Effects of dietary supplementation of walnut meal on performance of high BCS dairy cows

The aim of this study was to investigate the effects of dietary supplementation of walnut meal (WM) on dry matter intake (DMI), milk yield, plasma metabolites and oxidative stress in fat dairy cows. Twenty four multiparous Holstein cows were randomly assigned to 2 dietary treatments: Control (fed basal diet, CTR) and Walnut meal (9.45% of DM, WM).The diets were fed starting from the day of parturition to 21 d postpartum. BCS losses tented to be higher (P<0.1) in the CTR group compared to WM group. DMI was lower (P<0.05) in the CTR cows at days 5, 9, 16, 20 and 21 postpartum, compared to the WN fed cows. The experimental diets did not influence glucose, BHBA MDA, TAC and milk yield or its composition. WM cows had numerically higher plasma insulin than CTR cows. Cows fed CTR presented higher plasma NEFA concentrations (0.56 mmol/L) than the WM group (0.53 mmol/L).Further studies with higher level and longer time needed to investigate the effect of walnut meal as a natural antioxidant in dairy cows feeding.

Keywords:

Walnut meal , Blood metabolites , Milk yield , Oxidative status , Fat cow