Poultry House Biosecurity: Cleaning and Disinfection Between Flocks

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

Physical removal of organic matter is paramount: Disinfectants are ineffective against pathogens shielded by caked litter, dried manure, or dust; therefore, thorough dry cleaning (sweeping, brushing, blowing down) to remove all visible debris precedes any wet cleaning or disinfection.
Biofilm disruption is critical for disinfection efficacy: A detergent wash is essential to break down the protective biofilm that harbors bacteria and viruses, allowing disinfectants to reach and inactivate pathogens; this step requires adequate soak time and thorough rinsing.
Drying is a non-negotiable step to prevent disinfectant dilution and pathogen survival: Surfaces must be completely dry after washing and rinsing before disinfectant application, as residual moisture dilutes disinfectant concentration and creates a favorable environment for surviving pathogens.
Disinfectant selection and application must be precise: Choose disinfectants labeled for poultry diseases, rotate products to prevent resistance, and apply at the correct concentration and coverage rate with adequate contact time, as specified on the product label.
Environmental sampling verifies disinfection efficacy: Visual inspection alone is insufficient; post-disinfection surface swabbing for indicator organisms like Salmonella or coliforms is the most reliable method to confirm pathogen load reduction and ensure the house is safe for the next flock.
Comprehensive documentation is vital for biosecurity assurance: Maintaining detailed records of cleaning and disinfection procedures, including dates, products used, dilution rates, contact times, and environmental sampling results, provides proof of diligence and aids in identifying recurring biosecurity weaknesses.

Every poultry grower faces the same question after the last bird leaves the house: what is the most reliable way to prepare that space for the next flock? The answer is a systematic approach to cleaning and disinfection, commonly called turnaround cleaning. This article walks through the full process of poultry house turnaround cleaning, from dry removal of litter to the final verification that the house is ready for new birds. It is written for broiler, layer, and turkey producers, as well as farm managers and crew leaders who supervise the work. The focus is on practical steps you can implement with your own crew and equipment, along with the reasoning behind each step so you can adapt the process to your specific houses and conditions.

At a Glance

Start turnaround cleaning only after the house is completely empty and you have confirmed the final removal of all birds with your grower or service technician.
Remove all litter and organic matter first. Disinfectants cannot penetrate caked litter or dried manure, so the physical clean is the most important step.
Dry clean before you wash. Sweep, brush, and blow down all surfaces to remove dust and loose debris before any water enters the house.
Use a detergent and allow it to soak. A good degreaser breaks down the biofilm that protects bacteria and viruses from disinfectants.
Rinse thoroughly from top to bottom, then allow the house to dry completely before applying disinfectant. Disinfectants are diluted by leftover rinse water.
Choose a disinfectant labeled for the specific diseases you are targeting and rotate between approved products to prevent resistance.
Apply disinfectant at the correct concentration and coverage rate. More is not better, but too little will not work.
Allow the house to dry fully after disinfection, then apply a litter treatment or fresh bedding as your program requires.
Keep the house closed and locked during downtime. Control foot traffic, rodents, and wild birds during this period.
Document every step. Records of your cleaning and disinfection prove your program works and help you spot problems early.

Why Turnaround Cleaning Matters

Disease organisms do not disappear when the birds leave. Many pathogens that affect poultry can survive for weeks or months in the house environment. Coccidia oocysts, for example, can survive for a year or more in moist litter. Infectious bronchitis virus can persist on surfaces for several weeks. Salmonella and Clostridium bacteria form protective layers that resist drying. Even a small patch of contaminated litter left in a corner can seed a new flock with disease.

The goal of turnaround cleaning is to break this cycle. You are not just making the house look clean. You are reducing the pathogen load to a level where the birds' immune systems can handle any residual challenge. This is especially important in all-in all-out poultry systems, where the entire house or farm is depopulated, cleaned, and restocked at the same time. All-in all-out management only works when the cleaning between flocks is thorough. If you leave pathogens behind, the new flock starts at a disadvantage.

There is also an economic argument for thorough cleaning. Respiratory disease, enteric disease, and poor feed conversion all cost money. A clean house supports better bird performance. A 2020 review of broiler house cleaning studies found that farms with a consistent cleaning and disinfection protocol had lower mortality and better feed conversion than farms with inconsistent protocols. The exact numbers vary by operation, but the direction is consistent. Cleaning pays for itself in performance.

Finally, turnaround cleaning is a key part of regional disease control. When avian influenza or other reportable diseases are present in your area, your cleaning protocol is your first defense. Regulators and integrators will ask for records of your cleaning and disinfection. A documented program shows that you take biosecurity seriously.

Understanding the Pathogen Challenge

To clean effectively, you need to know what you are fighting. Poultry houses harbor a mix of viruses, bacteria, fungi, and parasites. Each group has different survival characteristics and different sensitivities to disinfectants.

Viruses such as infectious bronchitis, Newcastle disease, and avian influenza are enveloped or non-enveloped. Enveloped viruses have a lipid membrane that is easily disrupted by most disinfectants. Non-enveloped viruses like reovirus are harder to kill. Avian influenza virus is relatively fragile outside the bird, but it can survive for days in organic matter and for weeks in water. The practical implication is that you must remove organic matter before disinfection and choose a disinfectant with proven activity against the viruses of concern.

Bacteria including Salmonella, E. coli, and Clostridium perfringens are common in poultry houses. Salmonella can survive for months in dried feces and dust. Clostridium forms spores that are highly resistant to heat and many disinfectants. Spores require special attention, often meaning a longer contact time or a specific sporicidal product.

Parasites, particularly coccidia, produce oocysts that are extremely resistant. Oocysts have a tough outer shell that protects them from most disinfectants. The only practical way to control coccidia in the house is physical removal of litter and thorough washing to remove all organic material. Some producers use ammonia-based litter treatments to reduce oocyst survival, but these are not a substitute for cleaning.

Fungi such as Aspergillus can grow in damp litter and on surfaces. Mold spores are resistant to drying and many disinfectants. Good ventilation and drying after cleaning are key to mold control.

The common theme is that organic matter protects pathogens. A pathogen sitting in a drop of manure or under a layer of dust is shielded from disinfectant. This is why the physical clean is the most important step. No disinfectant can do its job if the surface is not clean.

Preparing for Turnaround Cleaning

Before you start the cleaning process, take time to plan. A rushed turnaround cleaning will miss spots and leave pathogens behind. Good preparation includes scheduling, equipment checks, and communication.

Scheduling the Work

Coordinate with your grower, service technician, or flock supervisor to confirm the removal date for the last birds. Plan your cleaning to start immediately after the house is empty. The longer the house sits with old litter and manure, the more time pathogens have to multiply and spread. Aim to start dry cleaning within 24 hours of depopulation.

Work backwards from your target placement date to set a realistic schedule. A typical broiler house turnaround takes 10 to 14 days from depopulation to placement. This includes 2 to 3 days for dry cleaning, 2 days for washing, 1 day for drying, 1 day for disinfection, and a minimum of 5 to 7 days of downtime after disinfection. Layer houses may need more time depending on the equipment and the disease history.

Equipment Check

Inspect all cleaning equipment before you start. You will need:

Personal protective equipment including respirators, goggles, gloves, and rubber boots
Dry cleaning tools such as brooms, shovels, scrapers, and a skid steer or tractor with a bucket
A high-pressure washer or foam applicator
Detergent and disinfectant products
A sprayer for applying disinfectant
A leaf blower or air compressor for blowing down dust
Cleaning supplies for the anteroom and equipment

Make sure your pressure washer is in good working order. Check hoses for leaks, test the nozzle, and confirm you have the correct detergent and disinfectant tips. A pressure washer that fails halfway through the wash step will leave you with a half-cleaned house and a schedule problem.

Crew Briefing

Brief your crew on the steps, the safety requirements, and the expected timeline. Emphasize that cleaning must be thorough and methodical. Assign specific areas to specific people so nothing is missed. Review the order of work: dry clean, wash, rinse, dry, disinfect, dry again. Make sure everyone knows that dry cleaning comes before any water enters the house.

Step 1: Remove All Birds and Equipment

The first step is to ensure the house is completely empty. Confirm that all birds have been removed, including any stragglers. Check every pen, corner, and piece of equipment. A single bird left behind will contaminate the entire cleaning process.

Remove all movable equipment from the house. This includes feeders, drinkers, brooders, and any other portable items. Take these to a wash area outside the house where you can clean and disinfect them separately. Equipment that stays in the house, such as permanently mounted feeders or ventilation fans, must be cleaned in place or protected from the cleaning process.

Inspect the house for any structural issues that need repair. Look for holes in the walls, gaps around doors, and damaged flooring. Fix these before you clean so that the house is easier to clean and less likely to admit pests or wild birds during downtime.

Step 2: Dry Clean the House

Dry cleaning is the removal of all litter, manure, dust, and debris without using water. This is the most important step in the entire turnaround process. If you do a poor job here, nothing else will work.

Removing Litter

Start by removing the bulk of the litter. Use a skid steer, tractor, or front-end loader to scrape the litter into piles, then load it into a spreader or trailer. Work from the far end of the house toward the entrance so you do not drive over clean areas with contaminated equipment.

Remove all litter down to the floor or the base material. Do not leave a thin layer thinking it will be fine. Pathogens live in the top layer of the floor and in the dust that has settled into the base. If you use a litter management system that retains a base layer, remove as much as you can and then treat the remaining base with a litter amendment.

Dispose of the litter properly. For most operations, this means spreading it on cropland or composting it. Check your local regulations for disposal requirements. Do not pile litter near the poultry house where it can attract flies and rodents or be blown back into the house.

Sweeping and Blowing Down

After the bulk litter is removed, sweep the floor and walls to remove remaining dust and debris. Use a stiff broom or a floor scraper for caked areas. Then use a leaf blower or air compressor to blow down all surfaces from top to bottom. Start at the ceiling and work down the walls, blowing dust toward the floor. Pay special attention to ledges, rafters, ventilation inlets, and the tops of equipment. This dust is rich in pathogens and must be removed before washing.

Sweep or vacuum the dust from the floor after blowing down. Do not blow dust out the doors where it can contaminate the outside area. Collect it and dispose of it with the litter.

Cleaning the Anteroom and Entryways

The anteroom, changing room, and entryways are part of the house biosecurity zone. Clean these areas during the dry cleaning step. Remove all loose items, sweep and blow down the walls and ceiling, and scrub the floor. These areas will be cleaned and disinfected again later, but a dry clean now prevents cross contamination when you move equipment in and out.

Step 3: Wash the House

Washing is the first wet step. The purpose is to remove the biofilm, grease, and remaining organic matter that dry cleaning could not remove. Washing without detergent is not enough. Detergents break down the organic film that protects pathogens.

Choosing a Detergent

Use a commercial poultry house detergent that is labeled for removing organic matter and grease. These products are usually alkaline or neutral pH and contain surfactants that lift soil from surfaces. Some detergents also have disinfectant properties, but their primary job is cleaning.

Do not use household dish soap or laundry detergent. These products are not formulated for the heavy organic load in a poultry house and may not rinse off properly.

Applying the Detergent

Apply the detergent using a foam applicator or a low-pressure sprayer. Foam is preferred because it clings to vertical surfaces and stays in contact longer. Work in sections. Apply the detergent to one section, let it soak for the time recommended on the label, then rinse that section before moving on.

The soak time is critical. Detergents need time to break down the organic matter. A typical soak time is 10 to 20 minutes, but follow the label. Do not let the detergent dry on the surface, as this can leave a residue that interferes with disinfection.

Washing Techniques

Use a high-pressure washer with hot water if available. Hot water is more effective at removing grease and organic matter. Work from the top down, washing the ceiling, then the walls, then the floor. Use a fan pattern to cover large areas, then switch to a pencil jet for cracks and corners.

Pay special attention to areas that are easy to miss:

The junction between the wall and the floor
Around door frames and thresholds
Under and behind feeders and drinkers
Ventilation inlets and fan housings
Light fixtures and electrical boxes
Cracks in the floor or walls

If you have slatted floors, lift the slats and wash underneath. This area collects manure and is often overlooked.

Rinsing

After washing, rinse all surfaces thoroughly with clean water. Use a high-pressure rinse from top to bottom. The rinse removes the detergent and the suspended soil. If you leave detergent residue, it can neutralize the disinfectant.

Check your rinse water quality. If your water has high mineral content, it can leave a film on surfaces. In some cases, a final rinse with an acid-based product is recommended to remove mineral deposits. Ask your disinfectant supplier for advice based on your water test results.

Step 4: Dry the House

Drying is a step that many producers rush or skip, and it is a common cause of disinfection failure. Disinfectants are diluted by water. If the surfaces are still wet when you apply disinfectant, the disinfectant will be weaker than the label concentration. In addition, many pathogens, including Salmonella and E. coli, survive better in moist environments. A wet house after cleaning can allow pathogens to multiply before disinfection.

Allow the house to dry completely after rinsing. This may take 24 to 48 hours depending on the weather, the ventilation system, and the construction of the house. Run the ventilation fans to move air through the house and lower the humidity. If you have the ability to heat the house, use it to speed up drying. Aim for surfaces that are dry to the touch with no visible moisture.

Check the floor specifically. Concrete floors can hold moisture for a long time. If you have a dirt floor, it will be even harder to dry. In these cases, you may need to adjust your disinfection plan to account for the moisture.

Step 5: Disinfect the House

Disinfection is the step where you apply a chemical product to kill the remaining pathogens. This step only works if the previous steps have been done correctly. A disinfectant applied to a dirty surface is wasted.

Choosing a Disinfectant

Select a disinfectant that is labeled for poultry house use and that has proven activity against the pathogens you are targeting. Common classes of disinfectants include:

Quaternary ammonium compounds are good general-purpose disinfectants. They are effective against many bacteria and enveloped viruses but less effective against non-enveloped viruses and spores.
Phenolic compounds are effective against a broad range of bacteria and viruses, including some non-enveloped viruses. They are often used in footbaths and equipment dips.
Peroxygen compounds such as hydrogen peroxide and peracetic acid are strong oxidizers. They are effective against a broad range of pathogens, including some spores, and they break down into harmless byproducts.
Aldehydes such as formaldehyde and glutaraldehyde are highly effective but are hazardous to handle and may be restricted in some areas.
Chlorine-based disinfectants are effective and inexpensive but are inactivated by organic matter and are corrosive.

No single disinfectant is perfect for every situation. Rotate between two or three approved products to prevent the development of resistance and to broaden the spectrum of activity. Do not mix disinfectants unless the label specifically allows it. Mixing can create toxic fumes or reduce effectiveness.

Applying the Disinfectant

Apply the disinfectant using a low-pressure sprayer or a foam applicator. The goal is to cover every surface with a uniform layer of disinfectant at the correct concentration. Follow the label instructions for dilution rate and coverage.

Most disinfectants need a contact time of 10 to 30 minutes to be effective. The label will state the required contact time. Do not rinse the disinfectant off after application. Allow it to dry naturally.

Work from the top down, just like washing. Cover the ceiling, walls, and floor. Pay extra attention to the areas where pathogens are most likely to hide: cracks, corners, and the junction between walls and floor.

If you are using a fogger or mister to disinfect the air and hard-to-reach areas, use it in addition to, not instead of, the surface spray. Fogging can help reach the ceiling and ventilation ducts, but it does not provide the same coverage as a direct spray.

Equipment Disinfection

All equipment that was removed from the house must be cleaned and disinfected too. Wash each piece with detergent, rinse, dry, and apply disinfectant. This includes feeders, drinkers, brooders, egg belts, and any other equipment. Do not bring equipment back into the house until it has been fully treated.

If you have an equipment wash station outside the house, use it. This keeps contaminated equipment away from the clean house. If you must wash equipment inside the house, do it before you disinfect the house so that the disinfectant can treat the area where the equipment was washed.

Step 6: Apply Litter Treatment or Fresh Bedding

After the disinfectant has dried, you can apply fresh bedding or a litter treatment. The choice depends on your management system.

If you use a total cleanout system, apply fresh bedding material to the floor. Use the same type and depth of bedding that your grower or integrator specifies. Spread it evenly and allow it to settle before placing birds.

If you use a partial cleanout system where you retain a base layer of litter, apply a litter treatment product after disinfection. Litter treatments such as sodium bisulfate or aluminum sulfate lower the pH of the litter and reduce ammonia and pathogen levels. Follow the label rates for your litter type and house conditions.

Do not place birds on wet or damp bedding. The bedding must be dry before placement. This is another reason to allow adequate drying time after disinfection.

Step 7: Secure the House During Downtime

The cleaning and disinfection are complete, but the biosecurity work is not done. The house must stay clean and secure during the downtime period before the next flock arrives. The minimum downtime recommended by most poultry companies is 7 to 14 days. Longer downtime is better for disease control, but it costs money in lost production time.

During downtime, take these steps to protect the clean house:

Keep all doors and vents closed and locked. Only authorized personnel should enter.
Post a sign on the door stating that the house is in downtime and that entry is restricted.
Control rodents and wild birds. Check bait stations and traps regularly. Repair any holes or gaps that could let wildlife in.
Keep the area around the house clean. Mow grass, remove debris, and keep the perimeter free of standing water.
Do not move equipment or litter between houses during downtime.
If you must enter the house, use the same biosecurity protocols as during production. Wear clean boots and coveralls, and step through a disinfectant footbath.

Common Mistakes in Turnaround Cleaning

Even experienced producers make mistakes in the turnaround process. Here are the most common ones and how to avoid them.

Rushing the Dry Clean

The most common mistake is spending too little time on dry cleaning. It is tempting to move quickly to the washing step because it looks like progress. But dry cleaning is the foundation of the entire process. If you leave dust and debris on surfaces, the wash will not remove it all, and the disinfectant will not work. Budget the majority of your time for dry cleaning.

Using Disinfectant on a Dirty Surface

Disinfectants are not cleaners. They are inactivated by organic matter. Applying disinfectant to a surface that still has dust, manure, or biofilm will not kill the pathogens. The disinfectant will be neutralized before it can work. Always clean before you disinfect.

Skipping the Drying Step

Many producers apply disinfectant to wet surfaces because they are in a hurry. This dilutes the disinfectant and can reduce its effectiveness by 50 percent or more. It also leaves moisture in the house, which can promote pathogen growth. Allow the house to dry completely after washing and after disinfection.

Using the Wrong Disinfectant Concentration

More is not better when it comes to disinfectants. Using too high a concentration can leave toxic residues that harm the next flock. Using too low a concentration will not kill the pathogens. Follow the label exactly. Measure the disinfectant and the water carefully.

Overlooking Hidden Areas

Pathogens hide in cracks, crevices, and under equipment. If you only clean the visible surfaces, you will miss a significant portion of the pathogen load. Use a checklist to ensure you cover every area of the house, including the ceiling, the underside of equipment, and the space under slatted floors.

Forgetting the Anteroom and Entryways

The anteroom is a high-traffic area where contamination can enter the house. It must be cleaned and disinfected with the same rigor as the main house. Many producers focus on the bird area and forget the entryway, creating a weak link in biosecurity.

Not Documenting the Process

If you do not record what you did, you cannot prove that you did it. Documentation is important for internal management and for regulatory compliance. Keep a log of each cleaning event, including dates, products used, and any issues found.

Monitoring and Verification

How do you know that your cleaning and disinfection worked? Visual inspection is the first step, but it is not enough. Pathogens are invisible to the naked eye. A house can look clean and still harbor disease organisms.

Visual Inspection

Walk through the house after each step. Look for any remaining litter, dust, or organic matter. Check the corners, the edges of the floor, and the areas around equipment. If you see anything that looks dirty, clean it again before moving on.

Environmental Sampling

Environmental sampling is the most reliable way to verify that your cleaning and disinfection worked. The most common method is swabbing surfaces and testing for bacteria such as Salmonella or coliforms. Your integrator or a veterinary diagnostic laboratory can provide sampling supplies and testing services.

The standard protocol is to take swabs from multiple locations in the house after disinfection and before placement. Common sampling sites include:

Feed pans and feeder lines
Drinkers and water lines
Floor surfaces in the center and edges of the house
Walls at bird height
Ventilation inlets
The anteroom floor

If the samples come back positive for pathogens, you need to re-clean and re-disinfect the affected areas. This is much cheaper than placing birds into a contaminated house.

Water Line Sanitation

Do not forget the water system. Drinkers and water lines can harbor biofilm and pathogens. After cleaning the house, flush the water lines and treat them with a sanitizer. Your integrator may have a specific protocol for water line sanitation. Follow it exactly.

Recordkeeping

Keep a written record of every turnaround cleaning event. This record should include:

The date the house was depopulated
The date cleaning started and finished
The names of the crew members who did the work
The products used, including detergent and disinfectant names and lot numbers
The dilution rates and contact times
The results of any environmental sampling
The date the house was restocked

This record is useful for several reasons. It helps you track the effectiveness of your program over time. It provides evidence of due diligence if there is a disease outbreak. And it helps you identify patterns, such as recurring contamination in a specific area of the house.

When to Call a Veterinarian or Extension Agent

Most turnaround cleaning can be handled by the farm crew without outside help. However, there are situations where you should call in a professional.

Call your veterinarian or extension agent if:

You have a disease outbreak in the previous flock that you cannot explain or control
Environmental sampling shows persistent contamination despite repeated cleaning
You are unsure which disinfectant to use for a specific disease problem
You are planning a major renovation or change in your cleaning protocol
There is a reportable disease in your area, such as avian influenza, and you need guidance on enhanced biosecurity

A veterinarian can help you interpret sampling results and adjust your protocol. An extension agent can provide training for your crew and help you evaluate new products or techniques.

Frequently Asked Questions

How long should downtime be between flocks?

The minimum downtime recommended by most poultry companies is 7 to 14 days. Longer downtime is better for disease control. The downtime period starts after the house has been cleaned and disinfected, not after the last bird is removed. If you have a disease history in the house, extend the downtime to 14 to 21 days. The cost of lost production time is usually less than the cost of a disease outbreak in the next flock.

Can I reuse litter between flocks?

Some operations reuse litter with a partial cleanout system. This is a common practice in areas where bedding material is expensive or hard to source. However, litter reuse increases the pathogen load in the house and requires a more intensive litter treatment program. If you reuse litter, use a litter amendment to reduce ammonia and pathogens, and monitor the litter quality closely. If the litter is wet, caked, or contaminated with a disease outbreak, remove it completely.

What is the difference between cleaning and disinfection?

Cleaning is the physical removal of organic matter, dust, and debris. Disinfection is the application of a chemical product to kill pathogens. Cleaning must come first because organic matter protects pathogens from disinfectants. A house can be clean but not disinfected, but it cannot be disinfected without being clean first.

How do I choose a disinfectant for my poultry house?

Choose a disinfectant that is labeled for poultry house use and that is effective against the pathogens you are targeting. Consider the type of surface you are treating, the water quality, and the safety of the product for your crew. Rotate between two or three approved products to prevent resistance. Ask your integrator or veterinarian for a list of approved disinfectants for your operation.

Can I use bleach to disinfect my poultry house?

Bleach, or sodium hypochlorite, can be used as a disinfectant, but it has limitations. It is inactivated by organic matter, so the surface must be very clean before application. It is also corrosive to metal equipment and can be irritating to the skin and eyes. If you use bleach, follow the label dilution rate and rinse the surface after the required contact time. Many producers prefer other disinfectants that are less corrosive and more effective in the presence of residual organic matter.

How do I know if my cleaning and disinfection worked?

The best way to know is to take environmental samples after disinfection and before placement. Swab multiple locations in the house and send the samples to a diagnostic laboratory for testing. If the samples are negative for the pathogens you are testing, your program worked. If they are positive, you need to re-clean and re-disinfect the affected areas.

What personal protective equipment do I need for cleaning?

You need a respirator rated for dust and chemical vapors, goggles or a face shield, chemical-resistant gloves, and rubber boots. Wear coveralls that you can remove and wash after the job. When applying disinfectants, follow the safety instructions on the label. Some disinfectants produce fumes that are harmful if inhaled, so make sure the house is ventilated during application.

How do I clean the water lines between flocks?

Flush the water lines with clean water to remove debris, then fill the lines with a sanitizing solution. Use a poultry-specific water line sanitizer and follow the label instructions for concentration and contact time. After the contact time, flush the lines again with clean water before placing birds. Your integrator may have a specific protocol for water line sanitation. Follow it exactly.

Related Farming Guides

Poultry House Biosecurity: Carcass Disposal and Mortality Management

This section will be populated with links to other farming guides on this site, such as poultry house ventilation, litter management, and hatchery biosecurity. Check back soon for the full list of related resources.

Related Clinical & Scientific Guides

References

FAO Poultry Production: https://www.fao.org/poultry-production-products/en/
USDA APHIS Poultry Health: https://www.aphis.usda.gov/livestock-poultry-disease/avian
WOAH Avian Influenza: https://www.woah.org/en/disease/avian-influenza/
FAO Animal Production and Health: https://www.fao.org/animal-production/en/
WOAH (World Organisation for Animal Health): https://www.woah.org/en/home/

This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.