Digestion and absorption of fish oil by neonatal piglets

In order to establish the digestibility and absorption of fish oil, 18 unsuckled, newborn piglets were tube-fed an amount of fish oil calculated to provide the piglets' maintenance energy needs for 12 h. After fat administration the piglets were either intubated with 25 ml of fat-free milk replacer per h, or fasted. The digesta of the stomach, small intestine, and large intestine (digesta plus feces) were collected 12 h after fish oil intubation. Disappearance of total extractable fat was 95 +/- 1 and 94 +/- 1% for fed and fasted piglets, respectively. True absorption of the lipid was calculated from the disappearance of eicosapentaenoic acid and was 99% for both fed and fasted piglets. Nearly 50% of the stomach lipid was as diglycerides and free fatty acids, suggesting that hydrolysis of the fish oil was initiated in the stomach. Small intestinal lipid was 63-65% free fatty acids, indicating that the piglet pancreatic lipase was of sufficient activity to hydrolyze fish oil triglyceride. Neonatal piglets appeared to have ample capacity to digest and absorb fish oil, which supports the concept that lipid supplementation could improve the energy status of the newborn piglet.