Studies on Intermittent Supplementation

Abstract

Two lots of weanling Sprague-Dawley rats were fed, for 30 days, diets at 10 and 14% protein content. Each lot consisted of 4 groups fed on: (a) a gluten diet; (b) a gluten diet continuously supplemented with casein; (c) a gluten diet on odd days, and a gluten diet supplemented with casein, ad libitum, on even days; (d) a gluten diet on odd days and a pair-fed gluten diet supplemented with casein on even days. Growth-curves, PER, NPU, NGI, and carcass and liver composition have been studied. The results show that the recovery rate in the days of supplementation is dependent on the level of nitrogen intake rather than on the balance occurring between non-supplemented and supplemented diets, according to whether the latter is offered ad libitum or pair-fed. At the cellular level, the count of nuclei and the DNA-P/nucleus content in liver cells show that in groups at lower protein intake, the different ways of supplementation affect cellular maturation, while in groups with higher protein intake it is cellular multiplication that is affected.