|Burrin, Douglas - Doug|
Submitted to: British Journal of Nutrition
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/6/2006
Publication Date: 6/1/2006
Citation: Thymann, T., Burrin, D.G., Tappenden, K.A., Bjornvad, C.R., Jensen, S.K., Sangild, P.T. 2006. Formula-feeding reduces lactose digestive capacity in neonatal pigs. British Journal of Nutrition. 95:1075-1081. Interpretive Summary: Clinical studies of preterm infants suggest that their ability to digest lactose, the major milk sugar, is incomplete and represents a loss in their dietary energy intake. The incomplete lactose digestion in preterm infants has been ascribed to insufficient lactase expression, the enzyme that breaks down lactose, and some have linked poor lactose digestion to the risk of necrotizing enterocolitis, a devastating infant disease. Many preterm infants are fed formula rather than mother's breast milk, and it is conceivable that formula lacks the key ingredients necessary to maintain intestinal lactose digestive function. The current study was designed to test whether feeding formula compared to breast milk, called colostrum, affects the ability of newborn piglets to digest lactose. Newborn piglets were used as a model of premature infants. The results indicate that piglets allowed to either breast-feed or were tube-fed formula or colostrum all had a similar stimulation of intestinal growth. However, piglets fed formula had a significantly lower capacity to digest lactose and absorb glucose compared to both breast-fed and colostrum tube-fed piglets. These studies suggest that components of colostrum are necessary to maintain optimum intestinal lactose digestion in newborn piglets and that formula feeding may cause lactose malabsorption. The findings provide further support for the recommendation to feed premature infants breast milk after birth.
Technical Abstract: The intestine of newborn pigs develops rapidly during the first days postpartum. We investigated if feeding milk replacer (infant formula) as an alternative to colostrum has compromising effects on nutrient digestive function in the neonatal period. Nineteen piglets born at term were assigned to one of four treatments: (1) newborn controls; (2) natural suckling for 24 h; (3) tube-fed formula for 24 h; (4) tube-fed porcine colostrum for 24 h. All three fed groups showed significant increases in small-intestinal and colonic weights, villous heights and widths, maltase and aminopeptidase A activities, and decreases in dipeptidylpeptidase IV activity, relative to newborn pigs. Following oral boluses of mannitol, lactose or galactose, formula-fed pigs showed significantly reduced plasma levels of mannitol and galactose compared with colostrum-fed pigs. Activity of intestinal inducible NO synthase and plasma levels of cortisol were significantly increased, whereas intestinal constitutive NO synthase and alpha-tocopherol were decreased in formula-fed pigs compared with colostrum-fed pigs. Although formula-fed pigs only showed minor clinical signs of intestinal dysfunction and showed similar intestinal trophic responses just after birth, as those fed colostrum, lactose digestive capacity was markedly reduced. We conclude that formula-feeding may exert detrimental effects on intestinal function in neonates. Formula-induced subclinical malfunction of the gut in pigs born at term was associated with altered NO synthase activity and antioxidative capacity.