Effects of added dietary fat and protein on the growth and carcass characteristics of turkeys

Two experiments were conducted to quantitate the effects of several parameters on the growth, carcass characteristics and fat deposition of the turkey. In the first experiment, 0, 5, 10 or 15% fat from three sources (Fat 1, Fat 2 or Fat 3) was added to low (18%), standard (21%) or high (24%) protein diets fed to Nicholas Large White male turkeys from 8 to 22 weeks of age. Carcass quality as measured by fat deposition, carcass yield and breast meat yield was determined.

The addition of each 1% added fat up to 10% increased body weight gain .72%. Feed consumption decreased 1.3% and feed efficiency increased 2.3% for each 1% added fat up to 15%. Addition of Fat 2 to the diet resulted in significantly better feed efficiencies as compared with Fat 1 or Fat 3. The feeding of low protein diets as compared with standard protein diets decreased body weight gain, feed consumption and feed efficiency 13.2, 5.7 and 8.1%, respectively.

Addition of fat to the diet increased 22-week body weight and the amount of breast meat produced per kg feed consumed. For each 1% added fat to low and standard protein diets, leaf and gizzard fat deposition increased 10.2 and 8.0%, respectively. Feeding low protein diets resulted in a 10.4% decrease in body weight and a 19.5% decrease in breast meat yield. The increase in leaf and gizzard fat deposition from each 5% increment of added fat up to 10% was counteracted by a 3% increase in dietary protein.

In the second experiment, both sexes of the Nicholas Large White, Jaindl Large White and Jaindl Medium White strains were fed standard (21%) or high (24%) protein diets containing 0, 5 or 10% added dietary fat from 8 to 28 weeks of age. Carcass quality as measured by yield of carcass parts, fat deposition and the composition of breast meat was determined at 16, 20, 24 and 28 weeks of age.

The Nicholas strain of turkey had a greater growth rate and consumed less feed to reach heavier weights than the Jaindl Large strain. Addition of 10% fat to the diet decreased feed consumption 12% and increased feed efficiency 17%. Fresh carcass and breast meat yield increased with age of the turkey, indicating that marketing at younger ages does not take full advantage of the meat producing capability of the turkey. The Jaindl Large and Medium White strains averaged 6.8 and 6.9% more breast meat yield than the Nicholas strain. The Nicholas strain deposited 4.36 times more leaf fat and 1.84 times more lipid within the breast meat as compared to the Jaindl Large strain. Added dietary fat decreased fresh carcass yield .41% and breast meat yield .65%. Feeding high protein diets increased fresh carcass yield and breast meat yield .25 and .47%, respectively.