A new apparatus for the continuous infusion-feeding of unrestrained dogs is described. The swivel we designed, like the whole apparatus, is quite simple but has proven to be totally effective inasmuch as it needs no day-to-day care. The system has been satisfactorily used for jejunal feeding for periods of up to 33 days. Dogs were very easily acclimatized to this apparatus; the majority of animals lost weight at the beginning of enteral feeding but recovered their body weight after 19 days if a daily caloric intake fixed at a minimum of 100 kcal/kg body weight was provided. The mechanical complications secondary to catheterization of the gastrointestinal tract can be abolished by anchoring the vinyl tube to the intestinal wall. The dog appeared to be an excellent species for long-term experiments as little attention was required during the infusion period; because general adaptation to Isocal was good, feeding hypercaloric amounts of diet was unnecessary to sustain adequate body weight. This model was found to be well suited for the surgical and feeding techniques required for a long-term study of enteral nutrition.