Effect of dietary vitamin C addition on performance, plasma vitamin C and hematic iron status in weanling pigs

Each of 64 pigs weaned between 4 and 5 weeks of age was fed ad libitum one of four diets: (1) a basal 18% crude protein, corn-soybean meal-oats-dried whey starter diet or (2,3,4) the basal diet supplemented with 330, 660 or 990 ppm L-ascorbic acid (vitamin C). The pigs were kept in groups of four and housed in an environmentally regulated nursery with a raised, expanded metal floor. The room temperature was maintained at 21 C and floor allowance was .54 m2/pig. After 28 days, dietary vitamin C supplementation had improved daily weight gain and daily feed intake of pigs without altering gain to feed ratio. Plasma vitamin C concentration decreased during the 4 weeks period after weaning in pigs not fed supplemental vitamin C but not in those fed supplemental vitamin C. Plasma Fe was reduced at day 28 in pigs given supplemental vitamin C. Simple correlation indicated a positive (P less than .05) relationship between plasma vitamin C concentration and weight gain and a negative (P less than .05) relationship between plasma vitamin C and plasma Fe concentration. Results obtained suggest that, under the experimental conditions, young pigs weaned between 4 and 5 weeks of age require dietary vitamin C supplementation for maximum weight gain and that the benefit of vitamin C addition may be related to Fe metabolism.