EFFECT OF FEEDING A MILK REPLACER TO EARLY-WEANED PIGS ON GROWTH, BODY-COMPOSITION, AND SMALL-INTESTINAL MORPHOLOGY, COMPARED WITH SUCKLED LITTERMATES

Feeding of milk replacer to early-weaned pigs was evaluated in two exp eriments. In Exp. 1, 18 litters of pigs were either weaned conventiona lly (d 21), split-weaned and fed milk replacer plus starter diet (d 14 and 21), or weaned and fed milk replacer plus starter diet (d 21). Sp lit weaning combined with feeding a milk replacer increased ADG 22% fr om d 14 and d 28 compared to conventional weaning (P <.05). Feeding a milk replacer plus starter diet after weaning increased ADG 30% betwee n d 21 and 28 compared to conventional weaning (P <.01). In Experiment 2, four litters of 12 pigs each were divided at d 18 into six heavy a nd six light pigs and randomized across sow-suckled milk replacer, or starter diet groups. After 1 wk, pigs fed milk replacer weighed 20% mo re (P <.001), contained 10% more protein (P <.01) and 17% more fat (P <.05), and had 74% longer villi in the proximal small intestine (P <.0 01) than suckled pigs. In contrast, pigs fed starter diet weighed 19% less (P <.001), contained 20% less protein and fat (P <.001), and had 28% shorter villi in the proximal small intestine(P <.05) than suckled pigs. Therefore, milk replacer feeding the 1st wk after meaning stimu lates pig development, both locally in the small intestine and on a wh ale-body basis, most likely by an increased energy and nutrient intake . Suckling beyond 18 d postnatally inhibits pigs to reach maximal pote ntial weight gain. In conclusion, milk replacer feeding might be benef icial to reach maximal pig weight gain at weaning.