Effects of varying forage and concentrate content on metabolism of glucose, β-hydroxybutyrate and nonesterified fatty acids in livers of nonlactaing goats

摘要

Introduction Glucose is an important intermediary of metabolism in ruminants and nonmminants,a major energy source in the pregnant animal,and a primary precursor for lactose synthesis in lactation (Annison and Linzell,1964).Glucose is mainly provided by gluconeogenesis in the liver,utilizing some precursors such as propionic acid or glucogenic amino acid in ruminant animals.It well known that glucose metabolism has a close association with hepatic ketogenesis and lipid metabolism in liver where glucose metabolism is integrated with ketone bodies,nonesterified fatty acid (NEFA) and volatile fatty acids (VFAs) metabolism (Huntington et al.,1986).There were a few studiesfocused on effect of different concentrate content in a diet on metabolism in nonpregnant or nonlactating ruminants (Ross and Kitts,1973;Fujita et al.,2006).Our research is aimed to investigate the effect of varying forage and concentrateproportion on metabolism of glucose,β-hydroxybutyrate (BOHB) and NEFA in livers of nonpregnant and nonlacting goats.