Transgenic mice are a powerful and much used tool in the field of feeding behavior. However, much of the biobehavioral characterization of the controls of feeding has been done in rats. The present presentation describes our efforts to adapt techniques traditionally used in rats to the analysis of feeding behavior in mice. This has been done within Smith's theoretical framework of positive and negative feedback controls of meal size. We show that mice are sensitive to increases and decreases of post-ingestive negative feedback, as they reduce intake in response to intragastric nutrient preloads and CCK, while they increase their intake in a sham-feeding preparation. Finally, we discuss our initial attempts to characterize the controls of feeding in a transgenic mouse model, the NSE-RB mouse.