Large Animal Surgery Resident Virginia Maryland College of Veterinary Medicine Blacksburg , Virginia
The Effects of Bit Chewing on Gastric Emptying and Orocecal Transit Times in Clinically Normal Horses. Byron C1, Andrews F2, Wong D3, Bogers SE1, Patton M1. 1Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA; 2Louisiana State University, School of Veterinary Medicine, Baton Rouge, LA; 3Iowa State University, College of Veterinary Medicine, Ames, IA.
Postoperative ileus is a common life-threatening problem of equids. Current treatments have questionable efficacy and high cost. Bit chewing, a form of sham feeding, decreases GI total transit time (TTT); however, the effect of bit chewing on gastric emptying time (GET) and small intestinal transit time (SITT) is unknown. Our objective is to determine whether bit chewing shortens GET, SITT, and total orocecal transit time (OCTT) in clinically normal horses. Our hypothesis is that bit chewing significantly decreases GET, SIT, and OCTT. Eight healthy horses underwent a prospective crossover design study. Video endoscopy (ALICAM) capsules were administered via nasogastric tube. Horses underwent experimental (bit chewing 20 minutes every six hours) or control (no bit) conditions in a randomized order with a minimum two-week washout period between trials. Video capsules were recovered from manure and GET, SITT, and OCTT were determined from videos. Horses under bit chewing conditions had significantly shorter overall OCTT compared to control (no bit) conditions. Mean (median) times for bit chewing conditions were: GET 2.39 h (1.84 h), SITT 3.17 h (3.35 h), and OCTT 6.53 h (5.98 h). Mean (median) times for control conditions were: GET: 4.13 h (4.03 h), SITT 4.33 h (4.4 h), and OCTT 8.61 h (9.01 h). Results suggest that bit chewing decreased gastric and small intestinal transit times. Limitations included a small sample size and incomplete retrieval of all ALICAM capsules. Bit chewing may be a safe and inexpensive intervention for ileus, and further investigation in clinical patients is warranted.