Effect of quantitative feed restriction on the performance of broiler chickens in Tunisia

The study was conducted to investigate the effect of a quantitative feed restriction phase on the live weight of broilers and assess their compensatory growth performance. Four hundred day-old chicks (Arbor Acres) were reared in four units of 100 chicks. These units were randomized into a control group (T) fed ad libitum and three restricted groups (A, B and C). Chickens of groups A, B and C were limited to 90, 80 and 70%, respectively, of the ad libitum feed intake between 16 and 23 days of age. After the 23rd day of age, all chickens were fed ad libitum until the end of the experiment (42 days of age). Results showed that during the restriction phase the body weight and average daily gain were significantly different (p < 0.01) between the four groups, and higher in chicks fed ad libitum than in those in the restricted groups. Delayed growth was more pronounced in chicks restricted at 70% of ad libitum consumption. After returning to ad libitum feeding, compensatory growth, characterized by rapid growth, was observed just after refeeding in chicks restricted at 70%, at 35 days of age in those assigned the least severe restriction (90%), and in the last week of rearing in the group assigned an intermediate level of restriction (80%). Feed efficiency improved in the restricted groups but the final body weights remained lower than those in the group fed ad libitum. Thus, with an intermediate reduction of the amount of feed consumed (20% for eight days), a final acceptable body weight was obtained