Influence of flooring type during transport and holding on bacteria recovery from broiler carcass rinses before and after defeathering

Four trials were conducted to determine whether conventional solid or eleva ted wire mesh flooring, during transport and holding of broilers prior to s laughter, influenced the number of bacteria recovered from feathered and de feathered carcasses. After 4 h off feed, 7-wk-old broilers were placed at c ommercial density into a modified commercial transport dump-coop on either fiberglass sheeting or 2.54 x 2.54 cm wire mesh flooring that allowed feces to fall through. Broilers were transported for 1 h and then held for 13 h under a covered shed before processing. Broilers were killed by electrocuti on, and the vents were plugged to prevent escape of feces. External carcass rinses were obtained twice (from the same carcass) from eight broilers per flooring treatment per trial, before scalding and defeathering and again a fter defeathering and removal of the head and feet. Greater numbers of tota l aerobes, coliforms, and Escherichia coli were recovered from feathered ca rcasses than from defeathered carcasses. Campylobacter count was also less for defeathered than feathered carcasses from the solid flooring treatment but did not significantly decrease following defeathering of carcasses from the wire flooring. The incidence of Campylobacter-positive carcasses was r educed following defeathering for both flooring treatments, but the percent age of Salmonellae-positive carcasses remained constant. Coliform (log(10) 6.20 vs. 5.63 cfu/mL of rinse) and E. coli (log(10) 5.93 vs. 5.36) counts i n the feathered rinses were significantly higher for the solid flooring com pared with wire flooring, respectively. After defeathering, the number of c oliforms (log(10) 3.12) and E. coli (log(10) 2.91) recovered did not differ between flooring treatments. Aerobic plate count (log(10) 7.06 and 4.02), Campylobacter count (log(10) 2.49 and 1.80), and the incidence of Campyloba cter-positive (44 and 11%) and Salmonellae-positive (52 and 50%) carcasses for feathered and defeathered rinses, respectively, did not differ between flooring treatments. These results indicate that although broilers transpor ted and held on solid flooring had noticeably dirtier breast feathers and h igher coliform and EI coli counts prior to scalding and defeathering, bacte ria recovery from external carcass rinses did not differ between the solid and wire flooring treatments after defeathering.