Despite data from the European Food Safety Authority (EFSA) in 2011 showing that Salmonella control programmes in laying birds have been highly successful, Alan Doyle, Business Development Manager for Anitox says the industry cannot afford to be complacent.

A recent study in Belgium highlighted the need for caution. The study found that, compared with traditional battery cages and furnished cages, aviary and floor housing systems pose a greater risk. Bird-to-bird transmission of Salmonella enteritidis was slightly higher, while a higher number of eggs were contaminated internally by Salmonella.

With this in mind, Mr Doyle says that Salmonella surveillance programmes must be optimised. "Existing control plans must be maintained and care must be taken to minimise within-flock transmission of Salmonella."

Microbial contamination of feed is a major hazard and so minising contamination of feed is near the top of the list when it comes to implementing an effective bio-security programme.

Heat treatment is one way to minimise the risk, however pathogens may not always be killed. As well as not being 100 per cent effective, heat treating feed increases costs, has a high carbon footprint and can damage nutrients. Re-contamination can occur in the mill, during transport or on the farm.

A formaldehyde-based feed treatment was found by EFSA to provide a viable alternative to heat-treatment, both initially and, crucially, in preventing recontamination of feed. DEFRA-funded research which investigated the treatment of animal feeds with various organic acids and formaldehyde-based products also identified large variations in efficacy and effects in masking the presence of Salmonella during culture.

The treatment which gave by far the best ‘kill’ of Salmonella in feed was a liquid antimicrobial bacteriacide containing 33 per cent formaldehyde, propionic acid and natural terpenes.

Mr Doye says that greater consumer awareness of food safety issues means that livestock producers and feed companies must improve safety throughout the supply chain.