بررسي اثرات زمان محدوديت خوراك و عملكرد جوجه هاي گوشتي

Effect of Time of Feed Restriction on the Performance of Brioler Chickens

In a factorialy designed experiment the effects of quantitative feed restriction in starter (7- 14 days) and finisher (42-49 days) period at three levels of restriction (10, 20 and 30% ad libitum) on 392 (4 replicates of 7 birds in each replicate) Ross broilers were investigated. The criterions for which performances judge were based on 49 days of age and body weight (1.850) at the end of trial time of restriction. The time of feed restriction, whether being at early stage or later growth period did not have any significant effect on total feed intake, feed efficiency, body weight at 49 days of age, breast, leg, abdominal fat and carcass ash percentages. Birds on feed restriction at finishing period had 4.4, 5.5, 20.5 and 10.8% lower feed intake at 49 days of age as compared to those earlier stage but their body weight, growth rate and fat content of carcass was higher than other group On the other hand, feed restriction at the end of growing period, treated birds had higher protein content in their carcass and better-feed efficiency ratio. There were no significant differences between body weight of birds on early restriction and control group at 49 days of age, indicating the compensatory growth being accomplished. There was a reduction of 163 and 37 rials (for every Kg live weight) at 49 days of age and 43 and 26 rials for earlier (as compared to control) and late restricted birds respectively.