.91times (P<0.05) more than that of controlgroup respectively.3. The relative expression levels of IGF-1gene in longissimus muscle and liver of kidsovariectomized were6.19times and6.10times more than that of control group respectively(P<0.01), mRNA levels in biceps femoris were more than that of control group, but thedifference was not significant (P>0.05). As to perirenal adipose, the relative expression levelsof IGF-1gene in treated group were both increased compared with the control group, but thedifferences were not significant (P>0.05).4. The relative expression levels of IGF-1R gene in longissimus muscle and bicepsfemoris of ovariectomized ewes were were11.86times and9.96times more than that ofcontrol group, respectively (P<0.01), and was4.86times more than that of the control groupin biceps femori (P<0.05), and there was no significant different in perirenal adipose (P>0.05). Above all, the daily gain, slaughter rate and lean percentage were increased byovariectomy. The relative mRNA expression levels of GHR, IGF-1and IGF-1R genes of liverand longissimus muscle, the expression levels of GHR and IGF-1R genes of biceps femoris,and the expression levels of GHR genes of perirenal fat tissues were raised by ovariectomy.