Abstract: Effect of isoflavones on the proliferation and lactation of mammary epithelial cell of dairy cow were determined in vitro. The mammary epithelial cells during the logarithm growing period were cultured with serum-free medium for 24 h and synchronized. The experiments were assigned into 5 groups(0,1,10,100 and 1000 mg/L isoflavones).After 48 h treated with different concentration of isoflavones,the proliferations and viabilities of cells were determined by CASY cell count technology. The secretion of β-casein and lactose of cells were determined by high efficiency liquid chromatography(HPLC) and the secretion of triglyceride of cells were determined by triglyceride test kit. The results showed that 10,100 and 1000 mg/L isoflavones significantly improved dairy cow mammary epithelial cell proliferation(P<0.05) and the secretion of β-casein,lactose and triglyceride compared with the control group(P<0.05).Therefore,10,100 and 1000 mg/L of isoflavones could advance the proliferation and lactation of mammary epithelial cell of dairy cow,and it was concentration-dependent.

Key words: isoflavones; mammary epithelial cell of dairy cow; proliferation; lactation; high efficiency liquid chromatography