Influence of Dietary Protein and Energy on Performance and Carcass Composition of Heavy Turkeys

Abstract Four levels of dietary protein, (32, 28, 24, and 20%) were fed to heavy weight male and female turkeys. These protein levels were reduced by 3% at 4, 8, 12, and 16 weeks of age. All diets within an age group were similar in energy. A second trial involved the feeding of four different dietary energy levels (3300, 3100, 2900, and 2700 kcal metabolizable energy/kg) with protein constant within an age group but reduced by 4% at 4, 8, 12, and 16 weeks. The males were fed to 20 and the females to 16 weeks of age. In Trial 1, the lowest protein series did not support optimum weight gain for either sex. However, the three higher protein regimens resulted in similar weight gain and feed:gain ratios at market age except that the 24% protein diet series was inferior for the males at 20 weeks. In Trial 2, weight gain was superior for both sexes with the 2700 and 2900 kcal diet series compared with the higher energy diets; however, the reverse was true for feed:gain ratio. Dietary protein and energy level had little influence on carcass yield or on the yield and composition of edible meat. Increasing dietary protein resulted in a decrease in the efficiency of dietary protein to edible protein yield.