EFFECTS OF DIFFERENT LEVELS OF FORAGE AND CONCENTRATE ON THE METABOLISM OF GLUCOSE, β-HYDROXYBUTYRATE AND NONESTERIFIED FATTY ACID IN LIVERS OF NONLACTATING GOATS
S. Zhuang*1, R. Yan*, W.C. Dong*, T. Zhang*, G.J. Chang** and X. Z. Shen**
*College of Animal Sciences and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P.R. China
**College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P.R. China
1Corresponding Author E-mail: firstname.lastname@example.org
The aim of this study was to investigate the effects of different levels of forage and concentrates diets on the metabolism of glucose, β-hydroxybutyrate (BOHB) and nonesterified fatty acid (NEFA) in livers of nonlactating goats. Six catheterized GuanZhong goats (40±2 kg weight) were fed high concentrate diet (HC, 40% hay, 60% concentrate) or high forage diets (HF, 60% hay, 40% concentrate). Blood samples were simultaneously taken from the portal, hepatic and arterial catheters at 0 h, before feeding, 2, 4, 6 and 8 h after feeding. The HC fed goats exhibited higher (P<0.01) plasma glucose concentration and arterial flow accompanied by NEFA, BOHB(P<0.01) and hepatic glucagons concentrations (P<0.10) while NEFA portal flow and BOHB hepatic flow decreased (P<0.05). Glucose portal-arterial concentration difference and hepatic-portal concentration differences in BOHB and NEFA tended to decreased (P<0.10) with increasing NEFA portal and hepatic arterial concentration differences (P<0.05) in HC fed goats. There were no differences in net flow of glucose, BOHB and NEFA across splanchnic tissues, but a decreased net portal absorption in NEFA (P<0.05) accompanied with a tendency for depressing its net PDV plus hepatic uptake (P<0.10). In conclusion, the high concentrates diet may increase hepatic gluconeogenesis in nonlactating goats.
Key words: Concentrate, Liver, Glucose, Nonesterified fatty acid, β-Hydroxybutyrate, Goat