A low residue nutritive supplement as an alternative to feed withdrawal in broilers: efficacy for gastrointestinal tract emptying and maintenance of live weight prior to slaughter.

Experiments were conducted to evaluate the production response to a solid phase, nutritive supplement used as an alternative to feed withdrawal in broiler chickens and its effect on gastrointestinal tract (GIT) residue. Three treatments were applied: a conventional 12-h feed withdrawal (control); provision of a highly digestible, carbohydrate-based feed withdrawal supplement (FWS) with no added protein source (FWS0); and provision of FWS containing 16% CP as a highly digestible protein source (FWS16). Both FWS treatments were designed to be highly and rapidly soluble, were formulated to result in nominally lower GIT residues, and were withdrawn for only 3 h prior to slaughter. Visual assessment of segments of the GIT at slaughter indicated no significant differences among treatments in the degree of emptiness of the crop, gizzard, and colon, whereas intestinal contents of both FWS groups were less (P < 0.05) than those of the control group. With or without prior acclimation to supplements, live weight losses for both FWS groups were consistently and significantly less than for the control group (P < 0.05). In birds acclimated to the supplement, hot eviscerated and chilled carcass weights and deboned breast meat yield were greater for FWS16 than for the control group (P < 0.05). Carcass water uptake during chilling was similar or lower for FWS treatments compared to controls so that the effect of supplement on improving product yield was not due to excessive water uptake. These data indicate that the provision of a highly digestible feed withdrawal supplement enhanced lower GIT emptying, reduced live weight loss, and in some instances improved product yield without the need for a prolonged period of feed withdrawal.