The information below is an excerpt from the handbook. It is not comprehensive but provides an overview of the key aspects of biosecurity for Parent Stock flocks. For further hints, tips and support in this area, please contact your local Aviagen representative.

Biosecurity impacts on health. Health impacts heavily on welfare and most importantly assurances on food safety.

Producers should have a robust, detailed and clear plan of the tasks that need to be carried out, by whom, when and how. That way not only will there be no room for error, it also means that the work can be checked and assessed to ensure proper practises are being followed. With no ambiguity it is much easier to make sure these critical tasks have been carried out as per instructions to the highest standards.

Cleaning and disinfection

Good health and security practise, of which hygiene is a key part, are necessary for a healthy flock and protecting your workforce. Outlined below are some top tips and areas to consider as part of a thorough cleaning strategy.

Planning: A successful cleanout requires that all operations are effectively carried out on time. A plan detailing dates, times, labour and equipment requirements should be drawn up prior to depleting the farm.

Insect Control: Insects are vectors of disease and must be destroyed before they migrate into woodwork or other materials. As soon as the flock has been removed from the house and while it is still warm, the litter, equipment and all surfaces should be sprayed with a locally recommended insecticide. Alternatively the house may be treated with an approved insecticide within 2 weeks prior to depletion. A second treatment with insecticide should be completed before fumigation.

Remove dust: All dust, debris and cobwebs must be removed from fan shafts, beams, and exposed areas of unrolled curtains in open-sided houses, ledges and stonework. For best results use a brush so that the dust falls onto the litter.

Pre-spray: A knapsack or low-pressure sprayer should be used to spray a detergent solution throughout the inside of the house, from ceiling to floor, to dampen down dust before litter and equipment are removed. In open-sided houses, the curtains should be closed first.

Remove equipment: All equipment and fittings (drinkers, feeders, perches, nest-boxes, dividing pens etc.) should be removed from the building and placed on the external concrete area. It may not be desirable to remove automatic nest boxes and alternative strategies may be required.

Remove litter: All litter and debris must be removed from within the house. Trailers or rubbish skips (dumpsters) should be placed inside the house and filled with soiled litter. The full trailer or dumpster should be covered before removal, to prevent dust and debris blowing around outside. Vehicle wheels must be brushed and spray disinfected on leaving the house.

Litter disposal: Litter must not be stored on the farm or spread on land adjacent to the farm. It must be removed to a distance of at least 3.2 km (2 miles) from the farm, and disposed of in accordance with local government regulations in one of the following ways:

• Spread on arable crop land and ploughed within 1 week.
• Buried in an approved ‘landfill’ site, quarry or hole in the ground.
• Stacked and allowed to heat (i.e. compost) for at least one month before being spread on livestock grazing land.
• Incinerated.
• Burnt as a biofuel for electricity production.

Do check the local regulations in your area before embarking on any of these activities though!

Washing: Before washing starts check that all electricity in the house has been switched off. A pressure washer with foam detergent should be used to remove the remaining dirt and debris from the house and equipment. Many different industrial detergents are available and manufacturer’s instructions should always be followed. The detergent used must be compatible with the disinfectant that will be used to disinfect the house later on. Following washing with detergent the house and equipment should be rinsed with clean fresh water, again using a pressure washer. Hot water should be used for cleaning and excess floor water removed using “squeegees” (a rubber-edged blade set on a handle, typically used for cleaning windows). Wastewater should be disposed of hygienically to avoid any re-contamination of the houses. All equipment, removed from the house must also be soaked, washed and rinsed. Cleaned equipment should then be stored under cover.

Inside the house, particular attention should be paid to the following places:

• Fan boxes.
• Fan shafts.
• Fans.
• Ventilation grills.
• Tops of beams.
• Ledges.
• Water pipes.
• Feed lines.

In order to ensure that inaccessible areas are properly washed, it is recommended that portable scaffolding and portable lights are used.

The outside of the building must also be washed and special attention given to:

• Air inlets.
• Gutters.
• Concrete pathways.

Any items that cannot be washed (e.g. polythene, cardboard) must be destroyed.

When washing is complete, there should be no dirt, dust, debris, or litter present. Proper washing requires time and attention to detail.

Staff facilities should also be thoroughly cleaned at this stage. The egg store should be washed
out and disinfected and humidifiers dismantled, serviced and cleaned prior to disinfection.

Cleaning water and feed systems

The procedure for cleaning the water system is as follows:

• Drain pipes and header tanks.
• Flush lines with clean water.
• Scrub header tanks to remove scale and biofilm deposit and drain to the exterior of the house.
• Refill tank with fresh water and add an approved water sanitizer.
• Run the sanitizer solution through the drinker lines from the header tank ensuring there are no air locks. Make sure the sanitizer is approved for use with the drinker equipment and is used at the correct dilution.
• Make up header tank to normal operating level with additional sanitizer solution at appropriate strength. Replace lid. Allow disinfectant to remain for a minimum of 4 hours.
• Drain and rinse with fresh water.
• Refill with fresh water prior to chick arrival.

Biofilms will form inside water pipes and regular treatment to remove them is needed to prevent decreased water flow and bacterial contamination of drinking water. Pipe material will influence rate of biofilm formation. For example, biofilm tends to form quicker on alkathene pipes and plastic tanks. The use of vitamin and mineral treatments in drinking water can increase biofilm and aggregation of materials to the pipes. Physical cleaning of the inside of pipes to remove biofilms is not always possible; therefore between flocks biofilms can be removed by using high levels (140 ppm) of chlorine or peroxygen compounds. These need to be flushed completely from the drinking system before birds drink. Cleaning may need to include acid scrubbing where the water mineral content (especially calcium or iron) is high. Metal pipes can be cleaned the same way but corrosion can cause leaks. Water treatment before use should be considered for high mineral waters.

The procedure for cleaning the feed system is as follows:

• Empty, wash and disinfect all feeding equipment i.e. feed bins, track, chain, hanging feeders.
• Empty bulk bins and connecting pipes and brush out where possible. Clean out and seal all openings.
• Fumigate wherever possible.

Repairs and maintenance

A clean, empty house provides the ideal opportunity for structural repairs and maintenance to be completed. Once the house is empty, pay attention to the following tasks:

• Repair cracks in the floor with concrete/cement.
• Repair pointing (mortar joints) and cement rendering on wall structures.
• Repair or replace damaged walls, curtains and ceilings.
• Carry out painting or whitewashing where required.
• Ensure that all doors shut tightly.

Disinfection

Disinfection should not take place until the whole building (including the external area) is thoroughly cleaned and all repairs are complete. Disinfectants are ineffective in the presence of dirt and organic matter.

Disinfectants, which are approved by regulatory agencies for use against specific poultry pathogens of both bacterial and viral origin, are most likely to be effective. Manufacturers’ instructions must be followed at all times.

Disinfectant should be applied using either a pressure-washer or a backpack sprayer.
Foam disinfectants allow greater contact time increasing the efficiency of disinfection. Heating houses to high temperatures after sealing can enhance disinfection.

Most disinfectants have no effect against sporulated coccidial oocysts. Where selective coccidial treatments are required, compounds producing ammonia should be used by suitably trained staff. These are applied to all clean internal surfaces and will be effective even after a short contact period of a few hours.

It is vital that external areas are also cleaned thoroughly. Ideally, poultry houses should be surrounded by an area of concrete or gravel, 1-3 m (3-10 ft) in width. Where this does not exist, the area around the house must:

• Be free of vegetation.
• Be free of unused machinery/equipment.
• Have an even, level surface.
• Be well drained and free of any standing water.

Particular attention should be paid to cleaning and disinfection of the following areas:

• Under ventilator and extractor fans.
• Under the feed bins.
• Access routes.
• Door surrounds.

All concrete areas should be washed and disinfected as thoroughly as the inside of the building.

Evaporative cooling and fogging systems can be sanitized at cleanout using a bi-guanide sanitizer. Bi-guanides can also be used during production to ensure that the water used in these systems contains minimal bacteria reducing bacterial spread into the poultry house.

Evaluation of farm cleaning and disinfection efficiency

A key part of good biosecurity is having some form of evaluation in place. It is essential to monitor the efficiency and cost of cleaning out and disinfection. The effectiveness of cleaning is commonly evaluated by checking for Salmonella isolations and total viable bacterial counts (TVC) may also be useful. Monitoring trends in Salmonella /TVC’s will allow continuous improvement in farm hygiene, and comparisons of different cleaning and disinfection methods to be made.

When disinfection has been carried out effectively, the sampling procedure should not isolate any Salmonella species. For a detailed description of where to sample, and recommendations of how many samples to take, please consult your Aviagen veterinarian.

Key Points

• A clear and implemented program of hygiene management should be in place for site biosecurity, and site cleaning and disinfection.
• Site cleaning must cover both the interior and exterior of the house, all equipment and external house areas as well as the feeding and drinking systems.
• Appropriate planning and evaluation of the cleaning and disinfection procedures must be in place.

Summary

So, there you have it. Cleaning, a chore many don’t like but one of the most critical parts of running a successful business and ensuring good flock performance. Quality training, planning and allocation of specific roles to team members will all help ensure that nothing gets missed.