Olfactory bulbectomy in rats modulates feeding pattern but not total food intake

The role of olfactory input in the regulation of food intake and feeding patterns in rats was investigated by performing bilateral olfactory bulbectomy. Compared to control rats, bulbectomized rats ate the same amounts of food, but did so via a decrease in meal size, and a doubling in meal number. Although no increase in meal duration occurred, the exploratory behavior of sniffing during meals and between meals also increased significantly. While it is not yet clear how the olfactory bulbs participate in regulating food intake configuration resulting in changed feeding patterns, their clinical role can be appreciated by observing the acute changes in feeding pattern that occur when their input to the lateral hypothalamic area is damaged experimentally.