Forty-eight-hour cycle sequential feeding with diets varying in protein and energy contents: adaptation in broilers at different ages.

Sequential feeding is a cyclic feeding program with 2 diets for 1 or several days used to induce lower feed costs or to improve welfare quality. The aim of the present study was to investigate the effects of energy [2,800 (E-) and 3,200 kcal/kg (E+)] and protein [230 (P+) and 150 g/kg (P-)] content on daily feed intake and growth in 900 male broiler chickens, and to compare these results with standard feeding (CP = 190 g/kg and ME = 3,000 kcal/kg). Sequential feeding was carried out during 48-h cycles in 2 periods (period 1 = 10 to 17 d of age, period 2 = 18 to 29 d of age). Four treatments were compared during periods 1 and 2: 1) complete diet (C), 2) alternation of diets varying in CP (SP = P+ followed by P-), 3) in energy (S(E) = E- followed by E+), 4) in protein and energy contents (S(EPA) = P+E- followed by P-E+). A fifth treatment (S(EPB)) used an alternation in protein and energy contents during period 2 only. All chickens received the same feed during the finishing period (30 to 35 d of age). Feed intake was similar with sequential feeding and complete feed, but in proportion to total feed intake, chickens overconsumed high energy feeds (E+ and E+P-) during each period, and P- only for period 2 (P < 0.01). During period 2, overconsumption was greater with S(EPA) than S(EPB) (P < 0.01). Weight gain was similar for all treatments during period 1. At 35 d of age, S(E) chickens were heavier than S(EPA) and S(EPB) (P < 0.01). Feed to gain ratio was similar for all treatments for period 1 and increased for S(P), S(EPA), and S(EPB) compared with C and S(E) for period 2 (P < 0.01). Walking ability, carcass conformation, breast yield, and abdominal fat did not differ between treatments, but ultimate pH of breast meat was improved with S(P). In conclusion, growth and slaughtering performances similar to standard feeding can be reached with 48-h cycle sequential feeding using diets varying in protein and energy contents.