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چکیده
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Broiler performance to the end of the rearing period may be negatively influenced by delayed access to feed and water immediately after hatch. This study was conducted with 320 Ross 308 broiler chicks, to evaluate the influence of delayed access to feed and water during the neonatal period (0, 16, 32 and 48 h) on performance and gastrointestinal (GIT) growth. The experiment was conducted as a complete randomized design (four replicate, each with 20 chicks). The results showed that extending post-hatch deprivation of feed and water had a significant negative impact on bird performance. Broilers deprived for 48 h had lower body weights, average daily gains and feed intakes compared to the control and to a lesser extent to the other treatments. Average daily gain, daily feed intake and feed conversion ratio were mostly significantly affected by feed and water deprivation regimens during the first week of the rearing period. At marketing age, the negative impact of severe feed and water deprivation on the birds' performance was substantially decreased, though birds with a 48 h delayed access to feed and water had lower average daily gains and feed intakes compared to the control. Birds mortality rate (%) was not affected by feed and water deprivation during the neonatal period. The results also indicated that the relative weights of the jejunum, ileum and liver of birds getting access to feed and water only at 48 h after arrival were significantly lower when compared to the other groups. The broiler carcass characteristics, abdominal fat percentage at 42 days of age, and gastrointestinal measurements at 21 and 42 days of age were not influenced by the different treatments. In conclusion, the results of this experiment confirmed that immediate access to feed and water after placement will ensure the optimal performance of broiler chicks at market age, and that broiler chicks do not have enough potential to fully compensate for growth retardation caused by long-term depri
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