Prandial drinking and the disruption of meal patterns in olfactory bulbectomized rats

In order to determine the cause of the disrupted feeding pattern in bulbectomized and recovered LH lesioned rats and to study the role of prandial drinking in producing this feeding pattern, feeding and drinking patterns were simultaneously recorded in these lesioned preparations. It was found that in normal rats drinking occurred mainly before and after the meals. In bulbectomized rats, drinking occurred also before and after the meal, but the main part of the meal associated takes place during the numerous short pauses within the meal. In LH recovered rats the meal associated drinking occurred in a very rapid alternation between eating and drinking during feeding bouts (prandial drinking) and not during the meal pauses. It is suggested that the nibbling pattern seen in LH recovered rats as well as in bulbectomized rats is not due to the prandial drinking but results from the loss of an olfactory input to the LH area.