Wa. Warren et Jl. Emmert, Efficacy of phase-feeding in supporting growth performance of broiler chicks during the starter and finisher phases, POULTRY SCI, 79(5), 2000, pp. 764-770
A feeding regimen has been developed that uses regression equations to pred
ict amino acid requirements over time. Phase-feeding (PF) of broilers was t
ested to evaluate its efficacy compared with feeding broilers NRC or Illino
is ideal chick protein (IICP) recommendations, in Experiment 1, NRC or IICP
requirements for lysine, sulfur amino acids, and threonine were fed from 0
to 21 d, whereas PF was tested using a series of three diets (0 to 7, 7 to
14, and 14 to 21 d). No differences (P > 0.05) in weight gain, feed intake
, feed efficiency, digestible amino acid intake, or gain per unit digestibl
e amino acid intake were noted among chicks fed NRC, IICP, or PF diets. In
Experiment 2, NRC or IICP requirements were fed from 40 to 61 d, whereas PF
was tested using a series of three diets (40 to 47, 47 to 54, and 54 to 61
d). No differences (P > 0.05) in weight gain or feed intake were observed,
but the feed efficiency of birds fed the IICP diet was decreased (P < 0.05
). The IICP and PF diets resulted in decreased (P < 0.05) digestible lysine
and threonine intake; gain per unit digestible lysine and threonine intake
was increased (P < 0.05) by PF. No differences (P < 0.05) in breast meat,
wing, or leg yield were noted among treatments. Economic analysis indicated
that PF may facilitate reduced dietary costs without sacrificing growth pe
rformance or carcass yield.