Evaluation of the relative sensitivity of carcase swabbing against belly strip excision for TVC, E. coli and Salmonella isolation

The standard US method of swabbmg p1g carcases (3x 100cm2) for determination of E. coli and Salmonella contamination was compared with a belly strip excision method (approx. 120cm2). Swabbing for Salmonella and E. coli detection was found to have a relative sensitivity equal to 1/ 7 and 1/ 2 respecl1vely, of the belly strip technique. Furthermore, swab sampling isolated 2 Salmonella serovars compared with 9 serovars by the belly strip technique. For studies on the effectiveness of carcass decontamination interventions or undertaking abattoir flow-through studies it is recommended that belly strip excision sampling be employed. This study also compared the use of a semisolid culture medium (MSRV) for Salmonella isolation developed for faecal samples with standard media. MSRV gave a result 24 hours faster but was not as sensitive as the standard medium (RV). Therefore, MSRV medium is not recommended for the isolation of Salmonella from carcases for regulatory purposes

Longitudinal study of an Australian pig farm infected with monophasic Salmonella Typhimurium-like PT193 (1,4,[5],12:i:- PT193) using MLVA

An Australian weaner-to-finish pig herd with a history of entrenched Salmonella infection (\u3e10 months in duration) was sampled on 5 occasions over a 15 month period commencing in 2011. On each occasion, either 12 or 18 individual pen faecal samples were collected from pigs between 6 weeks and 22 weeks of age (n=71). From the Salmonella positive samples (n=42), a total of 346 isolates were further processed (up to 10 colony picks per sample). All of the 123 isolates typed were identified as monophasic S. Typhimuriumlike PT193 (mSTm193). Results of antibiotic sensitivity testing found 336 of 346 isolates were resistant to ampicillin, streptomycin, sulphathiozole and tetracycline (ASSuT). In addition, all 346 isolates were examined by MLVA and 13 different closely-related MLVA profiles were identified. Only 2 MLVA profiles persisted throughout the 15 month study. This study is the first report of monophasic S. Typhimurium-like PT193, its persistence and associated clinical disease in an Australian pig herd

National baseline surveys to characterise processing hygiene and microbial hazards of Australian culled sow meat, retail pork sausages and retail pork mince

Pork products were sampled at retail to determine the impact of further processing on hazard levels to which consumers may be exposed, compared to carcases. Surveys of 116 fresh pork sausages and 148 fresh pork mince samples were purchased from supermarkets (n=87, n=105) and butcher shops (n=29, n=43), respectively. For sausages, concentrations of TVC averaged 4.6 log10 cfu/g

A new approach to estimating shelf-life

The current approach to the estimation of shelf-life and the determination of the label shelf-life as detailed in the International Conference on Harmonisation guidelines to industry is presented. The shortcomings of the status quo are explained and a possible solution is offered, which gives rise to a new definition of shelf-life. Several methods for calculating a label shelf-life are presented and investigated using a simulation study. Recommendations to adopt the new definition and to increase sample sizes are made. Copyright © 2004 John Wiley & Sons Ltd