They are science-based and the result of the many projects undertaken since 2009.

Our key intervention points are:

• On farm biosecurity
• Catching practices
• Thinning practices
• Crates and modules
• Scalding practices
• Washing practices
• Heat treatments
• Cold treatments
• Novel packaging

This list represents those areas where research is suggesting the largest impact in the shortest time. Other intervention points, such as evisceration practices and kitchen hygiene awareness are still be examined.

On farm biosecurity

Biosecurity is the term used to describe the actions taken to prevent campylobacter entering flocks from the natural environment.

Good husbandry requires farmers to enter the houses a number of times every day to assess the health and welfare of birds, so consistent application of disinfectant foot dips, changing boots and clothing, and physical barriers to stop dirt entering from outside are important elements.

Red Tractor standards now have enhanced biosecurity requirement focused on campylobacter. This includes the human interaction with the flocks and also standards of cleanliness for all areas of the farm. Raising awareness of biosecurity, delivering appropriate training, and supporting consistent application are key areas of work for all chicken producing companies.

Research on model farms suggests that near perfect conditions and consistent application of working practices may give us a 10% reduction in the number of flocks infected by campylobacter. This has to be put in the context of farms being exposed to the environment and changing weather conditions, and the variability of working with livestock.

Catching practices

It is essential that catching teams operate to the same standards of biosecurity as farm workers, and Red Tractor standards have been updated to reflect this.

Clothing and equipment entering has to be clean and used in the correct manner. Focus has been on improving awareness and training of catchers, and this work is continuing.

Thinning practices

Thinning is where a proportion of a flock is removed prior (3 to 4 days) to depopulation. This is used to provide birds of different sizes to the retail market.

Work is focusing on limiting the effects of thinning on the remaining birds. For example, reducing the potential for contamination in the catching process, and minimising stress in the rest of the flock that can exacerbate campylobacter colonisation.

Crates and modules

As the equipment used to transport birds from farm to slaughterhouse the crates and modules have a high potential for exposure to campylobacter, and also to move it from site to site.

Traditional techniques that achieve visual cleanliness may leave campylobacter behind in a microbiological film, so work is on-going to enhance cleaning techniques, such as increased use of heat or improved application of disinfectant. Crates impregnated with silver (which has disinfectant properties) are also being trialled.

Practical methodologies for the handling and use of crates and modules are also being explored.

Scalding practices

In the slaughterhouse scalding tanks are vats of hot water through which the bird carcase is passed before de-feathering.

This equipment often sees a build-up of foam on the surface of the water that can increase the risk of cross-contamination between birds. Work is being conducted to look at improving the efficiency of scalding, such as through the use of secondary or multi-stage equipment.

Washing practices

Research has shown that carcase washing equipment operating at a consistently high efficiency can reduce the amount of campylobacter on a carcase by up to 10%. Producers are working on systems designed to maintain high efficiency.

Heat treatments

Campylobacter is sensitive to heat and cold and so interventions in these areas are being researched. Both heat and cold interventions must be balanced with the need to maintain the appearance of the bird that is acceptable to the consumer.

SonoSteam is an intervention that use a combination of ultrasound and steam to reduce the number of micro-organisms on the surface of the bird. More information can be found on their website.

Chill treatments

Rapid surface chilling is the main focus as a chill treatment. This is where nitrogen or air at a very low temperature is sprayed onto the bird to lower the surface temperature and reduce campylobacter. There are a number of variations on this theme, such as the one developed by BOC. The initial trials have demonstrated a 1 to 1.5 log reduction on campylobacter (90% to 95) and the next step for this system is full scale production trials at 10,000+ birds per hour.

Novel packaging

Many retailers are now introducing roast-in-the-bag whole chickens into their stores. By removing the need to handle the bird the intention is to reduce incidences of cross-contamination, and help consumers have good kitchen hygiene practices. The bag with the chicken inside is placed in the oven with the bag being cut open a short time before the end of cooking to allow the bird to brown.

Project outline

Red Tractor Farm Assurance provides information and guidance on best practice standards for farmers and the standards manual are available to all whether or not they are members of the scheme.

In April 2011 Red Tractor Farm Assurance standards were amended to improve bio-security requirements

www.assuredfood.co.uk/resources/000/618/broiler AM9 page 21

Biosecurity standards introduced a designated hygiene area at shed entry which could be as a physical barrier or an area clearly marked off, required a boot change and hand sanitisation at each entry.

Following from the results of research undertaken by SRUC and the industry’s project monitoring effects of biosecurity measures, the Red Tractor Technical Advisory Committee has amended the Standard with the aim of further reducing the risk of introducing campylobacter to a shed via people and equipment. Version 3 of the Standard came into force 1 October 2014 and can be found at the following link.

www.assuredfood.co.uk/resources/000965/985/broiler

The Red Tractor requirements in relation to biosecurity on farm to reduce the risk of introducing disease will be:

• Defined biosecure areas for farm and shed entry and equipment cleaning
• Foot dips at entry to each biosecure area used by all who enter
• Disinfection of vehicle wheels and equipment on entry to farm
• Physical barriers and footwear change at entry to each biosecure area
• Standard Operating Procedure for catching with reference to biosecurity which includes health & safety, hygiene and bird welfare requirements
• Staff on all types of units (breeders, broilers, free range) will require a poultry passport – a qualification for their role in poultry production, which includes a biosecurity module

A number of the standards relating to biosecurity have been upgraded to ‘Key’ standards, which means that a farm will immediately be suspended if they do not comply with the requirement.

Auditing will test that equipment for biosecurity is in full working order to ensure biosecurity requirements are in place and that the systems are being adhered to.

Results

Farms assured to the Red Tractor Chicken standards are audited annually. There are approximately 1600 Red Tractor assured farms in the UK.

Annual results of audit of the new Standard will be discussed in detail by the Red Tractor Technical Team, Chicken Technical Advisory Committee, Poultry Board and Standards Committee, which covers all Red Tractor sectors and has identified campylobacter as a key focus area. Results will also be discussed at industry meetings.

Conclusion

Careful application of biosecurity controls will reduce the risk of the transfer of micro-organisms from the environment to the chicken and from flock to flock.

Applying enhanced biosecurity could lower the possibility of bringing birds into direct contact with campylobacter or of infecting the birds with other diseases which may enable campylobacter to colonise and multiply in the chicken gut.

Project Outline

The initial trial involved 3 farms that had taken part in the larger biosecurity project.

The farms had good biosecurity systems in place and were experienced at taking samples for testing. 25 sheds were tested over 3 crops during the summer months.

Farmers took boot sock samples at thin and at depopulation when appropriate. These were posted to AFBI for testing by PCR. Financial incentives were awarded to the on-farm team for each shed which tested negative for campylobacter.

Results

The 3 farms had a total of 25 sheds, monitored over 3 crops = 75 sheds. Results expressed as % sheds positive:

Control: 2012 results

58% sheds positive at thin
68% sheds positive at depopulation
Combined: 64% positive

Farmer incentive: 2013

40% sheds positive at thin
71% sheds positive at depopulation
Combined: 57% positive

Conclusions

The number of sheds on the trial was too small to be statistically significant, but the results gave enough confidence for industry to extend the trial to a greater number of farms that previously have not tested for campylobacter and the trial will be conducted over the period of a year.

This will mitigate against the possible effects of the summer peak and will drive improved famer behaviour through knowledge of the outcome of their biosecurity controls.

Project outline

To implement agreed biosecurity controls on selected poultry farms and assess their effectiveness at excluding campylobacter from the flocks or reducing the number of bacteria on carcases.

Measurement of the level of contamination was by enumeration of campylobacter in the caeca and on the neck skins.

The project analysed the results of on farm interventions from 16 farms (9 model farms) looking to provide a robust basis on which to base decisions to roll out the effective interventions to all sites. The farms were selected to represent the range of shed types and ages found in UK farms. Standard and enhanced welfare farms were selected.  Each retailer in the project each had at least 1 model farm supplying their product. All major production areas in the UK are represented. The information was generated from both small and large units and contract and company farms.

The results from the model farms were compared to farms populated at the same time and with the same welfare status. Outcomes were measured by comparing the campylobacter enumeration results in the caeca with the results from the random weekly routine test results. The project ran for 2 years from 1^st September 2011 collecting data from 16 crops.

Farm types

Of the 16 farms chosen:

• 10 were enhanced welfare and 6 were standard welfare
• 3 in Northern Ireland, 4 in East Anglia, 2 in the Midlands, 3 in the South West, 3 in Scotland, 1 in Wales
• There was an average of 5 sheds per arm (min. 1, max. 10)

Interventions used

• Standard biosecurity for control farms: Red Tractor assurance scheme for poultry farms
• Additional biosecurity for model farms: Each shed was a biosecure unit with all protective clothing and equipment being shed specific
• Thinning: Additional clothing changes and biosecurity practices during thinning, including module, crate, and transport initiatives
• Depopulation: Clearing sheds within five days of thin to reduce campylobacter load if introduced during thinning
• Shed rest period: Extending the time between flocks while not compromising commercial operations

Each farm was visited and the biosecurity assessed. Regular visits were mad by area managers and the results were provided to the farmers.

Sampling regime

The following tests were carried out to measure the level of campylobacter and assess the success of biosecurity interventions. All testing was done to the ISO standard for enumeration (10272:2) at certified laboratories. Testing of caeca involved 5 samples pooled into 1, and neck skin testing 3 samples pooled into 1.

• Caeca from birds of every model shed at thin (approx. 357 tests per year)
• Caeca from birds of every model shed at depopulation unless campylobacter status is known to be positive (approx. 315 tests per year)
• Neck skins from every model farm (approx. 91 tests per year)

Results

• The data was collected by Industry on 883 crops from 16 farms over 2 years.
• Three quarters of crops have >1000 cfu/g colonisation, while a quarter of flocks have <100 cfu/g colonisation (caeca samples at thin and depopulation)
• There was marked seasonality
• 50% of those found negative at thinning were positive at depopulation (further analysis is being carried out on this)
• There was a very slight significant association between a period of more than 5 days between thinning and depopulation and the crop being positive. However, the data set was quite large which could have the effect of picking up associations which may not have much effect biologically
• The proportion of high risk crops (days between thinning and depopulation >5 days) if reduced to under 5 days will decrease the numbers of positives, but only by 12%. From these results stopping thinning would decrease the Campylobacter colonisation rate-but only by 12%.
• An increase in the number of days that sheds are left empty are strongly linked to a decrease in the caecal campylobacter count at thinning (more than that seen at depopulation)
• There was a trend in lower values of caecal campylobacter count at thin with increasing days of sheds left empty (needs to be confirmed that this is not an outlier (e.g. shed rest days > 20 days) were excluded)

Conclusion

The bio-security standards used on the model farms was unable to totally protect the chicken from colonisation with campylobacter. The project demonstrated that not all sheds on a farm became positive with campylobacter when good bio-security was applied between sheds. In farms using the higher bio-security standards fewer sheds became positive.

Thinning is the term used when some birds are removed from a shed, usually 25-30% and the remained left to grow on. High level bio-security is broken during thinning. Stopping thinning and completely depopulating sheds may result in a reduction of around 12% reduction in campylobacter positive sheds. The results were obtained from a small number of farms and further work is being undertaken to evaluate the effects of stopping thinning.

Further detailed analysis is being  undertaken by an independent organisation.