The aim of this investigation was to determine serum levels of vitamin A, E, beta carotene, glutathione peroxidase (GSHPx), lipid peroxidation (MDA) and biochemical and haematological parameters during en¯urane anaesthetised dogs. Ten kangal dogs were used and all animals were anaesthetised with en¯urane for two hours and blood samples were taken before and 30, 120 minutes, 24 hours and 7 days during the anaesthesia. Vitamin E and beta carotene content were signi®cantly ( p 5 0 . 05 and p 5 0 . 01) higher before anaesthesia than after whereas serum GSHPx activity was not statistically dierent. However, serum levels of vitamin A and MDA were signi®cantly ( p 5 0 . 05) increased during the anaesthesia.
In general, serum levels of aspartate aminotransferase, alanine aminotransferase, albumin, glucose, urea and creatinine were signi®cantly ( p 5 0 . 05 and p 5 0 . 01) increased during anaesthesia and returned to near normal values after 7 days of anaesthesia, whereas the white blood cell count was signi®cantly ( p 5 0 . 05 and p 5 0 . 01) decreased during the anaesthesia. However, the red blood cell count, haemoglobin and packed cell volume values, and levels of total cholesterol, triglycerides, total protein and globulin were apparently not in¯uenced by the anaesthesia. In conclusion, we observed that the serum level of vitamin E and beta carotene were signi®cantly decreased, whereas serum MDA and vitamin A levels were signi®cantly increased during the en¯urane anaesthesia.