Laparoscopic abomasal cannulation in sheep

Abomasal cannulation, an important research tool in experimental procedures, provides a method for the placement of an abomasal cannula in sheep. The aim of this study was to describe a technique for laparoscopic abomasal cannulation in sheep. It was performed in six anaesthetised sheep positioned in dorsal recumbency using three portals in the abdomen. The first absorbable traction suture was placed 1 cm cranial to the determined abomasal cannula site. A stab incision was made with a laparoscopic monopolar hook electrode in the middle of a purse-string suture placed around the abomasal cannula site. The T-shaped cannula was inserted into the abomasum lumen through the stab incision, and the second traction suture was then placed 1 cm caudal to the abomasal cannula site. The T-shaped abomasal cannula was pulled out of the abdominal cavity through the exit wound located 3-5 cm lateral and 10-12 cm cranial to the right side of the umbilicus. The two traction sutures were tied. The T-shaped cannula was secured to the skin with a finger-trap suture. Repeat laparoscopy was performed 1 month later. Firm adhesion between the abomasum and abdominal wall was observed in all sheep, with no evidence of leakage or peritonitis. No major intraoperative or postoperative complications were encountered. The median surgical time was 49 min, with a range from 42 to 58 min. The abomasal contents were collected easily. In conclusion, laparoscopic abomasal cannulation is safe and easy to perform. Its low complication rates and the "ideal" placement of the tube into the abomasum make it an especially attractive alternative to traditional surgical abomasal cannulation in veterinary practice.