comparison of multi-step phase-feeding programs (eight or thirteen steps) with acommercial three-step feeding program for broiler chickens

Two trials were conducted to study the effect of multi-steps phase-feeding (pf)program on growth performance of broiler chickens from 1 to 24 and 1 to 39d of age. the control group was the nutrient recommendation of aviagen(2019) with a three-step pf program (1-10, 11-24 and 25-39 d of age). in thefirst trial, the control group was compared with an eight-step pf program(pf8), and in the second trial, it was compared with a thirteen-step pf program(pf13). a gradual increase of metabolizable energy and a decrease of crudeprotein and amino acids were applied in pf8 and pf13 over time of life.treatments were replicated in 5 pens of 15 males per each. feed conversionratio, lysine intake efficiency and feed cost efficiency were improved (p ≤0.05) by the pf8 and pf13. in trial 1 (during 1 to 24 and 1 to 39 d of age) andtrial 2 (during 1 to 39 d of age), energy intake efficiency was increased (p ≤0.05) by the multi-step pf program. in trial 1 (during 1 to 24 and 1 to 39 d ofage) and trial 2 (during 1 to 24 d of age), average daily gain was not improved(p > 0.05) by the multi-step pf program compared to the control group;however, the pf13 increased (p ≤ 0.05) average daily gain during 1 to 39 d ofage. in conclusion, the current study shows the eight-step or thirteen-step phasefeeding program improves feed conversion ratio compared to the currentcommercial three-step feeding program. meanwhile, the thirteen-step phasefeeding program increases weight gain from 1 to 39 d of age.