EFFECTS OF ADDING ACETIC ACID AND FEED WITHDRAWAL PERIOD ON GROWTH PERFORMANCE OF BROILER CHICKENS DURING THE SUMMER SEASON

Abstract

The present study evaluates the effects of feed withdrawal period and addition of acetic acid in drinking water on growth performance, physiological measurements, carcass traits, carcass chemical composition, intestinal microbial and economic efficiency of broiler chicks during the period of 22 to 42 days of age under Egyptian condition. A total number of 270 of Cobb broiler chick one day old were randomly assigned to six groups and fed a basal diet through the experimental period. The groups T1 (control), T2, T3, T4, T5 and T6 were fed ad libitum, fasting 8 hours, addition of 6% acetic acid, fasting 8 hours with addition of 6% acetic acid, addition of 8% acetic acid and fasting 8 hours with addition of 8% acetic acid, respectively. The highest (P<0.05) final weight and weight gain were recorded for T5 group. While group T2showed the lowest (P<0.05) value. The highest (P<0.05) averages of daily feed intake were reported by T1, T5 and T3 groups. While, group T2 had (P<0.05) the lowest daily feed intake. The best feed conversion ratio (P<0.05) was recorded by the groups T2 and T4. Mortality rate was significantly the highest for the control. Blood serum traits are significantly affected by feeding dietary treatments within normal rage. Dressing carcass weight of T5 birds was significantly the highest compared to T2. Abdominal fat weight was significantly the highest for the control. The total bacteria account was (P<0.05) higher in birds treated acetic acid and the coliform bacteria was significantly lower. European production efficiency factor (EPEF) increased significantly for all treatments except the control. These results concluded that addition of acetic acids (6 and 8%) with feed withdrawal (8 hours at 22-42 days of age) in drinking water during summer season have a positive effect on growth performance of broiler.