One experiment was carried out to evaluate the use of lactose sources (dried whey and lactose) and lysine levels (1.20 and 1.50%) in diets for weaned piglets with diferent body weight at 21 days of age, regarding performance and intestinal morphology of piglets in initial phase. Three hundred and eighty-four piglets from 21 to 42 days were sorted in a complete randomized design with a 2 x 2 x 2 factorial arrangement, in a total of eight treatments and four replications each. Samples of duodenum from three piglets slaughtered at 42 days of age were harvested from each treatment to study intestinal morphology. The following performance characteristics were evaluated: weight gain, feed intake and feed conversion. The morphologycal parameters were as follows: villous height, duodenum crypt depth, villous height/duodenum crypt depth ratio and pancreas/carcass weight ratio. Performance of piglets fed corn-soybean meal- based diets with lactose was better when the level of lysine was of 1.5%. It was also concluded that the type of diets studied did not alter the morphologycal parameters and that the villous height is a direct function of piglet weight.
dried whey; lactose; lysine; piglets
