Abstract:

Objective: To investigate the effect of pregnant cow s milk on growth and development and blood lipid of juvenile female SD (Sprague-Dawley) rats. Methods: Sixty-four female SD rats aged 21 days old were randomly divided into 4 groups, which were fed pregnant cow s milk, postpartum cow s milk, commercial whole milk (mainly from pregnant cows) and artificial milk. The growth and development index of rats were observed and their blood lipid level was determined at 29 and 54 days old. Results: There was no statistically significant difference in serum high-density lipoprotein cholesterol (HDL-C) among 4 groups at 29 days old. Serum HDL-C levels in rats fed pregnant cow s milk, postpartum cow s milk, commercial whole milk and artificial milk were (0.66 ± 0.07), (0.60 ± 0.04), (0.69 ± 0.07) mmol/L and (0.56 ± 0.12) mmol/L at 54 days old, respectively. In addition, serum HDL-C level in rats fed pregnant cow s milk was higher than that in rats fed artificial milk (P < 0.05), and serum HDL-C level in rats fed commercial whole milk was higher than that in rats fed postpartum cow s milk or artificial milk (P < 0.05). No statistically significant difference in serum total cholesterol, triglyeride and low-density lipoprotein cholesterol among 4 groups at 29 or 54 days old was observed. Conclusion: The use of pregnant cow s milk or commercial whole milk can increase serum HDL-C in juvenile female SD rats.

Key words: pregnant cow s milk, juvenile female rat, estradiol, progesterone, blood lipid