Chemical senses involved in garter snake prey training

Trained 8 garter snakes to follow earthworm-extract trails in a multiple-choice maze and then subjected them to either sham surgery or complete bilateral vomeronasal nerve transection. Ss with sham surgery trailed and ate at preoperative levels; Ss lacking a functional vomeronasal system developed a feeding deficit and trailed at chance levels. In Exp II 16 Ss were preoperatively tested for ability to follow a battery of trails including a range of trail concentrations and 2 trail manipulations. After baseline testing, 2 Ss were subjected to sham surgery, 7 to olfactory nerve transection, and 7 to vomeronasal nerve transection. Ss with vomeronasal nerve lesions demonstrated trailing and feeding deficits commensurate with the extent of nerve damage. Ss with olfactory nerve cut and sham surgery followed all trails at preoperative levels and maintained high tongue-flick rates when following stronger extract trails. Four Ss (2 with sham lesions, 1 with olfactory nerve lesion, and 1 with a partial vomeronasal nerve lesion) were tested with the vomeronasal ducts sutured closed. These Ss were unable to follow any trails at better than chance levels, but most continued to attack and ingest earthworm bits. Results suggest that garter snakes are heavily dependent on the vomeronasal system for following chemical prey trails. (43 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).