Listeria monocytogenes in poultry and poultry products: epidemiological investigations in seven Danish abattoirs

Abstract

Listeria monocytogenes was isolated from 11/236 (4 x 7%) caecal samples from parent flocks, providing broilers to the abattoirs investigated. Caecal samples from 2078 broilers representing 90 randomly selected broiler flocks were negative for L. monocytogenes. A total of 3080 samples from seven abattoirs including poultry processing line samples, and final products were also examined for L. monocytogenes. Listeria monocytogenes was isolated in 0 x 3% to 18 x 7% of the samples collected in the different abattoirs. Epidemiological typing of 247 L. monocytogenes isolates, including serotyping, phage typing, pulsed-field gel electrophoresis and ribotyping revealed 62 different clones. Based upon typability and discriminatory power, DNA typing methods used were found equally suitable as epidemiological markers. Serotyping and phage typing were not found useful as epidemiological markers for poultry isolates of L. monocytogenes since only 120/247 (48 x 6%) isolates were typable by phage typing and 230/247 (93 x 1%) L. monocytogenes belonged to serotype 01 while 6/247 (2 x 4%) belonged to 04. The discovery of a few dominating clones in each abattoir might indicate an endemic occurrence of L. monocytogenes. It is concluded that L. monocytogenes in the broiler production is primarily localized to the abattoirs. The incidence of L. monocytogenes may be reduced by improving the hygiene.

Application of a Multiplex Polymerase Chain Reaction Assay for the Simultaneous Confirmation of Listeria monocytogenes and Other Listeria Species in Turkey Sample Surveillance

“…In addition, older birds are more resistant to experimental challenge than are younger birds, the majority of which rapidly clear the infection (40). Studies conducted at a slaughterhouse indicate that contamination of turkey products occurs during processing, especially after evisceration and chilling (15,27). In addition, the Food Safety and Inspection Service microbial baseline conducted in 1995 reported L. monocytogenes in carcass washes of 15% of broilers and 5.9% of turkeys.…”

“…Carriage estimates for live chickens, based on cecal samples from parent breeders (4.7%) and 2,078 broilers (0%) (27) as well as broiler ock surveys (3% of 71 ocks were positive) (28), indicate that L. monocytogenes is infrequently found in live adult birds. In addition, older birds are more resistant to experimental challenge than are younger birds, the majority of which rapidly clear the infection (40).…”

“…In another report, although L. monocytogenes was not cultured from the intestinal tracts and ceca of turkeys at slaughter, it was recovered from processing water, from mechanically deboned meats, and from the hands and gloves of 34% of the meat cutters (15). Additional studies involving DNA pro les of L. monocytogenes indicate that signi cant cross contamination occurs during poultry processing (27).…”

Meta-analysis of the incidence of foodborne pathogens in Portuguese meats and their products

“…2) has been obtained from only two available primary studies (Antunes et al, 2002;Mena et al, 2004), at present the main recommendation can be for enabling actions to address the data gap. Djeniyi, Wegener, Jensen, and Bisgaard (1996) indicated that because L. monocytogenes is not frequently isolated from chickens, it is likely that the live animals may only contribute little to the total contamination of the abattoir, and that the pathogen may be introduced from dirty transport crates. Even though, poultry has not been associated to a great extent with human listeriosis, variable incidence rates of this pathogen have been found in the past in Denmark (23%; Djeniyi et al, 1996), USA (30%; Cox, Bailey, & Berrang, 1997), Ireland (6-30%;Whyte, McGill, Monahan, & Collins, 2004), Northern Ireland (17%; Soultos, Koidis, & Madden, 2003) and Brazil (28%; Loura, Almeida, & Almeida, 2005).…”

“…Djeniyi, Wegener, Jensen, and Bisgaard (1996) indicated that because L. monocytogenes is not frequently isolated from chickens, it is likely that the live animals may only contribute little to the total contamination of the abattoir, and that the pathogen may be introduced from dirty transport crates. Even though, poultry has not been associated to a great extent with human listeriosis, variable incidence rates of this pathogen have been found in the past in Denmark (23%; Djeniyi et al, 1996), USA (30%; Cox, Bailey, & Berrang, 1997), Ireland (6-30%;Whyte, McGill, Monahan, & Collins, 2004), Northern Ireland (17%; Soultos, Koidis, & Madden, 2003) and Brazil (28%; Loura, Almeida, & Almeida, 2005). Thus, these and the Portuguese results highlight that the presence of L. monocytogenes in Portuguese broiler meat would not be uncommon; and hence, maintaining good hygiene practices in production, processing and the consumer's kitchen cannot be overemphasized.…”