Net Protein Utilization of Stock Diets for Rats and Mice

Male Sprague-Dawley rats of six weeks of age were fed on ten percent crude protein diets for a ten day experimental period. The net protein utilization (NPU) by carcass analysis of six kinds of revised stock diets for rats and mice was compared with that of purified whole-egg protein and milk casein. NPU values for all revised stock diets and milk casein were lower than those for purified whole-egg protein. Compared to milk casein, two kinds of revised stock diets showed lower NPU, but the remaining four diets had similar NPU.