N-甲基-D,L-天冬氨酸(NMA)对育肥猪生长激素基因表达的影响

Effects of N-methyl-D,L-aspartate(NMA) on GH Gene Expression in Finishing Swine

以肥育猪为对象 ,探讨了日粮中添加 5 0 mg/ kg N-甲基 - D,L-天冬氨酸 (NMA)对其生长激素 (GH)基因表达的影响。结果显示 ,添加 NMA后 ,肥育猪日增重提高了 9.31% (P<0 .0 1) ;料重比降低了 7.16 % (P<0 .0 2 ) ;血清 GH含量提高了 92 .5 4% (P<0 .0 1) ;垂体 GH- m RNA水平提高了 15 3.0 3% (P<0 .0 1) ;下丘脑 c AMP水平降低了 2 1.89%(P<0 .0 1) ;腺垂体中 c AMP水平升高 88.5 7% (P<0 .0 5 )

Eighty-four finishing pigs of the live weight from 56 to 90 kg were used to study the effect of NMA on GH gene expression.The results of feeding trial showed that 50 mg/kg NMA supplementation improved the average daily gain (ADG) by 9.31%(P<0.01) and decreased the feed gain ratio(F/G) by 7.16%.Adding NMA had no significant effects on the feed intake(P>0.05).Assay of sample indicated that addition of 50 mg/kg NMA decreased the cAMP concentration in hypothalamus by 21.89%(P<0.01),whereas increased the cAMP concentration in pituitary gland by 88.57%.It was found that the addition of 50 mg/kg NMA enhanced the level of pituitary GH-mRNA by 153.03%(P<0.01).The results implicated that the addition of 50 mg/kg NMA in diet would improve the level of GH-mRNA in pituitary gland and promote the growth of pigs by enhancing the level of GH.