Milk production and some blood metabolite responses to yeast supplementation in early lactating Holstein dairy cows

الملخص EN

The present study was undertaken to investigate the effect of supplementation of two commercial products, Tonilisat yeast (TY) and Grow yeast (GY) on milk production, milk composition and blood metabolites in lactating dairy cows.

Eighteen early lactating Holstein dairy cows were divided into three groups of six cows per each group for three months.

The supplement levels of TY and GY product were 3.

75 and 15g / cow/d, respectively, which were mixed with the concentrate mixture.

The results show that dry matter intake (DMI) was not (P > 0.

164) affected by TY or GY supplementation compared to the control group.

The inclusion of TY or GY increased (P < 0.

05) milk yield by 3.

76 and 2.

93 kg/d, respectively compared to the control group.

The enhancement in milk yield was 15.

5 and 12.

1% by TY and GY supplementation, respectively compared to the control group.

Both types of yeast products supplementation to early lactating dairy cows improved (P < 0.

05) fat corrected milk (FCM), energy corrected milk (ECM) and feed efficiency compared to the control diet.

Milk fat, milk protein and solids- not- fat (SNF) yields were increased (P < 0.

05) in the two yeast supplemental groups compared to the control animals.

TY yeast products inclusion in the diet increased (P < 0.

05) the serum total protein and globulin concentrations compared to the GY product and control groups, while both products had no significant effect on albumin concentration compared to the control diet.

Cholesterol concentration was increased (P < 0.

05) by adding GY to the diet of the dairy cows compared to the TY and control groups.

From the present results it can be concluded that both TY and GY products have favorable impacts on the productivity of dairy cows during early lactation.