Abstract
1. A feeding trial has been carried out with sixty-four individually fed Large White pigs offered eight different diets prepared at four energy levels and two levels of crude protein. A record was maintained of the rate of live-weight gain and food was given at a defined restricted level. Carcass quality was assessed by a procedure of complete dissection into visible fat, lean, etc. 2. Though differences in the rates of live-weight gain and food conversion efficiency were not statistically significant, the best performance was recorded when the diets contained 16 % crude protein and yielded the equivalent of 2950 kcal. digestible energy per kg. upon oxidation. The energy: lysine ratio (kcal. digestible energy per kg. per unit percentage lysine in the ration) was approximately 3500.