Abstract: Effects of daidzein on the milk yield,components and hormones in milk of cows in late lactation were studied.Four Holstein dairy cows in the 7th month of late lactation were sampled and self-control method was used.Daidzein was added to the concentrated feed at the dose of 10mg/kg during the treatment stage.The results showed that daidzein could lessen the declining tendency of milk yield in late lactation and increased the milk yield to some extent.Lactoprotein was evidently increased(P<0.01) while butterfat was not evidently affected.The level of T₄ in milk was evidently increased(P<0.05);the level of GH,PRL,E₂ and TSH in milk prone to rose while T₃ prone to decreased.It could be concluded that daidzein could indirectly affect milk yield and components of milk by regulating the levels of intrinsic hormones.

Key words: Daidzein, Hormone, Milk yield, Lactoprotein, Butterfat

CLC Number: 

• S823.9+1