Effect of feed restriction severity and meal feeding on live body weight and protein and energy efficiency ratio in broilers

The present study was conducted to investigate the effect of feed restriction severity and meal feeding regimes on live body weight and protein and energy efficiency ratio of Ross broiler chicks. 300, Ross 308 male broiler chicks were reared on the floor pens for 42 days. Birds fed ad libitum for the first week post hatch. Feed restriction schedule was applied from 7 to 14 or 7 to 21 days of age. Chickens in treatment 1 fed ad libitum (AL) throughout the experiment. Birds in treatment 2 and 3 were subjected to quantitative feed restriction based on maintenance (QFRM) or 50% of growth (QFRG) energy requirements. Birds in treatment 4 and 5 were subjected to quantitative feed restriction based on a meal feed schedule from 7 to 14 (MF14) or 7 to 21 (MF21) days of age. Five replicate groups of 12 broilers were allocated to each treatment. Results indicated birds were affected by feed restriction regimes had lower live body weight rather than control group (P<0.05). However, live body weight of MF groups was similar to control group due to compensatory growth but quantitative feed restriction reduced live body weight compared to AL or MF regimes due to incomplete compensatory growth (P<0.05) at the end of experiment. Control group have a numerically superior energy and protein intake (12483.4 kcal and 801.1 g, respectively). Energy efficiency ratio and protein efficiency ratio were superior for birds in MF1 compared to other treatments (17.1 and 2.67, respectively).