Effects of supplemental bupleurum extract on blood parameters, antioxidant status and immune function in heat-stressed dairy cows

摘要

Introduction Heat stress (HS) is one of the major abiotic stresses limiting the development of dairy industry.Though many strategies have been used to alleviate HS (Marai et al,1995;Zimbelman et al,2013),the losses from HS remain a major bottleneck restricting the development of the livestock industry.The genus Bupleurumis a well-known traditional Chinese medicine thathas been used for more than thousand years(Lin,1990),which contains many bioactive components (Contreras et al,2002).Its variouspharmacological functions have been reported,such asantipyretic (Chung et al,2010),antioxidant activity (Zhao et al,2012)and immunostimulant(Sun et al,2006) activities.To date,most of the previous research on bupleurum focused on the application of human and rat,but the effects of direct-fed bupleurumextract(BE) on the antioxidant status and immune responses in dairy cows are still unknown..Therefore,the objective of this studywas to investigate the effects of BE on routine blood parameters,antioxidant status and immune function in heat-stressed dairy cows.