EFFECT OF VITAMIN-E INJECTION ON CORTISOL AND WHITE BLOOD-CELL RESPONSE TO SURGICAL STRESS IN DAIRY-COWS

In 20 dairy cows the effect of a single vitamin E injection on cortiso l and white blood cell response to surgical stress was investigated. A bdominal surgery (omentopexy) was carried out in order to correct a le ft abomasal displacement. Ten hours prior to surgery 10 cows were inje cted intramuscularly with 10 mg DL-alpha-tocopheryl acetate per kg bod y weight. Ten cows (controls) received art equivalent volume of inject able water Over a 72 hour period plasma samples were collected. In 8 c ows (4 cows from each group) alpha-tocopherol in liver tissue was dete rmined. Plasma vitamin E concentrations were significantly higher in v itamin E injected cows than in controls in all of the samples after th e vitamin E injections. Similarly, liver alpha-tocopherol concentratio ns were significantly higher in vitamin E injected cows than in contro ls. The surgical stress fed to profoundly increased plasma cortisol le vels and leucocytosis due to neutrophilia within 5 hours after the sur gery. Plasma cortisol levels as well as leucocyte counts were not affe cted by route of vitamin E administration used.