Feeding pattern in Peromyscus maniculatus: the response to periodic food deprivation

The prairie deermouse (Peromyscus maniculatus bairdi) is strongly nocturnal on a 12:12 LD-cycle with a bimodal, dusk-dawn feeding pattern. It has been suggested for the rat that the dusk peak is more dependent on the animal's immediate energy needs while the dawn peak has an anticipatory function in storing food. The present study investigates this pattern in terms of the feeding response of deermice following periodic food deprivation. It was found that the response is not uniform within the D-phase; survivability, food intake, and maintenance of body mass were all favored by access to food during the final six hours vs the initial six hours. Deprivation experience enhanced survivability with the early-food, presumably through a reduction in locomotor activity and not by increased food intake. These results suggest a rigid temporal organization of feeding behaviors whereby early-night foraging and hoarding are necessary in allowing for late-night filling in anticipation of the L-phase.