Microbiological baseline study of swine carcasses at Swedish slaughterhouses.
This 13-month survey was conducted to estimate the prevalence and counts of foodborne pathogenic bacteria and indicator bacteria on swine carcasses in Sweden. A total of 541 swine carcasses were sampled by swabbing prechill at the 10 largest slaughterhouses in Sweden. Pathogenic Yersinia enterocolitica was detected by PCR in 16% of the samples. The probability of finding Y. enterocolitica increased with increasing counts of Escherichia coli. No samples were positive for Salmonella. The prevalences of Campylobacter, Listeria monocytogenes, and verocytotoxin-producing E. coli were low (1, 2, and 1%, respectively). None of the verocytotoxin-positive enrichments, as determined by a reverse passive latex agglutination assay, tested positive for the virulence genes eaeA or hlyA by PCR. Coagulase-positive staphylococci, E. coli, and Enterobacteriaceae were recovered from 30, 57, and 87% of the samples, respectively, usually at low levels (95th percentiles, 0.79, 1.09, and 1.30 log CFU/cm2, respectively). The mean log level of Enterobacteriaceae was 0.35 log CFU/cm2 higher than that of E. coli on carcasses positive for both bacteria. The mean log level of aerobic microorganisms was 3.48 log CFU/cm2, and the 95th percentile was 4.51 log CFU/cm2. These data may be useful for risk assessment purposes and can serve as a basis for risk management actions, such as the use of E. coli as an alternative indicator organism for process hygiene control.
Lindblad
M
M
National Food Administration, P.O. Box 622, SE-751 26 Uppsala, Sweden. mats.lindblad@slv.se
Lindmark
H
H
Lambertz
S Thisted
ST
Lindqvist
R
R
D000003:Abattoirs; D000818:Animals; D001420:Bacteria, Aerobic; D002167:Campylobacter / Q000302:isolation & purification; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004755:Enterobacteriaceae / Q000302:isolation & purification*; D004926:Escherichia coli / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D006801:Humans; D008089:Listeria monocytogenes / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D018570:Risk Assessment; D013548:Sweden / Q000453:epidemiology; D013552:Swine / Q000382:microbiology*; D015008:Yersinia enterocolitica / Q000302:isolation & purification*