Evaluation of associations between feed withdrawal and other management factors with Salmonella contamination of broiler chickens at slaughter in Alberta.

Salmonellosis is one of the most common bacterial foodborne diseases of public health concern in industrialized countries. Poultry products are considered an important source of Salmonella-related foodborne disease in humans. This study was undertaken to evaluate the relationship between various management factors including feed withdrawal and transportation time with Salmonella contamination in crops, ceca, and carcasses of broiler chickens at slaughter in Alberta. Using a two-stage sampling procedure, 30 matched crop and cecal samples before evisceration and an additional 30 neck skin samples after final wash of broiler chickens were collected at slaughter. A questionnaire was administered at the time of sampling to collect information on flock management risk factors. Cecal contents were individually screened with Salmonella-specific real-time PCR to detect positive flocks, and all cecal, crop, and neck skin samples from positive flocks were processed further for Salmonella isolation and characterization. The flock prevalence of Salmonella was 57.1% and within-flock prevalence of Salmonella for positive flocks was 17.2, 8.1, and 53.9% for ceca, crops, and neck skins, respectively. Salmonella Hadar was the most common serovar identified from crops, ceca, and neck skins of broiler chickens tested. Longer transport (P = 0.04 for neck skins) and waiting time in-plant (P = 0.04 for crops, P = 0.03 for ceca) were identified as important risk factors for Salmonella contamination of broiler chickens at slaughter. Salmonella contamination of broiler chickens could potentially be minimized by reducing waiting time in-plant for flocks with longer transport time.