Effect of Early Protein and Energy Restriction of Large Turkey Toms Fed High-Fat or Low-Fat Realimentation Diets.: 1. Performance Characteristics

Abstract

The effect of early protein and energy restriction on the performance of large turkey toms fed a high or low fat realimentation diet was studied. Two levels of protein [100% (HP) and 70% (LP) of 1984 National Research Council (NRC) recommendations] were available ad libitum in a factorial arrangement with two levels of energy [100% (HE) and 90% (LE) of 1984 NRC reference level] to Nicholas toms from 10 days to 6 wk of age. Subsequently, the four treatment groups were fed diets containing either 4 or 8% fat; other nutrients were kept consistent with 1984 NRC recommendations until the toms were 20 wk of age. The LP or LE diets reduced weight gain (WG) and increased feed:gain (F:G) ratio from 10 days to 6 wk of age (P<.005). Feeding LP diets significantly reduced protein consumption per unit gain and increased energy consumption per unit per gain, but the converse was observed with LE. In contrast to toms fed the HP diets, those fed the LP diets from 6 to 20 wk of age were consistently lighter in 20-wk body weight (14.1 kg versus 14.6 kg, P<.005) and had a lower F:G ratio (2.96 versus 3.04, P<.005). Toms fed the LE diets were lighter than those fed HE diets until 18 wk (P<.05), and they had a lower F:G ratio (2.97 versus 3.03, P<.05) from 6 to 20 wk of age. Supplemental fat increased WG and decreased F:G ratio during realimentation, but interaction effects of fat with protein or energy were not observed. Toms responded more favorably to early protein than energy restriction, regardless of the fat content of the realimentation diet