Robert H Madden

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A surveillance study was carried out to determine the prevalence of Campylobacter in a range of retail foods purchased in three Irish cities over a 20-month period between March 2001 and October 2002. In total 2391 food samples were analysed during this period. Campylobacter was isolated from 444 raw chicken (49.9%), 33 turkey (37.5%) and 11 duck samples(More)
A 1-year study was undertaken to determine the prevalence of Arcobacter spp. in raw milk and retail raw meats on sale in Northern Ireland. Retail raw poultry samples (n = 94), pork samples (n = 101), and beef samples (n = 108) were obtained from supermarkets in Northern Ireland, and raw milk samples (n = 101) were kindly provided by the Milk Research(More)
Sampling of lamb (n = 100) and beef (n = 100) carcasses in abattoirs in Northern Ireland produced no evidence of Campylobacter spp. contamination and when retail packs of beef (n = 50) and pork (n = 50) were sampled these were also apparently free of Campylobacter spp. However, 38% of retail packs of chicken pieces (n = 120), yielded Campylobacter spp.(More)
Four hundred samples of processed animal protein were analysed for the presence of Salmonella using two impediometric methods. The direct method using both Easter and Gibson's, and Ogden's media, as defined in legislation applying throughout the UK, was less selective and sensitive, detecting 30% fewer positive samples than the indirect method using(More)
AIM To investigate and compare the inherent resistance of 40 Salmonella serovars to heat, irradiation and high-pressure stress. METHODS AND RESULTS D10 values for each of the three stresses were calculated for four serovars, chosen as representatives from a catalogue of 40. Based on these results, conditions for each stress were defined, which produced,(More)
AIMS Retail packs of fresh chicken in Northern Ireland were sampled to determine the frequency with which they were contaminated with Salmonella and Listeria spp. METHODS Packs of chicken were chosen from supermarkets ensuring a diverse range of EU producer codes were sampled. Salmonellas were isolated using BS EN 12824: 1998 methodology, biotyped and(More)
AIMS When isolating Campylobacter spp. from retail raw chicken using BS EN ISO 10272-1:2006, contaminants frequently cause overgrowth on mCCDA plates. Therefore, these organisms proliferate in the enrichment medium, Bolton broth, indicating a lack of selectivity in this medium. This study sought to characterize the contaminant flora and to devise a modified(More)
A cross-sectional survey of pigs at slaughter in Northern Ireland was undertaken to determine the overall prevalence of Salmonella infection. In total 513 pigs were sampled across four abattoirs, with Salmonella spp. isolated from the caecal contents of 31.4% (95% confidence interval [CI] 27.4%-35.4%) and from 40.0% (95% CI 35.8%-44.3%) of swabs taken from(More)
AIMS To compare typeability, discriminatory ability, and inter-laboratory reproducibility of three flagellin PCR/RFLP (fla typing) methods previously described for Campylobacter. METHODS AND RESULTS The sample set (n = 100) was diverse, including both C. jejuni (n = 85) and C. coli (n = 15). Two of the three flaA typing methods amplified flaA alone,(More)
To assess the current risks to consumers from Campylobacter and Salmonella in raw chicken products sold in the Republic of Ireland, a retail survey was undertaken to define their prevalence. Samples (n = 510) were analyzed using protocols based on ISO 10272-1:2006 and ISO 6579:2002. Processor codes on pack labels showed that 67% of samples were produced in(More)