The ontogeny of feeding in rats: II. Independent ingestive behavior.

Abstract

Rat pups 3 days of age and older consumed large quantities of milk, sucrose and wet mash when they were placed in warm containers in which 1 of these diets was spread on the floor. The volume of pups'' intake was directly related to the severity of food deprivation. Ingestive behavior occurred in the early part of the 30 min test; later in the test, pups stopped feeding and became quiescent. Their ingestive behavior thus resembled that of adult rats in the motor aspects of feeding responses (licking and lapping), the dependency on deprivation for intake and the pattern of intake termination. When diet was restricted to a small area of the test container, young pups consumed little diet. They did not appear able to direct or focus their ingestive responding. It was not until 9-12 days of age that pups successfully consumed milk from a localized source.