A study of lipid peroxidation and vitamin E in dairy cows with hepatic insufficiency

Sixteen dairy cows were studied to assess the status of the natural antioxi dant vitamin E and lipid peroxidation in their livers. Cows with liver fail ure (n = 7) showed clinical signs of a hepatic encephalopathy and had the f ollowing values of selected blood indices: AST > 80 U/l and GLDH > 15 U/l i n serum, and venous plasma ammonia > 35 mmol/l. The control group (n = 9) c onsisted of dairy cows which were recovering from surgery (omentopexy) and were free of any health complications. Blood was analysed for alpha-tocophe rol, aspartate aminotransferase, glutamate dehydrogenase, gamma-glutamyl tr ansferase, total bilirubin, ammonia, cholesterol, albumin, free fatty acids , glucose, and beta-hydroxybutyrate. Alpha-tocopherol, triglyceride and mal ondialdehyde were measured in wet liver tissue. The cows with hepatic failu re were clearly low in alpha-tocopherol and had significantly lower (P < 0. 01) plasma alpha-tocopherol than the controls. Both liver triglycerides and MDA were higher (P < 0.05) in the cows with fatty livers. It is concluded that the cows with liver failure had an increase in the intensity of hepati c lipoperoxidative processes and a low antioxidative status, which should b e taken into consideration in cases where treatment of the disease is propo sed.