Good Biosecurity Reduces Risk of Avian Influenza in Poultry and Dairy

By Mary Keena and Miranda Meehan

Spring migration is currently underway. Now is the time for those with poultry and dairy to ramp up biosecurity efforts, according to Miranda Meehan, North Dakota State University Extension livestock environmental stewardship specialist. North Dakota lies within a primary migration corridor for waterfowl, with millions of birds migrating through the state.

Highly pathogenic avian influenza (HPAI) is a disease carried by wild birds and affects domestic birds and mammals. Avian influenza is caused by the influenza Type A virus, commonly known as influenza A. The virus is shed in infected birds' feces and respiratory secretions and can survive for weeks in cool, damp environments.

Positive cases of HPAI in backyard poultry, commercial poultry and dairy herds are currently occurring across the U.S.

One of the first clinical signs of HPAI in poultry is sudden, unexplained death. Most poultry cases report a decline in water and feed consumption. Decreased egg production and depression in layers may be another sign that birds are not feeling well. Purple or dry combs, quieter-than-usual behavior, frequent laying down and swelling around the eyes are other symptoms birds may experience.

The virus isn’t fatal for most dairy cattle. The first sign in dairy cattle is often a sudden drop in milk production. Other common symptoms include low appetite, fever, lethargy and thickened or discolored milk.

The best way to reduce the potential for transmission of HPAI, says Meehan, is to minimize interaction between wildlife and domestic animals. Wild birds are primary transmission vectors to your domestic poultry and dairy. However, any animal that enters the property, including pets and other animals, may track the virus or bring an infected bird onto the property.

NDSU Extension specialists — such as Mary Keena, livestock environmental management specialist — have developed tips for reducing HPAI transmission.

To reduce transmission between wildlife and domestic animals, NDSU Extension recommends the following:

• If possible, keep animals housed until the risk for transmission has decreased. Nonlethal methods to deter wildlife are available on the U.S. Department of Agriculture wildlife damage webpage: https://www.aphis.usda.gov/wildlife-services/about/nonlethal.
• Reduce the attractiveness for wildlife to stop at your place by cleaning up litter and spilled feed around your domestic animal housing.
• If you come in contact with or handle wildlife, change into clean clothes, wash your hands and disinfect your footwear before contact with domestic animals.
• Report sick or deceased wildlife to the North Dakota Game and Fish Department at https://gf.nd.gov/wildlife/diseases/mortality-report.
• If you need to handle or dispose of carcasses to reduce potential interactions, follow the appropriate procedures outlined on the NDSU Extension website: ndsu.ag/ndsuhpai.

The best defense against HPAI is having a biosecurity plan in place.

“As a dairy or poultry owner, it is your job to create a line of separation between your clean animals and the potential unclean issues that wildlife or visitors may bring,” says Keena.

To reduce transmission between domestic animals, NDSU Extension recommends the following:

• Keep your distance. Restrict access to your property and your animals. Allow contact from people who care for your birds but minimize visitors.
• Minimize interactions. Do not allow poultry and livestock to share water sources, feedstuffs or living environments with each other or wildlife.
• Keep a clean environment. Wear clean clothes, scrub your shoes with disinfectant and wash your hands thoroughly before and after caring for your poultry or livestock. Clean and disinfect tools and equipment that come into contact with your poultry or livestock or their feces.
• Do not haul disease home. Clean and disinfect car and truck tires if you have been near other poultry or bird owners, such as at feed stores. New birds should be kept separate from your flock for at least 30 days.
• Do not borrow disease from your neighbor. Do not share lawn and garden equipment, tools or bird supplies with your neighbor or other flock owners.

More information about biosecurity can be found on the USDA’s Defend the Flock webpage: www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/avian/defend-the-flock-program.

Products from dairy cattle and poultry testing positive for HPAI are prohibited by law from entering the marketplace. Poultry and poultry products are safe to eat, and proper handling and cooking is always advised. Pasteurization of dairy products has been documented to kill the virus. Raw dairy products should not be produced from milk produced from animals exhibiting avian influenza symptoms.

In 2025, there have been no positive HPAI cases in domestic poultry or birds in North Dakota. Early detection is important to prevent the spread of disease. Monitor animals closely and report sick animals to your local veterinarian. If you do not have a local veterinarian, contact the North Dakota State Veterinarian’s office at 701-328-2655.