|Owens, Lisa - BAYLOR COLL MEDICINE|
|Berseth, Carol - BAYLOR COLL MEDICINE|
Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 21, 2002
Publication Date: August 1, 2002
Citation: OWENS, L., BURRIN, D.G., BERSETH, C.L. MINIMAL ENTERAL FEEDING INDUCES MATURATION OF INTESTINAL MOTOR FUNCTION BUT NOT MUCOSAL GROWTH IN NEONATAL DOGS. JOURNAL OF NUTRITION. 2002. v. 132. p. 2717-2722. Interpretive Summary: The aim of this study was to determine how relative amounts of nutrition fed to neonatal pups affected intestinal function and growth. The specific intestinal function we examined was motility, which is the mechanical process that moves food through the gut. In premature infants, this process has been shown to be poorly developed and prevents these infants from feeding normally. This process delays their development and prolongs the duration of their hospital stay, both are undesirable outcomes. To address this question, we studied newborn dogs because they have a very similar pattern of intestinal motility to that of human infants. We fed the pups increasing amount of food via the gut (enteral feeding) and maintained their total nutrient intake by infusing the remaining nutrients via a tube in their blood vessels, also called parenteral nutrition. We examined seven different levels of enteral feeding between 0 and 100% and fed the pups these diets for four to five days. After the dietary treatment period, we measured their intestinal motility and the size of their intestine. We found that the level of enteral nutrition needed to stimulate intestinal motility was much lower than that needed to stimulate intestinal growth. We also found that the minimal amount of enteral nutrition needed to stimulate intestinal growth was 30% of the total nutrient intake, consistent with previous studies in piglets. The results of this study suggest that doctors only need to feed very small amounts of food enterally, less than 10% of the total nutrient intake, in order to stimulate development of intestinal motility. In addition, the study indicates that the amount of food necessary to stimulate intestinal motility does not also stimulate intestinal growth.
Technical Abstract: Providing small enteral feedings for parenterally fed preterm infants during the first few weeks of life improves feeding tolerance. However, it is not known whether these feedings achieve this result via stimulation of gut growth and/or maturation of function. The minimal level needed to attain these responses is also critical to identify, because neonatologists often limit feeding volumes to minimize the risk of necrotizing enterocolitis. Thus, we determined the dose-response relationships between enteral feeding volume and gastrointestinal growth and small intestine motor function. Newborn canine pups (n = 51) received 0, 2.5, 5.0, 7.5, 10, 30 or 100% of their daily fluid intake enterally with the remainder given parenterally for 4-5 d. Motor activity was recorded, blood drawn for determination of gastrin and motilin, and intestinal tissue harvested for determination of DNA and protein content and morphology. Feeding volumes that provided 30% or more of daily fluid intake significantly increased small intestinal mucosal growth above that of unfed pups, but feeding volumes that provided as little as 10% of daily fluid intake significantly induced maturation of motor patterns beyond that of unfed pups. Plasma concentrations of gastrin and motilin did not differ among groups. We conclude that small enteral feedings typically used for minimal enteral feeding strategies improve feeding tolerance by triggering maturation of motor function but not gut growth in neonatal dogs. Small feeding volumes trigger this maturation as well as large volumes.