The effects of using different feed restriction periods on growth performance and blood parameters in Ross- 308 broiler chicks

Current experiment was conducted to investigate the effects of different feed restriction periods on the performance and blood biochemical parameters of Ross-308 broiler chicks. 192 chicks from 10 to 42 days were used in 4 treatments, 4 replicates and 12 chicks in each replicate in growth (11 to 24 days) and finishing (25 to 42 days) in a completely randomized design. Treatments included: 1) control (without feed restriction), 2) 8 hours feed restriction (from 8 to 28 days of age), 3) 16 hours feed restriction (from 8 to 25 days of age) and 4) feeding skip a day (from 8 to 21 days). Feed restriction had significant effects on broilers' performance and blood biochemical parameters (P<0.05). In the growth period, feed restriction in contrast with the control group, reduced the growth performance of broilers. In this period, daily feed intake, daily growth weight and weight in final period decreased, whereas feed conversion ratio increased. But in the finishing period, feed restriction caused the amount of weight gain to increase and the feed conversion ratio reduces. Feeding skip a day caused the amount of daily feed intake to reduce (P<0.05). In contrast with control group, feed restriction caused the amounts of blood HDL to decline and total protein increased (P<0.05). In conclusion, using 16 hours feed restriction between 8 to 25 days in Ross-308 broilers breeding period, cause the performance index improve.