Parameters of the meal pattern in rats: their assessment and physiological significance.

Parameters of the meal pattern in rats were assessed and their physiological significance investigated through a detailed study of continuous graphic recordings over 20 consecutive days in ten rats. Both prandial and diurnal periodicities were examined. The definition of meals, by a criterion of 40 min of non-eating before and after a feeding episode, was validated statistically. The two superimposed periodicities were substantiated by studying night and daytime differences in meal sizes, meal-to-meal intervals, meal size/interval ratios, and post prandial correlations. The results provide new evidence for the role of metabolic and neuroendocrine factors in determining the relationships between meal size and post-meal intervals and their differences during the two parts of the diurnal cycle.