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Effects of Phase Feeding on Broilers Performance

This study was conducted to determine the effects of phase feeding on broiler performance. A total of 240 day old male and female Ross 308 chicks were used in a completely randomized design in 4 treatments and 3 replicates for each treatment and 20 birds per replicate. The first treatment was considered in 3 phase schedule. The second treatment included pre-starter, starter, grower 1, grower 2, finisher 1 and finisher 2 with 24, 22, 21, 20, 19 and 18 percent CP respectively. The third treatment was scheduled in starter (0-14) with 22 percent CP, grower (15-28) with 21 percent CP and finisher (29-42) containing 18 percent CP. The fourth treatment included starter (0-21) with 21 percent CP and finisher (22-42) with 19 percent CP. There was no metabolizable energy variation between the diets: 3010 Kcal/Kg for the starter diet, 3175 for the grower and 3225 for the finisher.According to the results, feed consumption, body weight gain and feeding conversion ratio were significantly affected when feed phases were increased (p<0.05), but carcass composition was not influenced (p>0.05).To determine the economical performances, feed consumption cost, metabolizable energy, CP, digestible lysine, threonine and sulfur amino acids consumption per Kg of weight gain were calculated and analyzed. Economical traits were significantly influenced by increasing feed periods (p<0.05). The first and the second treatments led to the best performance but the fourth one caused the worst. Production index which is one of the most important economical traits was also evaluated. Means comparison showed that increasing feed phases had a significant effect on this trait (p<0.01). Second treatment had the best and the fourth one had the worst effect on the production index. According to the results, increasing feed phases leads to a trend of meeting age-related requirements of chickens. Hence, better daily weight gain and other improved performances will be obtained.