Abstract: [Objective] This study compared the effects of two different ingredients of milk powder on the growth status and bone health of rats. [Method] Twenty-one 4-week-old SD male rats were randomly divided into control group and milk powder group. The milk powder group included Biostime Children's Growth milk powder （Golden）（hereinafter referred to as Golden Group） and Biostime Children's Growth Milk powder （Blue）（hereinafter referred to as Blue group）,and the corresponding diets were fed for 8 weeks. To explore the effects of milk powder supplementation on body weight,bone density,bone strength,serum calcium and immunity in rats.[Result] The food intake of the rats in the milk powder group was reduced,and the body weight was maintained at the normal level,which had no significant difference with the control group. Both kinds of milk powder can significantly improve the bone strength of rats,and the effect of Golden group is higher than Blue group. The effects of two kinds of milk powder on cortical bone mineral density and trabecular bone mineral density of rats were not obvious;Both kinds of milk powder can increase the thickness of bone trabecular and reduce the degree of bone trabecular separation,which shows that the bone metabolism of rats has a good regulation ability. The content of serum calcium in Golden group was higher than that Blue group because GOS could promote calcium absorption. Compared with the control group,IgM values of the milk powder group were significantly increased, and the milk powder of the Blue group showed a stronger regulatory effect,which may be related to the DHA content.[Conclusion] The two kinds of milk powder have good effects on enhancing bone strength, regulating bone metabolism and improving body immunity.

Key words: Biostime children growth milk powder, bone strength, bone metabolism, body immunity