Influence of galactosyl lactose on energy and protein digestibility, enteric microflora, and performance of weanling pigs.

In three experiments, weanling pigs were used to investigate the effect of feeding .5% galactosyl lactose in a simple corn-soy diet on nutrient digestibility, selected ileal microbial concentrations, fermentation acids, and performance. In Exp. 1, 20 21-d-old weaned pigs in two replicate trials were fed either a 19% CP corn and soybean meal diet or a similar diet containing .5% galactosyl lactose. Feces and urine were collected over a 3-wk period to determine apparent CP and energy digestibilities. Apparent digestibilities of CP and energy were not different between treatments. In Exp. 2, 24 14-d-old nursing pigs were cannulated at the terminal ileum and fed the diets described above after weaning at 21 d of age. Ileal samples were collected at 20, 23, 27, 30, 34, 37, and 41 d of age. Samples were assayed for VFA, lactate, and selected microflora. Ileal fermentation acid concentrations and selected microflora were affected by age of pig but were not different between feed treatments. In Exp. 3, 91 21- to 24-d-old weaned pigs were fed the control and test diets already described; intake, BW gain, and feed efficiency were determined for 9 wk after weaning. Intake was greater in pigs fed galactosyl lactose, but ADG and gain/feed did not differ between treatments. Inclusion of galactosyl lactose in weanling pig diets did not affect protein or energy digestibility, microflora, short-chain fatty acids, or performance of young pigs.