Effect of dietary high oleic acid sunflower oil, copper and vitamin E on the quality of pork from pigs slaughtered at 160 kg live weight

On a set of 84 Large White gilts, reared from 35 to 160 kg live weight, sev en dietary treatments were compared: Control diet, supplemented with 30 mg/ kg Cu, but with no added E and diets containing 6% high-oleic acid sunflowe r oil (oil diets), supplemented with 30 or 170 mg/kg Cu both crossed with e ither 0 or 100 or 200 mg/kg added vitamin E. Growth parameters were not aff ected by the diet. Dietary oil addition increased the proportion of oleic a cid in backfat and lipids from loin muscle, affected the calculated iodine number of the backfat (>70 in oil fed groups), but not firmness; the oleic acid in backfat slightly increased with dietary copper addition. In oil die ts, the value of thiobarbituric acid-reactive substances of pork 6 d after slaughtering was 42% lower than that in control pigs. Scant effects on pH(4 5), pH(u), color and drip losses were observed. The oleic acid content can be safely increased in diets of heavy pig for fresh pork. No advantage was obtained with 170 mg/kg copper addition nor with vitamin E addition to a 6% high-oleic acid sunflower oil diet.