Abstract Bovine milk co-products are included at relatively high levels in nursery pig diets to ease the transition from porcine milk to solid feeds. Compared to porcine milk, bovine milk has decreased concentrations of key milk oligosaccharides that provide prebiotic benefits. Particularly, galacto-oligosaccharides (GOS) and 2’-fucosyllactose (FL), are relatively lacking in bovine milk compared to porcine milk. Therefore, supplementing bovine milk co-products with GOS or FL could support intestinal health and thus enhance growth of nursery pigs. This study investigated the effects of increasing levels of GOS or FL on intestinal health and growth performance of nursery pigs. Forty pigs (6.8 ± 0.2 kg body weight) weaned at 3 weeks-of-age were allotted into dietary treatments using a randomized complete block design. Treatments were 3 levels of GOS at 0.0, 1.5, and 2.3% and 3 levels of FL at 0.0, 0.2 and 0.3% by supplementing GOS or FL to a common basal diet. Pigs were fed for 21 d in 2 phases. Growth performance was evaluated throughout, and on d 21, pigs were euthanized for collection of jejunal mucosa and tissue. Data were analyzed using the PROC RSREG of SAS to determine the linear effects of increasing GOS or FL levels, respectively, on the measured parameters. Increasing levels of GOS or FL linearly decreased (P 0.05) the Shannon and Simpson indices of the jejunal mucosa. Increasing levels of GOS or FL tended to linearly decrease (P = 0.051 and 0.076, respectively) the expression of toll-like receptor 4 in the jejunum. Increasing levels of GOS tended to linearly decrease (P = 0.082) and increasing levels of FL linearly decreased (P 0.05) the expression of cluster of differentiation 14 in the jejunum. Increasing levels of GOS or FL linearly increased (P 0.05) and tended to linearly increase (P = 0.060) the jejunal crypt depth, respectively. Increasing levels of GOS or FL linearly decreased (P 0.05) the jejunal villus height to crypt depth ratio. Increasing levels of GOS tended to linearly decrease (P = 0.061) the percentage of Ki-67 proliferative cells in the crypt. Increasing levels of FL linearly increased (P 0.05) the Ki-67 proliferative cell count in the jejunal crypt. Increasing GOS levels tended to linearly increase (P = 0.098) average daily gain without effects from increasing FL levels. It is assumed that an extended feeding period may be needed for growth response. In conclusion, increasing levels of GOS or FL altered jejunal microbiota diversity and reduced expression of genes related to inflammation in the jejunum of nursery pigs with growth advantage from GOS. These effects highlight the potential uses of milk oligosaccharides to enhahce the intestinal health and growth of nursery pigs fed diets including bovine milk co-products.
Gormley et al. (Wed,) studied this question.