Practical ways to manage the salmonella threat

The number of salmonella-positive flocks in the UK has fallen dramatically in the last 15 years since the introduction of the British Lion Code Scheme and, in 2009, the implementation of the National Control Plan.

Nonetheless, both Salmonella enteritidis and Salmonella typhimurium, require continued industry vigilance, particularly in the free-range sector.

According to Jean-Paul Michalski, national production manager for Noble Foods – the second largest pullet rearer in the UK – both biosecurity and routine vaccination are critical.

“Getting it right at the rearing stage is absolutely vital, whether it’s for free-range, organic or barn production,” he says. “As a company we take the importance of vaccination very seriously and we aim to produce a pullet that is fully protected and robust enough to face all the health challenges, particularly on free range.

“Our programme is designed to give the bird long-term protection to ensure birds perform to 72 weeks and beyond. Protection against salmonella is an important part of that.

“Obviously free range has its differences and the birds have greater challenges as a result. With the presence of wild birds on the range, Salmonella typhimurium can be more of a problem than for barn or colony birds.

“It is even more important, therefore, that pullets arrive on the laying farms fully protected. That’s absolutely critical for the producer because being positive for Salmonella enteritidis or typhimurium can have a devastating effect on their business.

“I would encourage free-range producers to talk to their pullet rearer and their vet to develop a plan which will give them confidence that they will be able to control any challenge to their flock and to meet the standards required by the National Control Plan for Salmonella.”

As well as ensuring that the birds have a good foundation with a robust vaccination programme, Mr Michalski emphasises the importance of biosecurity and rodent control, even for free-range flocks.

“I think sometimes biosecurity can be overlooked on free range, but it’s vitally important to maintain the basics, such as visitor protocols, ensuring that vehicles are sprayed and foot-dips in and out of units. Rats and mice are among the biggest carriers of salmonella, so rodent control is something that should really be taken seriously,” he says.

The vaccination programme currently used by Noble Foods involves a Gallivac SE live vaccination in drinking water given at week one and repeated at week three. This primes the bird with salmonella ready for Gallimune SE + ST injected into the breast muscle at transfer.

These provide protection against both Salmonella enteritidis and Salmonella typhimurium, and both are prescription only vaccines, so should only be administered in consultation with a vet.

Mr Michalski says that the quality of vaccine and vaccination administration is important to any programme.

“At Noble we recognise that the cost of vaccine is substantial, but the extra investment in the pullet reaps significant rewards both in extra production and reductions in vet and medication costs. We work closely with our vets and the team at Merial Animal Health, which provides training, auditing and, where necessary, equipment to ensure accurate vaccine administration.

“In particular, Merial was instrumental in the move from leg to breast vaccination, providing a training programme for our vaccinators. This has helped to eliminate any lameness caused by damage to the legs during vaccination, helping to maintain an even flock of pullets.”

Helen Houghton, avian manager and veterinary adviser for Merial in the UK, recalls the relatively high levels of Salmonella enteritidis in the national flock in the late 1980s. “The damage to the industry, following Edwina Currie’s revelations, was enormous. We lost consumer confidence, and many businesses closed as a result.

“The UK industry took steps to implement a vaccination programme for salmonella, coupled with improved biosecurity, rodent control and tracing of eggs to be sold through the Lion Code assurance scheme. Now with the salmonella testing for the National Control Plan in place, consumer confidence in the UK egg industry is at the highest it has ever been.”