Effects of feeding high concentrate diets on lactation indicators and antioxidant levels in the mammary glands of lactating goats

doi:10.11686/cyxb2016283

Abstract

Abstract: The effect of feeding high concentrate diets for extended periods on lactation indicators and antioxidant potential in the mammary glands of lactating goats, 12 health multiparous guanzhong goats in mid lactation were randomly allocated to two groups; one group receiving diets with low concentrate (concentrate∶roughage 35∶65) as the LC group (n=6), and another receiving high concentrate diet (concentrate∶roughage 65∶35) as the HC group (n=6). The experimental lasted for 12 weeks. At the end of the experiment, goats were slaughtered after overnight fasting. All goats were killed with neck vein injections of xylazine and pentobarbital. Mammary glands and other tissues were sampled and quickly placed in liquid nitrogen and stored at -70 ℃ for gene and protein expressions analysis. The results showed that milk production was significantly increased by feeding a high-concentrate diet and the percentage of milk lactose, protein and fat was significantly increased with lactation time. The expression of sterol regulatory element-binding protein 1 (SREBP1) and Glucose transport 1 (GLUT1) mRNA was significantly decreased (P<0.05), and AKT1 protein levels tended to be lower (P=0.08) in the HC group compared to the LC group. The HC diet moderately reduced the activity of T-AOC the enzyme (P=0.06) and GSH (P=0.08). These results suggest that feeding high concentrate diets reduced the antioxidant ability and significantly decreased the percentage of milk fat as well as down-regulated SREBP1 and p-AKT expression in the mammary glands.

TIAN Ping, SUN Li-Li, DONG Hai-Bo, TIAN Jing, DUANMU Yong-Qian, TAO Shi-Yu, NI Ying-Dong. Effects of feeding high concentrate diets on lactation indicators and antioxidant levels in the mammary glands of lactating goats[J]. Acta Prataculturae Sinica, 2017, 26(4): 99-105.

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