Variation in consumption and catch‐up growth following protein malnutrition

Catch‐up growth rates, after a period of protein malnutrition, will vary with timing of insult and rehabilitation, as well as sex. Understanding changing patterns of post‐insult consumption related to the timing of rehabilitation can provide insight into differences of such growth rates. We hypothesize that higher catchup growth rates will be correlated with increased food consumption, and explain differences between the sexes in such rates. To determine this, we measured total food consumption, protein consumption and body mass following an increase of dietary protein (from 4.6% to 27.6%) at 40, 60 and 90 days, with two control groups ( Rattus norvegicus ) that received either 4.6% or 27.6% protein for 350+ days. Immediately following rehabilitation, rats' food consumption decreased significantly, although re‐nourishment at ages 40 or 60d resulted in an immediate increase in body mass. The duration of protein restriction affected consumption: rats rehabilitated at younger ages consumed more following re‐alimentation than those re‐nourished at older ages. A nimals chronically fed 4.6% & 27.6% protein diets, consumed the same quantity of food per body mass. While rehabilitated animals did compensate with greater food consumption, variable responses in animals of different ages and sex may explain an aspect of the dynamics of catch‐up growth. Funding: Wendell‐Weiman Fund, U of Cincinnati