Submitted to: Poultry Science
Publication Type: Abstract only
Publication Acceptance Date: 5/15/2005
Publication Date: 7/31/2005
Citation: Musgrove, M.T., Jones, D.R. 2005. Recovery of salmonella from nest run egg cart shelves. Poultry Science.84(SUPP 1):77 Interpretive Summary:
Technical Abstract: A study was conducted to determine if Salmonella could be recovered from the shelves of nest run egg carts at commercial shell egg processing facilities. Eggs that are produced by hens not housed in buildings connected to the processing plant are referred to as nest run eggs. These eggs are transported to the plant on carts to be processed. In a previous survey conducted in our laboratory, data indicated high numbers of Enterobacteriaceae could be recovered by swabbing shelves from the nest run egg carts. In the present study, shelves were swabbed by two methods. A 10 cm x 10 cm sterile gauze pad was moistened with 10 mL phosphate buffered saline (PBS) and used to wipe a 12 x 12 cm section of shelf. An adjacent section of shelf of equal size was then swabbed using a sampling sponge that was moistened with 10 mL of PBS. After swabbing, the gauze (G) or sponge (S) was transferred to a Whirl-pak bag, placed on ice, and transported back to the laboratory. Individual samples were pre-enriched in buffered peptone water, selectively enriched in TT and Rappaport-Vassiliadis broths, and selectively plated onto BGS and XLT-4 agar plates. Presumptive colonies from these plates were used to inoculate LIA and TSI agar slants. Typical reactions were confirmed using Salmonella sero-grouping anti-sera. There were 73.3% (11/15) G and 66.7% (10/15) S Salmonella positives from nest run cart shelves at the first plant. At the second plant only 4.0% (1/25) G and 4.0% (1/25) S samples were confirmed as Salmonella. All Salmonella isolates were sero-grouped as B or C. None of the isolates were identified as being from D, the sero-group that includes S. Enteritidis. Each of the methods was equally effective at recovering Salmonella but gauze pads were easier to prepare and less expensive to use. These data also indicate nest run cart shelving as a potential Salmonella reservoir in the commercial processing plant environment.