Dispatches from IPPE 2015

Anitox and USDA join forces on research into Salmonella isolation in feed

By Jane Byrne

- Last updated on GMT

Anitox and USDA join forces on research into Salmonella isolation in feed

Related tags Salmonella

A multi-faceted approach must be used for testing for Salmonella in feed, concludes a study carried out by pathogen control specialist, Anitox, in tandem with researchers based at the Agriculture Research Service of the US Department of Agriculture (USDA).

Hydrogen Sulfide (H2S) testing - the ‘gold standard’ for physically and biochemically identifying Salmonella ​in feed until now – is not sufficient on its own to return reliable results, say the authors. 

They claim their data points towards the need for more robust practices for analytics and food safety laboratories.

Salmonella​ tainted feed can result in poor performing birds have can also have negative repercussions further down the chain in terms of public health in that it propagates foodborne illness.

But the pathogen, say the researchers, can be difficult to assess and isolate in poultry feed due to uneven distribution.

False negative results

Anitox research, development and analytics manager, Dr Kellie Hogan, presenting the results in a poster presentation at IPPE 2015, said H2S testing from XLT-4 agar to detect the presence of Salmonella ​in feed can, in fact, deliver false negative results, and can mask the pathogen’s presence.

“Salmonella favors warm, damp conditions with little environmental stress, and in these circumstances H2S testing proves highly effective.  

However, the work we’ve just completed confirms that when Salmonella is ‘stressed’ and environmental conditions are less than favorable the pathogen can remain undetected, only to be confirmed as Salmonella within a matter of hours.  

That’s why we advise a comprehensive approach to testing using multiple methods. While H2S should always be considered, the most accurate results can be obtained with a testing regime that includes PCR or other molecular testing alongside H2S analysis,”​ said Hogan.

The authors recommend that samples should be incubated a further 24 hours beyond the initial 24h and feed analysts should examine plates for yellow colonies with a black pinpoint center as they may become black with longer incubation time.

They suggest employing biochemical analysis, such as the use of API testing strips, to determine the biochemical profile.

The researchers note that PCR or qPCR methods mean analysts can rely on the gene sequence alone, without any interference from environmental impacts to the organism.

Related news

Show more

Related products

Stay ahead of the animal feed production curve

Stay ahead of the animal feed production curve

Content provided by FoodChain ID | 03-May-2024 | White Paper

At every stage of animal feed production, from the receipt of raw materials to the end customer, confidence in feed is critical.

Animal AgTech San Francisco, March 18-19, 2024

Animal AgTech San Francisco, March 18-19, 2024

Content provided by Animal AgTech Innovation Summit | 15-Aug-2023 | White Paper

Animal AgTech is the go-to meeting place for the meat and dairy supply chain to accelerate action for animal health and environmental stewardship.

Related suppliers