This research was aimed at evaluating the effect of different feed withdrawal (FW) periods (3, 6, 9, 12, 15 and 18 hours) on the live bird weight loss, dressed and chilled carcass yield (before and after of water chilling). The attributes of chilled breast meat quality of broilers raised in the conventional system were also evaluated, such as color, water holding capacity (WHC), pH, shear force and cooking loss. In this experiment, 46-day-old Ross broilers were used. The results of this study indicated that prolonged FW periods have a significant effect (P<0.05) on live broiler weight losses, from 2.27% for 3 hours FW to 7.51% for 18 hours FW. The reduction in dressed carcass yields became statistically significant after 9 hours of FW, ranging from carcass yield of 67.4% after 3hours to 66.2% after 9 hours FW. Chilled carcass yields dropped from 74.8% after 3 hours to 73.2% after 6 hours FW (P<0.05). The highest carcass yields were observed for broilers submitted to FW periods between 3 and 6 hours (dressed carcass yield) and 3 hours (chilled carcass yield). No statistical differences (P>0.05) were observed for L*, a* and b values, WHC, pH, cooking losses and pH of the breast meat submitted to different FW periods. Pearson correlation values showed a negative (P<0.001) correlation between pH and L* value, and between L* value and WHC, which varied with FW periods.
feed withdrawal; broiler; breast; yield; meat quality
