[Objective] This study was to investgate the effects of lysine on the growth of sheep and its mechanism. [Method] Fifteen sheep about one-year old as experimental material were divided into three groups （group A, group B end group C）, into whose basal feed 0, 4 and 10 g h/sine were respectively added. After 28 d of feeding, the experimental sheep were all slaughtered for sampling; then total RNAs were extrac- ted from the samples and used to clone GHR and GAPDH genes via retrotrenscription for analyzing the expression abundance of GHR mRNA in Iongissimus dorsi muscle from different treatments. [Result] The expression of GHR mRNA in treatment B was significantly higher than that in treatment A（ P 〈0.01 ）, and significantly higher then that in treatment C （ P 〈0.05） ; while that in treatment C and treatment A was insignificantly different（ P 〉 0.05）. [ Conclusion] Addition of lysine into basal feed of sheep could dose-independently improve the expression of GHR gene in Iongissimus dorsi muscle.
[Objective] The aim was to study the effect of RPlys on digestive metabolism of nitrogen in sheep.[Method] The contribution of RPlys for nitrogen residual in sheep was researched by digestive metabolism test.[Result] The results showed that adding RPlys decreased excretion of urine nitrogen （P0.05） and had no significant effect on excretion of fecal nitrogen （P0.05）,and precipitation coefficient of nitrogen was increased （P0.05）.[Conclusion] RPlys is propitious to the aggradations of nitrogen in sheep.
