TECHNIQUE FOR CREATING A PERMANENT CECAL FISTULA IN THE RAT

A method was developed to surgically implant a silicone/stainless stee l fistula-cannula in the cecum of freely moving rats. The specially de signed fistula-cannula allows sampling of cecal contents at any time w ithout disturbing the physiologic functions of the intestinal tract, a s evaluated by observation of general wellbeing and postmortem macrosc opic inspection. The fistula-cannula was implanted in 12 male rats und er general anesthesia. The animals remained in good health during the postoperative period lasting up to 9 weeks. They gained weight normall y compared with a control group (n = 8) that had not undergone surgery . Samples of 0.2 to 1.0 g of contents could be collected with a micros patula, without the need to anesthetize the animal. The model provides a useful system for sampling cecal contents without the need to sacri fice the animal. Because it allows cross over studies to be carried ou t, this approach may result in significantly reducing the number of an imals required for digestive studies.