Effect of oral formula ±igf-i on intestinal growth and enzyme activity of piglets on total parenteral nutrition (TPN)

TPN is commonly used for the nutritional support of prêtent! infants; however, TPN leads to GI atrophy which further compromises GI function. To ease the transition to oral feedings, infants on TPN are often fed small volumes of formula to promote GI function. Herein, the potential benefits of adding insulin-like growth factor-I (IGF-I) to formula were assessed. Piglets (d 1 postpartum) were fitted with aortic catheters via the umbilical artery. A nutritionally complete TPN solution (215 kcals/kg/d; 17.3 g protein/kg/d; 50% dextrose and 50% lipid non-protein kcals) was infused for 7 d. TPN piglets were gavaged twice daily with 4 mL of sterile water, formula, or formula+1000 ng/mL IGF-I. Littermate piglets fed formula served as oralfed controls. Final body weight of TPN piglets (2.3±0.2 kg) was comparable to oral fed piglets (2.7±0.5 kg), however, stomach, pancreas, liver and kidney weight (g/kg) were reduced in the TPN piglets relative to oral fed. Intestinal length (170.3±2.7 cm/kg) and weight (21.6±3.8 g/kg) of TPN piglets were 99% and 51% of control, respectively. Intestinal weight and length were similar among the TPN groups. Lactase specific activity (SA) was elevated in TPN-fed piglets compared to oral-fed and did not differ among the TPN groups. In contrast to lactase SA, sucrase SA was reduced in TPN piglets relative to oral-fed. Sucrase SA tended to be higher in TPN piglets given formula+IGF-I compared to formula alone. The lack of effect of oral feeding on GI growth may be due to the small amount of formula used (-1% of oral-fed piglets) and consequently IGF-I dose (-4.3 ng IGF-I/kg/d) received by the piglets. (Supported by HD-29264).