Assessment of ATP-Bioluminescence and Dipslide Sampling to Determine the Efficacy of Slaughterhouse Cleaning and Disinfection Compared with Total Aerobic and Enterobacterales Counts.

Inadequate cleaning and disinfection (C&D) in slaughterhouses can cause bacterial contamination of meat, resulting in foodborne disease and reduced meat quality. Different methods for monitoring the efficacy of C&D procedures are available, but few studies have assessed their reliability. This study examined C&D efficacy in slaughterhouses and evaluated the diagnostic performance of methods for measuring surface hygiene. One red meat and one poultry slaughterhouse in Sweden were each visited on six occasions before and six occasions after C&D. Sampling points were sampled with: swabbing and plating for total aerobic bacteria (TAB) and Enterobacterales (EB); dipslides for total viable count; and ATP-bioluminescence tests. To evaluate the diagnostic performance of the dipslide and ATP-bioluminescence methods, the results were compared with (TAB) as a reference. In total, 626 samples were collected. For the majority of samples, TAB was lower after than before C&D and EB were mainly detected before C&D, indicating C&D efficacy. Greater reductions in mean TAB were observed in processing areas (2.2 and 2.8 log CFU/100 cm2 in red meat and poultry slaughterhouse, respectively) than in slaughter areas (1.3 log CFU/100 cm2 in both slaughterhouses). Approximately half of all samples were assessed as non acceptably clean (52% for red meat and 46% for poultry slaughterhouse) according to previously published thresholds. Critical food contact surfaces that were insufficiently cleaned and disinfected were plucking fingers, shackles, and a post-dehairing table. Cleaning and disinfection of drains and floors were inadequate. The ATP-bioluminescence method showed low specificity compared with the reference (TAB) in both the red meat (0.30) and poultry slaughterhouses (0.64). The sensitivity of dipslides was low (0.26) in the red meat slaughterhouse compared with TAB. A combination of ATP-bioluminescence and dipslides could provide more accurate estimates of C&D efficacy.

A Structural Equation Model Demonstrating the Relationship between Food Safety Background, Knowledge, Attitudes and Behaviour among Swedish Students.

Traditionally, food safety knowledge has been seen as a factor in improving food safety behaviour. However, the relationship between knowledge and behavior is complex. The aim of the present study was to investigate self-reported data from 408 university students regarding food safety background, knowledge, attitudes, and behaviour using Structural Equation Model (SEM) to examine the influence of different factors on food safety behaviour. The SEM was applied to four factors derived from the data: Background, Knowledge, Attitude and Behaviour. The novelty of this current investigation is the inclusion of the Background factor (genus; experience of cooking and handling different food items; experience of a food safety education course; the foremost sources of food safety knowledge). The factors were constructed from variables with sufficient factor loadings and set up in a predetermined structure confirmed to be valid in previous studies. The results, demonstrated as regression coefficients between factors, confirm that the Background factor strongly influenced Knowledge (0.842). The Knowledge factor, in turn, strongly affected Attitude (0.605), while it did not directly affect Behaviour (0.301) in the same way as Attitude. Attitude had a stronger influence on Behaviour (0.438) than Knowledge. Thus, the Attitude factor seemed to play a mediating role between Knowledge and Behaviour. This indicates that students´ attitudes towards the importance of food safety may have an impact on their food safety behavior, which should have implications for the development of food safety education. This warrants further investigation and practical development.

Reducing Campylobacter jejuni,Enterobacteriaceae, Escherichia coli, and Total Aerobic Bacteria on Broiler Carcasses Using Combined Ultrasound and Steam.

ABSTRACT: Campylobacteriosis is the most frequently reported foodborne illness in Europe and many other parts of the world. Campylobacter can colonize the intestines of broilers, mostly in large amounts. Broilers are usually slaughtered in a high-speed automated system that could cause rupture of the intestines during evisceration, resulting in contamination of carcasses with intestinal bacteria like Campylobacter. This study evaluated the combined effects of ultrasound and steam (SonoSteam) on naturally contaminated chicken carcasses at a large-scale abattoir in Sweden. Ultrasound at 30 to 40 kHz and steam at 84 to 85°C or 87 to 88°C were used at slaughter, with a line speed of 18,000 birds per hour. The amounts of Campylobacter spp., Enterobacteriaceae, Escherichia coli, and total aerobic bacteria on neck skins from 103 chicken carcasses, sampled before and after treatment by ultrasound-steam, were analyzed. Campylobacter spp. were quantified in 58 (56%) of the neck skins, from birds belonging to four of the seven flocks represented. All 58 isolates were identified as Campylobacter jejuni. After the ultrasound-steam treatment, the mean reductions in C. jejuni, Enterobacteriaceae, E. coli and total aerobic bacteria were 0.5 ± 0.8, 0.6 ± 0.6, 0.5 ± 0.6, and 0.4 ± 0.7 log CFU/g, respectively. No significant differences in reduction between the two different treatment temperatures were observed for any of the bacteria. Although the bacterial reductions were significant, large amounts of bacteria remained on the carcasses after treatment. Further studies are needed to identify optimal measures at slaughter to reduce food spoilage bacteria and pathogenic bacteria, which should be considered in a One Health perspective.

Large lungworms (Nematoda: Dictyocaulidae) recovered from the European bison may represent a new nematode subspecies.

Although the Dictyocaulus lungworm, the agent of dictyocaulosis, is one of parasitological threats to European bison, its systematic position remains unclear. The aim of the present study was to evaluate the morphological features of the lungworm and the pathological lesions it induces, and to analyse mitochondrial (mt) genetic markers for systematic and molecular epidemiological studies. The morphological findings indicate that Dictyocaulus lungworms of European bison can be distinguished from those of cattle on the basis of differences in buccal capsule wall length, total body length, and spicules length in males, all of which were significantly longer in those of European bison. Nucleotide diversity calculated from pairwise sequence alignments of partial cytochrome c oxidase subunit 1 (cox1), cytochrome B (cytB) and NADH dehydrogenase subunit 5 (nad5) of specimens from cattle and European bison varied from 1.7% for nad5, 2.1% for cytB, to 3.7% for cox1 gene. Thus, among the lungworms of European bison and cattle, nad5 and cytB were the most conserved proteins, whereas cox1 was the most diverse. The mt cytB marker gene may be a suitable candidate for distinguishing between the two genotypes, as nad5 demonstrated the greatest within-genus sequence variation. The lung tissue of infected European bison manifests signs of verminous pneumonia characterized by interstitial pneumonia, bronchitis and bronchiolitis. Therefore, it appears that European bison and cattle are infected with slightly diverged, morphologically-different, genotypes of D. viviparus, indicating they belong to two separate worm populations. We propose, therefore, that the lungworm of European bison should be classified as D. viviparus subsp. bisontis.