ON THE UTILIZATION, RETENTION AND STATUS OF VITAMIN-E IN MINK (MUSTELA-VISON) UNDER DIETARY OXIDATIVE STRESS

Sixteen male scanblack mink kits were challenged for a period of 8 weeks with a diet containing high levels of dietary PUFA (25% of dietary fat, peroxide value: 473 mequ O2/kg fat) derived from whole minced mackerel. The selenium content of the experimental diet was sufficient (0.33 ppm). After intake of increasing amounts of dl-alpha-tocopheryl acetate (0, 14.3, 28.6 and 57.2 mg/mJ ME) the apparent digestibility, retention as well as status of vitamin E were determined. The apparent digestibility of alpha-tocopherol decreased from 77% to 60% with increasing dietary alpha- tocopherol concentrations from 14.3 to 57.2 mg/MJ ME. In vitamin E deficient group the dietary treatment resulted in steatosis rather than in myodegeneration, degeneration of the myocardium and sudden death. The results obtained from this study lead to the conclusion, that mink are quite resistent to dietary oxidative stress. Vitamin E concentrations of 14.3 mg/MJ ME corresponding to 83 mg dl-alpha-tocopheryl acetate/kg diet were adequate in order to prevent all signs of steatosis. This fact indicates that the allowances for vitamin E supplementation in mink under practical feeding conditions are sufficient.