Rapid culture method identifies Salmonella species in duck eggs

Thermo Fisher Scientific Inc 's Oxoid Salmonella Precis culture method provides fast and reliable detection of Salmonella species in food, animal feed and environmental samples. In light of the recent outbreak of Salmonella Typhimurium DT8 in Ireland, linked with the consumption of duck eggs, food testing laboratories require methods which can rapidly and accurately identify salmonella species in food. The Oxoid Precis method delivers dependable analytical results in just two days, which is up to three days faster than conventional Salmonella culture methods.

The Food Safety Authority of Ireland (FSAI) reports that the recent food poisoning outbreak of salmonellosis is the largest one recorded in recent years in Ireland. The outbreak is still ongoing and the latest cases have been linked to the consumption of duck eggs from small backyard flocks and private farms. Salmonella is a genus of rod-shaped, Gram-negative Enterobacteriaceae known to cause symptoms that vary from vomiting and diarrhea to life threatening illness.

In response, the Department of Agriculture, Fisheries and Food (DAFF) has published a code of practice for commercial flock owners. The code specifies that flocks must have an effective Salmonella monitoring programme in place and comply with the minimum levels recommended by DAFF. Duck flocks intended for the production of table eggs should be tested for Salmonella at least at the day-old stage, at four weeks of age, at two weeks before moving to the laying phase or laying unit, at 22 to 28 weeks and every 15 weeks during the laying phase. Given that a commercial flock breeds hundreds of ducks at different ages, Salmonella monitoring at such a facility is a continuous process requiring fast turnaround of results in order to detect contamination as early in the process as possible.

The Oxoid Salmonella Precis culture method achieves the fast turnaround times required for Salmonella monitoring. The procedure is carried out in just two days, in three simple steps - enrichment, plating and confirmation.
The single 18-hour enrichment is achieved using Oxoid ONE Broth-Salmonella, a highly nutritious medium that promotes recovery and growth of the target organism while inhibiting competing organisms. The growth promoter in the medium allows the recovery of stressed Salmonella cells, even when present in very low numbers. Plating is undertaken on Oxoid Brilliance Salmonella Agar that incorporates Inhibigen technology, which improves the recovery of Salmonella by reducing background flora. The identification is confirmed using the Oxoid Salmonella Latex Test, a quick and easy method for the confirmation of Salmonella species from culture media.

Simon Kirk, product manager at Thermo Fisher Scientific, comments: "The Oxoid Salmonella Precis culture method effectively addresses the requirement of food testing laboratories for rapid turnaround of results. The method is validated and approved by AFNOR to the ISO 16140 standard and requires no specialized equipment, minimizing handling. Using just a single broth and plate for each sample saves valuable laboratory space and reduces the volume of waste."

Oxoid is a specialty brand that complements the Thermo Scientific offering for the food safety industry, including a wide range of sample collection, sample preparation, instrumentation and data management products focused on the needs of food safety. In addition, a broad portfolio of chemicals, consumables, equipment and supply chain services are available through the Fisher Scientific brand. From research to testing and monitoring, Thermo Fisher provides methods-based consulting and applications support in addition to a comprehensive line of products. Thermo Scientific solutions enable fast and accurate testing of potentially harmful contaminants in food
including chemical residues, fungicides, natural toxins, pathogens, pesticides, trace elements and veterinary drugs

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