Mice, with the variety of genotypes they provide, should be particularly useful for studies of growth factors and gene products in regeneration of autonomic pathways such as the vagus nerve. To provide a foundation for examinations of mouse vagal reorganization, two experiments assessed the rate, extent, and accuracy of afferent reinnervation of the stomach after vagotomy and related these patterns to feeding behavior. Experiment 1 characterized the pattern of afferent regrowth into the gut after unilateral truncal vagotomy by labeling these afferents with WGA-HRP and Micro-Ruby. Regenerating neurites had reached and in some cases already reinnervated the stomach by 4 weeks post-axotomy. By 8 weeks, regrowth was more extensive, and many fibers had redifferentiated terminals in the smooth muscle. By 16 weeks, vagal projections had reached or exceeded normal density in the corpus, with still reduced densities in the forestomach, and a minimum of regrowth in the antrum. At all time points, not only appropriate terminals, but also growth cones and aberrant endings, were observed. Experiment 2 evaluated meal patterns of vagotomized mice, using a solid diet, over the period of regeneration; the experiment also evaluated CCK suppression of a liquid meal after unilateral and bilateral truncal vagotomies. Animals with unilateral vagotomies as well as those with bilateral vagotomies ate smaller and more frequent meals. These disturbed patterns became more pronounced in the first 8 weeks after vagotomy, during the period in which regeneration was occurring. CCK inhibition of intake was attenuated by bilateral, but not unilateral, vagotomy. Overall, the spatial and temporal patterns of structural and functional changes observed during regeneration verify that the mouse provides a useful preparation for examining the control of vagal plasticity.