The optimal condition of broiler chickens at the moment of slaughter should be known in order to produce the highest quality meat. Several and related pre- and post-slaughter factors are involved in ultimate poultry meat quality. In normal operation, feed is withdrawn from birds 6 to 8 hours before catching, resulting in a feed and water withdrawal total period of 8 to 12 hours prior to slaughter, in order to empty the digestive system and minimise fecal contamination. The most critical points for cross-contamination are scalding, plucking and evisceration, due the great amount of micro-organisms present in skin, feather and feet, and due to intestine breakage during evisceration. However, carcass dehydratation begins immediately after feed withdrawal, and a prolonged period without feed and water can affect pH of the gut, increasing Salmonella and other pathogenic micro-organisms. In addition, excessive feed and water withdrawal times increases bile contamination and are often subjectively associated with increased intestinal fragility during automated evisceration. Thus, processing schedules need to be established to take in account feed withdrawal on gut integrity and fullness, gall bladder status, birds welfare, shrinkage and subsequent effects on carcass contamination and meat quality. As some effects of feed and water withdrawal are still unknown, research is required in the following area: optimal feed and water withdrawal time in relation to welfare of the birds, carcass contamination, and meat quality parameters; influence of delayed withdrawal on pH and colonization of crop, proventriculus, gizzard, small intestine, colon and ceca by enterobacterias like Salmonella; influence of feed and water withdrawal on liver weight and colour. The expected result is an improvement in animal welfare and meat quality, while reducing losses and costs.
carcass quality; contamination; broiler chickens; feed withdrawal