Effects of protein level and enzyme supplementation upon growth and rate of digesta passage of male turkeys.

An experiment was conducted to determine the effect of feeding enzyme supplements (Avizyme and protease) at two levels of dietary crude protein (24 and 28%) to male turkeys from 0 to 5 wk of age. The Avizyme-protease enzyme mixture was fed at five concentrations within each protein level in an effort to determine an optimal level of supplementation. Enzymes were added to the 24% protein diet to determine whether the supplements would enhance the growth performance of birds fed the lower protein diet to the level of those fed the 28% protein diet. Rate of passage was evaluated to determine whether an ANF effect corresponded to enzyme concentration or protein level. Dietary protein level significantly influenced growth. Birds fed the 28% protein diet had improved body weight gain, feed consumption, and feed efficiency of 11.5, 6.5, and 4.4%, respectively, when compared with birds fed the 24% protein diet. Enzyme addition to the 24% protein corn-soybean meal diet produced a graded response but did not improve growth over the control. Although enzyme supplementation improved poult utilization of the 24% protein diet, growth and feed utilization were not equal to the performance of the poults fed the 28% protein diet. When the enzyme mixture was added to the 28% diet, performance was not consistently altered. Rate of digesta passage was not different between the levels of dietary protein or among levels of enzyme supplementation, indicating that the applied protein levels did not deleteriously affect nutrient utilization.