The importance of cleaning and disinfecting

Planning for the logistics of turnaround is a big undertaking, but carrying out a thorough cleaning and disinfection process is critical to maximising the performance of the incoming flock.

With the free range sector facing a growing number of challenges, producers cannot afford to hinder flock performance by allowing a build-up of micro-organisms in their housing.  As turnaround times get tighter, the opportunity to rest buildings inbetween flocks has been lost, meaning the quality of cleaning and disinfection is more important than ever.

Lancashire based cleaning specialist Steve Birchall told us that even low disease levels can drag profits back and that skimping on the cleaning routine between flocks is a false economy.

“Too many producers regard cleaning as a ‘must do’, that is purely a mundane and uninteresting chore, however nothing could be further from the truth”, Steve said.  “Cleaning should be seen as an integral part of a production system which can have a significant impact on performance, costs, and profits”.

Steve first began cleaning poultry sheds in 1985 with a small van and an electric washer, but he now operates nationwide with three cleaning teams specialising in free range and multi-tier systems.

He said: “Older buildings are often more difficult to clean than modern ones, but if you are going to do the job at all then it is worth doing properly and you have to commit enough time.  This is particularly the case in laying units because the nest boxes and equipment have been in place for 12 months or more”.

The process consists of two distinct but interrelated stages – cleaning and then disinfection.

“Cleaning is essential for removing the environment in which pathogens thrive and to expose them to the subsequent disinfection.  You cannot disinfect dirt and unless it is removed the pathogens will be protected from disinfectant”, Steve explained.

“This cleaning phase is crucial, but it is not simply a case of taking an ardent approach with a high pressure power washer.  Whilst you can blast away some soiling, you will not remove the fats and proteins which make up the dirt on walls and other surfaces.  In addition, the use of high pressure creates an aerosol effect which can actually spread the pathogens and make the problem worse”, he continued.

“Using a chemical detergent ensures that soiling is removed before disinfection, resulting in a reduction in bacterial levels prior to restocking, giving the new birds the best possible start”.

Once the poultry unit is clean, then a Defra approved disinfectant can be used.

Steve said: “I personally believe that it is good to regularly switch what disinfectant you use, do not stick with the same one – sometimes a change is as good as a rest.  All of the products should be biodegradable and safe, should there be a run-off into a watercourse”.

Growing resistance to antibiotics is pressuring the industry to explore alternative ways to reduce pathogen risks to birds and Steve believes that more efficient cleaning processes, combined with strict biosecurity, are an obvious starting point.

He said: “New stock are under stress brought about by a combination of factors, including transport, handling, and vaccination, so the more that can be done to reduce disease threats, the better.  There is real scope to improve the effectiveness of cleaning all types of poultry housing, but the starting point is a change of mindset”.

Whilst some producers choose to carry out cleaning and disinfection themselves, Steve claims that it is worthwhile investing in a professional outfit who are experienced in the process.

He explained: “Many producers simply do not have the time to master the techniques, if there are different enterprises on the farm they have to keep breaking off to do other work.  Individually talking through each case with a professional means that the right course of action can be prescribed and it takes the headache of cleaning away from the farmer so they can get on with their day to day work”.

 

David Hodson of Rosehill Poultry Vets noted that keeping flocks for longer means that cleaning and disinfection at turnaround is even more important.

He said: “One of the main challenges we are now facing in longer lived birds, on both newly established and older sites, is to keep getting the basics right.  A thorough terminal disinfection and cleaning protocol is a must, because if the birds are staying 20 weeks longer, then there will be an equivalent extra viral and bacterial load within the shed that must be eliminated before new birds are housed”.

David drew particular attention to the importance of the cleaning and disinfection process in preventing the build-up of red mite populations.

“On turnaround the temperature of the house will drop as soon as the birds are depopulated, because the mite has evolved to go to ground when the food source is no longer present, we need to take a tactical approach to eliminate them”, he said.

“Several sites have gone to 30 weeks before the red mite challenge has returned again, thus taking the birds through a large part of the most challenging period.  This ensures that the level of stress on the birds is minimal throughout the early weeks”.

He also offered some advice on the different disinfectants for hitting red mite: “The disinfectant, interkokask, used at a rate of 3% is lethal, whilst Chlorocresol, Propionic, and Phosphoric have shown excellent effectiveness used at an approximate rate of 11 litres in 350l of stock solution”.

“When choosing your product, ensure you take into account Defra trial work, as this work is completely independent of the manufacturers.  Looking at this work the two standout products that are available consist of Interkokask and Intercid.  Intercid is comprised of Glutaraldehyde and Formaldehyde which are particularly effective against Salmonella when used at the correct rate”.

Like Steve, David stressed the importance of thoroughly removing all organic matter from the system.

He said: “An insecticide that has been fogged will struggle to penetrate a system that has organic matter present.  When looking for mites there are key spots which offer the mites safety.  The areas under the drinking line clips, in the joints of the metal infrastructure and underneath, and dried on muck or dust will all be replete with mite in a challenged house on turnaround”.

He continued: “The greater the investment in ensuring your new flock is housed in clean, sterile, oocyst and worm free environment, the greater the chance the flock will go on to perform well.  Performance of a laying flock is reliant on many factors, the stress of disease challenge is a key factor and could be the deciding factor”.

 

BFREPA’s ‘Final Cleansing and Disinfection Contingency Planning Workbook’ can be found on the association’s website and provides producers with a way of being prepared for an avian influenza outbreak, and also sets out the cleansing and disinfection process should the worst happen.

This is based upon the same process that most producers will go through at turnaround and involves removing litter and brushing everything down, before applying degreaser, blasting off any visible contamination, rinsing everything top to bottom at a lower pressure, and then applying the disinfectant.  The primary difference between this and clean down during turnaround is that the process has to be carried out at least twice.

Julian Sparrey is Technical Director of Livetec, a company that specialises in the slaughter and clean-up operations on infected sites, he also helped to write the workbook with BFREPA.  He offered an insight into the cleaning and disinfection process after an AI outbreak.

“It is more complex because you have to work with APHA and adhere to their guidelines”, he told us.  “In the case of an outbreak you have to draw up a plan with them, which is based on your usual process at turnaround, and adapt it to their requirements”.

“The procedure seems very straightforward, but it’s formulaic nature can lead to problems.  It does not take into account procedures for things like unpacking slats or taking nest boxes apart, which make the process more complex than APHA’s plans allow for and can throw up issues regarding the order in which things are done”.

He continued: “Any repairs to the housing must also be completed before substantial cleaning.  For example, rotten boards and cracks in the concrete have to be dealt with because contamination can be held in them and APHA will not lift restrictions until they are dealt with”.

Julian also told us about how producers need to treat the range following an outbreak.

“A couple of free range units were hit by AI this year, so APHA have worked out how they want to deal with ranges practically”, he said.

“Producers must leave the range for 56 days and keep the grass short, as they are relying on sunlight getting down onto the soil to kill any remaining virus.  APHA will also want any areas of the range that are muddy or rutted, as well as any area that has been under a mobile house, to be cultivated out, treated with lime, and then rolled back down.  Similarly, any parts of the range that are bowl shaped, or liable to creating areas of standing water, are expected to be filled in and dealt with”.