Effect of enteral calorie/nitrogen ratios on weight gain and liver function and morphology in rats

Seventy-five Simonson albino male rates, each weighing 200-300 grams, were randomly divided into five groups of fifteen rats each. Group I, the controls, received rat chow which provided a calorie/nitrogen ratio of 95 Kcal/gram/nitrogen. Animals in Groups II to V received an elemental diet with calorie/nitrogen ratios of 100, 150, 300 and 450 Kcal/gram/nitrogen each, respectively. During the 30-day experimental period, daily calorie intakes were recorded and the rats were weighed every third day. Pre- and post-treatment hepatic function and fatty infiltration were analyzed and compared. The animals treated with a calorie/nitrogen ratio of 100-150 calories/gram of nitrogen had a statistically significant better weight gain with less fatty infiltration of the liver when compared to the other groups. This study supports the clinical impression that administration of lower calorie/nitrogen ratios is associated with a better weight gain.