Sampling by Sponge Wipe or Skin Excision for Recovery of Inoculated Salmonella and Campylobacter from Defeathered Broiler Carcasses

Abstract

Broilers may carry Salmonella and Campylobacter on inner and outer surfaces upon arrival at the slaughter plant, and carcasses can be further contaminated during commercial processing. A sensitive, nondestructive, repeatable sampling method would be useful to test carcasses for levels of bacteria before and after specific processing steps to measure either contamination or efficacy of intervention techniques. Blending of excised skin is accepted as an effective sampling method but requires damage to the carcass; this makes repeated measurements on the same carcass difficult. Herein we compare sponge sampling to skin excision to recover inoculated Salmonella and Campylobacter from broiler carcasses. In each of three replications, broiler carcass breast skin was inoculated with approximately 6.0 log antimicrobial-resistant Salmonella and Campylobacter, allowed to dry for 60 s, and sampled by either sponge, skin excision, or sponge followed by skin excision. Antimicrobial-resistant Salmonella and Campylobacter were enumerated from all samples. Skin excision allowed recovery of 0.1 to 0.2 log more inoculated bacteria than did sponge sampling. When excision was used on the same skin previously sampled by sponging, the combination of both methods did not significantly improve recovery compared with sponging alone. Skin excision is slightly more sensitive than sponge sampling; however, for repeated nondestructive sampling of broiler carcasses during processing, sponge sampling may be preferable to recover Salmonella and Campylobacter within 60 s of a contamination event.

Reduction of Bacterial Load on Broiler Carcasses Using Low-Volume Fluidic Nozzles in Combination with 60 °C Water at 450 Psi Pressure

“…Rivera-Perez et al [27] demonstrated a 0.3 log CFU/carcass increase in Salmonella following mechanical defeathering. Our data indicating an increase of Campylobacter following the picker is consistent with the data from Berrang et al [18].…”

“…Breast swab samples (pre-wash swab) were collected according to the method of Berrang et al, [18] using cellulose sponge swabs (Whirlpak Cellulose Speci-Sponge Bags, Whirlpak, Fort Atkinson, WI, USA) moistened with 10 mL of sterile buffered peptone water (BPW, Becton-Dickinson, Sparks, MD, USA). Briefly, the moistened swab was wiped down the skin of the sternal feather tracts from the top of the keel to the bottom of the rib cage (approximately 30 cm 2 three times.…”