Highly Pathogenic Avian Influenza (HPAI) in Livestock

California Dairy Study Raises New Questions About How H5N1 Spreads

Fri, 08 May 2026 15:46:21 GMT

For months, discussions around H5N1 in dairy cattle have focused largely on infected milk and contaminated milking equipment. New research from California suggests the transmission picture may be far more complex.

In a study published this week in PLOS Biology , researchers investigating 14 H5N1-positive California dairies found evidence supporting several possible transmission pathways, including aerosols generated during milking and contamination within dairy wastewater systems. The study also identified signs of subclinical infection in some cows, raising new questions about how easily infected animals may be missed during outbreaks.

The findings add to growing evidence that the dairy environment itself may play a larger role in H5N1 transmission than previously recognized.

Infectious H5N1 Virus Detected in Dairy Parlor Air

One of the study’s most significant findings came from air sampling inside milking parlors.

Researchers collected aerosol samples during milking and detected not only viral RNA, but infectious H5N1 virus in some air samples. Viral material was also identified in exhaled breath collected from infected cattle.

Environmental sampling findings included:

Infectious virus recovered from parlor air samples and wastewater systems
Viral RNA identified in cow breath samples
Evidence of infection in some cows without obvious clinical signs

The distinction between viral RNA and infectious virus is important. Detecting RNA alone does not confirm viable virus is present, while recovery of infectious virus suggests aerosolized particles could potentially contribute to transmission.

The authors stopped short of concluding that airborne spread is a primary transmission route on dairies. However, the findings raise new questions about respiratory exposure risks in enclosed milking environments.

Milking parlors routinely generate aerosols through animal movement, splashing fluids, equipment use and high-pressure cleaning systems. The study suggests those environments may warrant closer attention during outbreak investigations and biosecurity planning.

The findings also have implications for worker safety. Since the U.S. dairy outbreak began, human infections linked to dairy cattle exposure have generally been mild, with conjunctivitis among the most commonly reported symptoms. Aerosol exposure during milking has remained a persistent concern for occupational health experts.

Wastewater Systems are a Possible H5N1 Exposure Route

Researchers also detected widespread contamination throughout dairy wastewater systems.

H5N1 viral RNA was identified in parlor drains, wastewater sumps, lagoons and reclaimed water systems. Infectious virus was recovered from some wastewater-associated samples as well. This finding may be particularly relevant for modern dairy operations, where reclaimed water is frequently reused for flushing and other management purposes.

The authors noted wastewater systems could create additional opportunities for virus movement within the farm environment through splashing, aerosol generation, contaminated surfaces and possible wildlife exposure. Wild birds have already played a major role in the global spread of H5N1. Contaminated wastewater or standing water could represent another point of interaction between dairies and wildlife populations.

The study does not establish wastewater systems as a major driver of transmission. However, it does suggest environmental contamination pathways may deserve more attention as researchers continue investigating how the virus behaves in dairy systems.

Some Infected Cows Showed Few Clinical Signs

The study also identified evidence of subclinical infection.

Some cows tested positive for H5N1 despite showing limited or no obvious clinical illness. In several cases, cows produced H5N1-positive milk without severe visible mastitis signs. Researchers also detected antibodies in animals without previously recognized disease.

Infection patterns within udders added another layer of complexity. Researchers noted some patterns did not fully align with expectations if transmission were occurring solely through contaminated milking equipment.

If milking equipment was the only major transmission route, infections between udder quarters would likely appear more predictable. Instead, the findings suggested additional exposure pathways may be involved.

These subclinical infections could complicate surveillance and outbreak detection efforts. Farms relying primarily on visibly sick cows may miss infected animals, particularly during the early stages of transmission. That has implications for testing strategies, animal movement decisions and outbreak response planning.

The findings also highlight how differently H5N1 behaves in cattle compared to poultry, where highly pathogenic avian influenza often causes rapid and severe disease.

Biosecurity Implications Continue to Evolve

The authors emphasized more research is needed to determine which transmission pathways are most influential on commercial dairies. Still, the study broadens the conversation around H5N1 biosecurity.

Early outbreak discussions focused heavily on milk contamination and fomite transmission through milking equipment. This study suggests aerosols, wastewater systems, environmental contamination and subclinical infections may also play a role.

That could influence future discussions around:

Parlor ventilation
PPE use during milking
Wastewater handling
Environmental sanitation
Surveillance strategies
Monitoring apparently healthy cows

The paper also underscores how much remains unknown about H5N1 adaptation in dairy cattle. Researchers identified mutations in some environmental samples that have previously been associated with mammalian adaptation, though the significance of those findings remains unclear.

This study offers an updated look at a disease situation that continues to evolve rapidly — and suggests transmission on dairies may involve a broader network of environmental exposures than initially believed.

APHIS Lifts Testing Requirements for H5N1 in Unaffected States

Mon, 27 Apr 2026 19:33:03 GMT

USDA’s Animal and Plant Health Inspection Service (APHIS) has issued updated guidance related to the April 2024 Federal Order that required testing of lactating dairy cattle before they move across State lines.

Effective immediately, lactating dairy cattle moving interstate from States with Unaffected State Status under the National Milk Testing Strategy are no longer required to be tested for highly pathogenic avian influenza (HPAI) H5N1 prior to movement.

View the updated guidance document .

Key Points

No testing required for lactating dairy cattle originating from States with Unaffected State Status under the National Milk Testing Strategy .
Unaffected State Status requires ongoing testing and surveillance activities to confirm the absence of HPAI in the State’s dairy herds.
This update follows a United States Animal Health Association (USAHA) resolution received in October 2025 and is expected to be widely supported by dairy and State animal health regulatory officials.
APHIS does not anticipate any impact on trade of cattle or beef/dairy products.

Public Health and Food Safety

The detection of HPAI H5N1 in lactating dairy cattle does not pose a risk to consumer health or compromise the safety of the commercial milk supply. Pasteurization effectively inactivates HPAI virus. Milk from affected animals is diverted or destroyed to prevent entry into the food supply. The U.S. Centers for Disease Control and Prevention (CDC) continues to consider the public health risk low.

The Importance of Biosecurity

USDA remains committed to working with State partners to monitor, investigate, and mitigate the spread of HPAI in livestock. This update does not change  USDA’s HPAI eradication strategy . Biosecurity is still key to mitigating the risk of disease introduction or spread between premises.

APHIS recommends  enhanced biosecurity measures  for all dairy farms. Producers should immediately report any livestock with clinical signs, or any unusual sick or dead wildlife, to their State veterinarian.

From the Parlor to the Perimeter: Protecting the Heart of American Dairy in 2026

Fri, 24 Apr 2026 12:47:14 GMT

2026 marks a defining moment for U.S. dairy producers. As biological threats evolve and new risks loom on the horizon, the industry’s focus has moved from the parlor to the perimeter. During a high-level panel at the High Plains Dairy Conference, leaders including Jason Lombard, Samantha Holeck and Dee Ellis addressed the biosecurity gap and the urgent need for a line of separation to safeguard the milk supply. This isn’t just a discussion about animal health; it’s a strategic deep dive into the risk management and business continuity required to keep the American dairy industry moving forward in a volatile world.

The Ghost in the Mammary Gland: The H5N1 Legacy

Lombard opened the discussion with a sobering retrospective on H5N1. What began as a bird flu headline in December 2021 has evolved into a complex, multi-species challenge that has fundamentally altered the dairy landscape.

Lombard’s timeline showed the relentless march of the virus. From the first detections in wild birds in the Carolinas to the jump into commercial turkeys in 2022, the industry watched with wary eyes. But 2024 was the year the ground shifted. The B3.13 genotype emerged in dairy cattle in Texas and Kansas, eventually spreading to multiple states and even jumping to alpacas and swine. By late 2025, new genotypes like D1.1 were being detected in Arizona, Nevada and Wisconsin.

The most jarring revelation, however, was the visual evidence of where the virus hides. Lombard shared microscopic images of the mammary gland, where sialic acid receptors — the locks the virus keys into — glowed red, and the virus itself (AIV) glowed yellow.

“It’s in the milk,” Lombard stated flatly.

The spread isn’t just about a bird dropping a feather in a feed bunk. The data now shows a web of transmission: the movement of cattle, the movement of people and even the breathing of the herd. Most concerning for the 2026 outlook is the role of aerosols and peridomestic birds like swallows, pigeons and starlings. We are fighting a ghost that can be carried on a breeze or the back of a common filth fly.

The Emerging Nightmare: New World Screwworm

While the industry is still reeling from H5N1, Holeck introduced a threat that sounds like the plot of a horror movie but carries devastating economic reality: New World screwworm (NWS).

For decades, the U.S. has been protected by the “Darien Gap” and a massive eradication effort that pushed the screwworm south into Central America. But in 2026, the map is changing. Holeck shared a situational update showing thousands of active cases in Mexico, with some pushing dangerously close to the U.S. border.

“This will change the way we do business,” Holeck warned.

If NWS crosses the border, the implications are immediate and severe. We are talking about total movement restrictions, intensive live-animal inspections and the potential for lost trade. Unlike a virus, NWS is a parasite — a fly that lays eggs in open wounds, where larvae then consume living tissue. Holeck’s toolbox for 2026 isn’t just about vaccinations; it’s about management. It’s about preventing injuries, adjusting management practices to keep wounds clean, and a hyper-vigilant remove and dispose protocol for larvae.

The Reality of the Gap: Data from the Barn Floor

Farm Journal conducted its own research on research launched at the 2025 Milk Business Conference. The research illustrates a significant biosecurity gap between large and small operations.

The data showed that while 71% of producers have cameras in their milking parlors, only 38% have defined entrances with clear signage for designated vehicles like milk and feed trucks. The discrepancy becomes even sharper when looking at herd size. Larger dairies are significantly more likely to have designated employee parking (+23%) and cameras at facility entrances (+32%) compared to dairies with fewer than 1,000 cows.

The producer’s dilemma is real: ROI versus risk. On a smaller operation, a $20,000 security and sanitation upgrade can feel like a mountain, especially when the threat hasn’t hit your zip code yet. But as the panel emphasized, biosecurity is like insurance — you only realize its value when it’s too late.

One of the most telling statistics from the survey was that 25% of producers admitted they “don’t control and limit access” to feed storage areas. In an era where H5N1 and other diseases can be carried by wildlife and birds into the very food the cows eat, this is a glaring vulnerability.

The Blueprint: Drawing the Line of Separation

Ellis provided the how-to for the future: The Secure Milk Supply (SMS) Plan. This isn’t just a binder that sits on a shelf; it is a voluntary, science-based framework designed to ensure business continuity during a disease outbreak.

The core of the SMS plan is the line of separation (LOS). Ellis shared sample dairy maps that looked more like tactical military charts than farm layouts. The LOS creates a clear clean/dirty boundary.

The Dirty Side: Where public roads, non-essential deliveries and rendering trucks reside.
The Clean Side: The protected area where cows live, eat and are milked.

Implementing an SMS plan means identifying specific LOS access points, creating vehicle cleaning and disinfecting stations and establishing strict logs for every person and animal that crosses that line.

“Don’t sacrifice good for perfect,” Ellis advised. “Every SMS plan is unique. The key is to start. Post your map where every employee can see it every day. Make the clean/dirty concept part of your farm’s culture.”

The Biosecurity Umbrella

Biosecurity can feel like a cloud of acronyms and diseases: BVD, TB, Johne’s, Mycoplasma and now H5N1 and NWS.

Biosecurity isn’t easy. It’s tedious. It’s expensive. And it’s often invisible.

As an industry, we must move away from a reactive posture and toward a proactive, fortified model of production. Whether it’s a million-dollar operation in the Texas Panhandle or a 100-cow family farm in Wisconsin, the line of separation is the same.

The call to action for the industry is the same for every operation across the U.S.:

Assemble your team and review protocols now — before the challenge hits.
Look at your perimeter and sanitation, especially in feed and transport areas.
Support each other. If you serve producers, help them find the resources to make these investments.

While we may be facing genotypes and parasites that generations before us never dreamed of, we now have the science, the data and the collective will to protect the milk supply.

The 2026 revolution isn’t just about how much milk we can produce; it’s about how well we can protect it. And in that mission, we are all behind the wheel together.

The Invisible Perimeter: High-Tech Biosecurity in the Age of Bird Flu

Tue, 24 Mar 2026 12:10:01 GMT

In the heart of Tulare, Calif., Tyler Ribeiro is conducting an experiment in “mediocrity-free” farming. As a fourth-generation dairyman at Rib-Arrow Dairy, he has seen the industry evolve through a century of challenges. But today, the stakes have shifted. While the Central Valley sun and volatile markets remain constant pressures, an invisible threat moved to the forefront of the dairy conversation last year: Highly Pathogenic Avian Influenza (HPAI), or bird flu.

For a dairy milking 1,500 cows, the emergence of H5N1 in dairy herds represents a fundamental shift in how animal well-being is defined. It is no longer just about comfort and production; it is about the rigorous defense of the milk supply itself. At Rib-Arrow, the philosophy of being tech-forward has become the farm’s strongest shield against this mounting biosecurity threat.

Early Detection: The Digital First Line of Defense

The battle against a viral threat like bird flu begins with early detection. Ribeiro’s implementation of Nedap SmartSight vision technology and activity monitoring collars provides a level of granular oversight that was impossible for previous generations. While these systems were primarily installed to monitor locomotion — reducing the lameness incident rate in first lactation cows from 6% to 2% — their value in a biosecurity crisis is immense.

“A cow starts hurting long before we can see it with our eyes,” Ribeiro notes.

Tyler Ribeiro

(Rib-Arrow Dairy)

This same principle applies to viral illness. Before a cow shows clinical signs of HPAI, such as a drop in milk production or lethargy, her data — captured 24/7 in the NedapNow cloud platform — begins to tell a story. By catching subtle changes in activity or movement early, high-tech dairies can isolate animals and implement quarantine protocols before a virus has the chance to move through the entire herd. In the era of bird flu, data is the difference between a minor incident and a total operation shutdown.

Automated Perimeter

Biosecurity is often compromised by the movement of people and equipment. Rib-Arrow’s lean toward automation directly mitigates this risk. The HoofStrong automated foot baths, which have been in place since 2015, are a prime example. Because the system is fully self-contained and self-cleaning, it reduces the need for constant employee intervention and chemical handling.

(Rib-Arrow Dairy )

Similarly, Ribeiro’s three-pronged approach to fly control — using automated flash-sprays, baits and parasitic wasps — limits the presence of pests that can carry pathogens across the dairy. By automating these dirty work tasks, the dairy ensures protocols are executed with 100% consistency, creating a closed-loop environment where the risk of cross-contamination is significantly lowered.

Protect the Pipeline: A Strategic View

The challenges faced by dairies like Rib-Arrow are the focal point of the upcoming 2026 High Plains Dairy Conference in Amarillo. A critical addition to the lineup is the panel “Protecting the Milk Supply,” featuring experts like Dee Ellis from Texas A&M and New Mexico state veterinarian Samantha Holeck. Their work bridges the gap between the regulatory requirements of state-level safety and the daily reality of the parlor.

As Ribeiro notes: “I hate it when people show up and say, ‘You’re doing a great job.’ Show me where I’m missing.”

This mindset is essential for modern biosecurity. Protecting the pipeline requires producers to work alongside data scientists like Jason Lombard of Colorado State University’s AgNext to understand the science of staying open, which involves analyzing every touch point on the farm — from how calves are transported to how manure is managed — to ensure business continuity in the face of a biosecurity event.

(Rib-Arrow Dairy)

Reputation and Resilience

The final layer of defense against bird flu is communication. For a dairy like Rib-Arrow, transparency and clear communication are vital.

Ribeiro’s “data nerd” approach allows him to provide a real-time truth about his herd’s health. Whether it is downloading thousands of cells of data to analyze with AI or checking his phone app for a cow’s locomotion score, he is equipped to prove the resilience of his operation.

As the road through 2026 and beyond is paved, the goal remains the same as it was 100 years ago: healthy cows and a sustainable business. The difference now is the eye in the sky and the mountain of data are the tools ensuring the next generation of the Ribeiro family is still standing — and profitable — no matter what biological threats the world throws at them.

Could Lasers Help Keep Birds Out of the Feedbunk?

Fri, 13 Mar 2026 21:09:49 GMT

Where there’s feed on the farm, birds usually follow. These nuisance pests aren’t only an eyesore, but they can cause real damage in terms of feed loss and biosecurity risk.

For pigeons, starlings and sparrows, grain piles, commodity bays and feedbunks quickly become an all-you-can-eat buffet. In fact, a flock of 10,000 birds can consume up to 500 lb. of feed daily. While these critters certainly aren’t a new problem for dairies, a newer technology has emerged that may offer another way to manage bird pressure. And the interesting part? It involves laser beams.

A New Approach to Bird Control

The system, developed by iChase, uses cameras to identify birds in the area. Once a bird has been spotted, a green laser beam slowly sweeps across the ground, walls or feedbunk to spook the bird away. Because poultry rely heavily on their eyesight, the moving laser looks to them like something solid getting closer. Their instinct is to fly away from it.

According to the company, the system can be installed above feedbunks or mounted on farm structures to help discourage birds from gathering. As the laser repeatedly moves through the same spaces, birds begin to view the area as unpredictable and uncomfortable. Eventually, many avoid the area altogether.

The idea is similar to other deterrents producers have tried over the years, but the constantly moving light is designed to be harder for birds to get used to. Traditional approaches like predator decoys and reflective tape can work at first, but birds often adapt once they realize the threat isn’t real.

Another feature that helps the technology stand out is coverage. iChase states that a single unit can cover a large area, which may make it useful in places like silage bunkers or commodity barns where birds tend to gather.

Interest in the technology has also grown outside of dairy. Airports and warehouses have also used laser deterrents to reduce birds in sensitive areas. As the equipment becomes more available, agricultre companies are starting to explore how it might fit into other livestock operations as well. As farms continue looking for practical ways to protect feed and maintain cleaner facilities, tools like these are starting to draw interest.

Does Bird Flu Have an Effect on Cow Fertility?

Fri, 06 Feb 2026 20:52:17 GMT

When highly pathogenic avian influenza (HPAI) first hit U.S. dairies, it threw the industry into unfamiliar territory. With so many unknowns, the immediate focus was on slowing the spread and caring for the cows that were affected.

Now, with more of the puzzle pieces coming together, researchers are beginning to step back and look at the bigger picture, examining how the virus affects cows not only in the days and weeks after infection, but what it may mean for their health and performance long after.

On a recent episode of “The Dairy Podcast Show”, Jennifer Spencer and Juan Pinedo, Extension dairy specialists with Texas A&M, came together to better understand what this virus is doing to reproduction — and if infected cows will be paying the price for years.

What Does HPAI Mean for Cow Fertility?

Spencer and Pinedo are just starting to study HPAI’s long-term effects, and their work is one of the first to measure how it may impact reproduction in U.S. dairy herds. Early signs point to a real effect on reproductive performance, particularly in younger animals, though the science is still evolving.

“We really want to know if it does impact reproduction,” Spencer says. “We want to let the producers know so they can understand if they might have to cull heavier to make sure that they’re managing this and replacing the cows in a timely manner — for sustainability of the herd and also to help maintain or improve their profitability.”

Like all major health events, HPAI is predicted to have an impact on cow fertility or pregnancy loss. But for Spencer and Pinedo, they are trying to figure out to what degree.

“We know that when cows get sick, they shift their energy toward fighting an infection rather than reproducing,” Spencer explains. “If these cattle that are infected with HPAI are having reduced milk production, feed intake and rumination, then there’s a high probability it’s impacting reproductive efficiency and their performance.”

Pinedo adds this pattern isn’t unique to HPAI, but still worth studying.

“Just like with any other systemic disease, having a detrimental effect in repro performance is something that we will expect,” Pinedo explains.

Dig Into Herd Data

In March 2025, Spencer’s team received rapid-response funding from USDA APHIS to study how HPAI affects reproduction in dairy herds. They designed a retrospective observational study, analyzing on-farm records from January 2021 through each herd’s HPAI outbreak and beyond.

“We’re looking at data from January 2021 until they had an HPAI outbreak,” Spencer says. “How we’re determining that is based not just on what the producer says, but by also analyzing the records and looking for that drastic drop in milk production, because that’s kind of the overall sign when they had an HPAI outbreak.”

To give the team a wide view of how HPAI is affecting herds in different settings, the project spans across three dairy regions with five to 10 dairies per region. These areas include the:

South Central
Western U.S.
Pacific Northwest

“We want to get information from different environments to have a better idea of the geographical differences, and what they deal with heat-stress-wise, or the feed availability,” Spencer says. “This will give us a 30,000' view of what is happening.”

A Hit on Heifers

While the full analysis is still in progress, the team has already taken a close look at one South Central dairy, and the early patterns are raising important questions in heifers. The study found conception rates dropped during the outbreak year but appeared to rebound the following year.

“For heifers, they actually had about a 5% decrease in their conception rates during 2024 from March until December, but that appears to go back up in 2025,” Spencer reports.

Pinedo added specific figures to put the changes into perspective.

“There was a 52% conception rate, and they dropped during the outbreak to 45%. The year after, they came back to 50%,” he notes.

These numbers show that while conception rates began to recover after the outbreak, they didn’t fully return to pre-HPAI levels. Spencer notes heifers needed more services per conception, suggesting the virus may have lingering effects on reproductive efficiency.

“For heifers, we saw an increase in services per conception, but they’ve remained higher. They went from about a 1.5 up to like 2, 2.2 number of times bred for their heifers, and it’s continuing into 2025,” she adds.

Spencer admits that wasn’t what they expected.

“We didn’t think that heifers would be impacted,” she says.

Complicating things further, some of the heifers in question were born to cows infected late in gestation.

“Some of those heifers were actually from cows that were in their third trimester of their pregnancy, so that may be a contributing factor,” Spencer adds. “There’s so many moving parts in it.”

How Are Cows Being Impacted?

For cows, the pattern is more complex. Unlike heifers, which showed a relatively clear dip and rebound in conception rates, mature cows showed more varied responses to HPAI. Some herds experienced noticeable declines during the outbreak, while others were less affected.

“We did see conception rates appeared to decrease in all of the lactations,” Spencer notes. “But for the first and third and greater lactations, they seem to be going back up, whereas the second lactation seems to be kind of having a harder time rebounding.”

Those second-lactation cows are noteworthy because many were first-lactation animals during the outbreak itself.

“It seems as if perhaps a first-lactation animal, which you might think would be more resilient to recover, maybe, is having more longer-term effects on at least reproduction, as opposed to older cattle,” Pinedo adds.

These unexpected patterns have the researchers taking a closer look at the number to try and determine why younger animals are taking a bigger reproductive hit.

How Much Should We Read Into Early HPAI Data?

While the data is eye-opening, both researchers are quick to point out that the findings are still early, and there’s a lot they don’t yet know.

“This is research that is at the very early stages, and it’s a retrospective observational study,” Pinedo emphasizes. “You really want to control confounders; it’s nothing that we could jump into conclusions [about] right now.”

He lists the kinds of changes every producer lives with year to year:

“You have bull genetics that will have changed, repro program that will have changed, feed that will have changed, heat abatement technologies, so many confounders that affect repro that have to be controlled,” he says.

Spencer sees the same complexity in the field of research.

“What if they changed a breeder? Or what if they started using precision technologies on their heifers, so their heat detection rate went up? These are things we have to take into consideration,” she says.

For now, the research is still in its early stages, but the data suggest HPAI does have reproductive effects worth paying attention to, especially in younger animals. As the team continues to analyze records and track herd performance, these early insights can help producers keep a closer eye on animals who were impacted by the virus and make more informed decisions for the long-term health and fertility of their herds.

California Reopens Dairy Cattle Shows Following HPAI Ban

Tue, 20 Jan 2026 17:01:46 GMT

After more than a year on the sidelines, dairy cattle and poultry shows are returning to California fairgrounds. The California Department of Food and Agriculture (CDFA) has lifted its statewide ban on exhibitions, clearing the way for shows to resume.

The restriction was put in place at the beginning of 2025 as the state tracked the spread of H5N1 Highly Pathogenic Avian Influenza (HPAI). After months of surveillance and review, state officials now say conditions have improved enough to allow a cautious restart.

According to the department, the decision was based on ongoing monitoring of H5N1 activity across the state, analysis of viral trend data and consultation with state and federal epidemiologists. After a detailed review, the CDFA has determined the risk associated with poultry and dairy cattle exhibitions has declined enough to allow shows to resume, provided enhanced safeguards remain in place.

State officials pointed to stronger biosecurity awareness across the industry as a factor in the decision. Over the past year, producers and exhibitors have become more familiar with transmission risks and prevention strategies, helping reduce overall exposure concerns.

As fair season draws closer, CDFA says the move gives clearer direction to youth livestock programs, breeders and exhibitors who have spent months unsure whether animals would make it back to the show ring.

While the ban has been lifted, fairgrounds and exhibitors are being urged to stay cautious. Enhanced biosecurity measures, routine health checks and careful animal handling are still recommended, especially in high-traffic areas. State monitoring of H5N1 will continue throughout the exhibition season, with officials working alongside fair organizers and animal owners as events resume.

How to Keep Birds Out of Barns

Mon, 29 Dec 2025 22:52:35 GMT

A few birds might not seem like a big deal, but unmanaged populations can quickly create real problems on a dairy. From feed loss to biosecurity concerns, birds can put herd health and even profitability at risk.

While there’s no perfect solution for ridding dairies of birds, control starts with understanding what’s legally allowed, taking timely action and using multiple strategies consistently. Starting early and applying consistent measures helps prevent issues before they escalate and creates conditions that make barns less appealing to these nuisance pests.

How Much Damage Can Birds Cause?

Bird-related damage and feed waste can be substantial, particularly when large flocks are present. Research from the University of Kentucky indicates a single European starling consumes approximately 0.0625 lb. of feed per day. While that amount might not seem like a lot, it can add up quickly. A flock of 10,000 birds can consume up to 500 lb. of feed daily, resulting in significant losses over time.

According to Matthew Springer, wildlife specialist, and Donna Amaral-Phillips, dairy Extension specialist, the impact extends beyond feed loss. Birds often target high-nutrient components of the ration, leaving behind an unbalanced mix. This inconsistency can negatively affect intake and animal performance, even when feed delivery is otherwise well managed.

Bird droppings are another headache. Manure from roosting birds can contaminate feed bunks, waters and barn surfaces, increasing the risk of disease transmission. When they have easy access to feed and housing areas, they can create added biosecurity challenges. Birds are known carriers of E. coli and Salmonella and can potentially carry highly pathogenic avian influenza (HPAI), or bird flu. Working to keep these pests out of barns can help protect herd health and reduce the risk of disease.

Know the Legal Limits

Before taking steps to manage birds, producers need to understand the legal requirements that govern control methods. Bird control is regulated by state and federal law, so it is important to check with your state wildlife division before creating a control plan.

Many bird species are legally protected, so it’s important to know the rules before taking action. It is illegal to kill or harm protected birds without a permit, and you cannot disturb nests that contain eggs or young. If your control measures could affect these species, you’ll need a Migratory Bird Depredation Permit from the U.S. Fish and Wildlife Service, often obtained with help from USDA-APHIS Wildlife Services. Starting with your state wildlife agency can save headaches later and keep your plan within the rules.

Start With Prevention and Timing

Bird control works best when prevention starts early and is adjusted throughout the year. Even during winter, acting quickly can keep birds from settling in and establishing roosts that are harder to remove later.

Focus winter prevention efforts on:

Sealing gaps around vents, eaves and rooflines
Keeping feed areas clean and covered
Installing plastic strip curtains on doors to limit entry

Birds tend to stick around when they find an easy meal, so limiting access to feed is essential. To reduce feed-related attractants:

Clean up spilled feed daily
Store minerals and additives in sealed bins when possible
Keep commodity bays tidy and sweep up loose feed regularly

Water can also attract birds. If they can drink or bathe in waterers, they are more likely to stay.

Prevent birds from perching on waterer edges
Adjust water levels so birds can’t easily reach the water
Clean waterers frequently to remove debris and droppings

Exclusion and Netting

Keeping birds out of barns is one of the most effective long-term strategies, but it takes planning and persistence. Because barns need airflow and room for equipment, completely sealing them isn’t always practical. Instead, focus on improving the spots birds are most likely to use.

Some practical ways to keep birds out include:

Closing gaps around vents, eaves and rooflines
Hanging plastic strip curtains on doors to limit entry
Using netting in areas where birds tend to roost or nest

Plastic strip curtains are especially helpful because they let people and equipment pass through while keeping birds out. Any openings larger than half an inch around vents, eaves and lofts should be blocked with wood, metal or wire mesh. These steps won’t get rid of every bird, but they can go a long way toward reducing roosting and nesting in barns.

Make Roosting Sites Uncomfortable

Birds prefer flat surfaces for perching, so changing those surfaces can make barns less inviting.

Ways to discourage roosting inside the barn:

Alter ledges to angles of 60 degrees or greater
Add angled wood or metal sheathing to problem areas
Install porcupine wire on ledges and rails

Outside the barn, you can also make your property less appealing by:

Thinning tree branches near buildings to remove perch sites
Reducing wind protection that shelters birds, encouraging them to move elsewhere

Scare Tactics Require Persistence

Visual scare devices and distress calls can help discourage birds, but they must be changed regularly. Birds quickly become accustomed to static deterrents. Combining visual and sound deterrents and rotating them throughout the year improves effectiveness.

Examples of scare tactics include:

• Reflective tape or colored flags
• Flashing or revolving lights
• Distress calls or AM/FM radios
• Wind chimes or loud noises
• Replicas of hawks, owls or snakes

A Year-Round Commitment

Birds are a persistent nuisance on farms, and their presence can affect everything from feed quality to overall herd health. Unfortunately, there is no perfect solution to eliminate them completely, so managing their numbers and keeping them out of barns requires attention year-round. The most effective programs start early, use a mix of strategies and adjust seasonally as bird activity changes.

First Case of Avian Flu Detected in Wisconsin Dairy Herd

Sun, 14 Dec 2025 19:40:26 GMT

A case of highly pathogenic avian influenza (HPAI) has been detected in a dairy herd in Dodge County, Wisconsin, the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) announced Sunday. This marks the first confirmed detection of the virus in dairy cattle in the state.

Dodge County, Wisconsin

(USDA)

The herd was identified through routine National Milk Testing Strategy screening, not the surveillance required for moving cattle across state lines. The affected farm has been quarantined, and any cattle showing signs of illness are being separated for treatment.

Bird flu has already been detected in poultry flocks in Wisconsin. On Dec. 9, state officials reported HPAI in a flock in Marquette County, which is just one county away from the affected dairy herd.

HPAI in dairy cattle has been documented in the U.S. before, with the first detections reported in March 2024 in dairy herds in Texas and Kansas. Since then, there have been more than 1,000 confirmed cases across 18 states, primarily through targeted testing and monitoring programs. While the pace of new detections has slowed in recent months, one additional confirmed case has been reported in California within the past 30 days, indicating the virus is still a threat.

HPAI Confirmed Cases in the Last 30 Days

(USDA)

Total HPAI Confirmed Cases

(USDA)

A Wake-Up Call for Dairy Biosecurity

The Wisconsin case comes as new research from Farm Journal highlights ongoing gaps in dairy biosecurity practices nationwide. A survey of more than 300 dairy producers, presented at the MILK Business Conference, found that while many operations report having biosecurity plans in place, consistent implementation and regular review remain a challenge.

According to the survey, 68% of farms with at least 250 cows say they have a biosecurity plan, yet 34% of those producers acknowledge they do not routinely review or update it. The findings point to vulnerabilities at a time when disease threats such as HPAI, New World screwworm and bovine spongiform encephalopathy continue to raise concern across the livestock sector.

(Farm Journal)

“We need biosecurity efforts to be more impactful at the ground level,” said Kirk Ramsey, professional services veterinarian with Neogen, who reviewed the survey results. “Not only to prevent major outbreaks, but also to protect employees and families from what could be carried home every day.”

As emerging diseases continue to challenge dairy operations, the research reinforces the importance of consistent, practical biosecurity measures to reduce risk and protect herd health.

What are the Symptoms of HPAI in Dairy Cattle?

As monitoring continues, officials are urging producers to stay alert for early signs of illness within their herds, as prompt detection and response remain key to limiting further spread. Signs of HPAI include:

Drop in milk production
Loss of appetite
Changes in manure consistency
Thickened or colostrum-like milk
Low-grade fever

State officials are monitoring the situation and working closely with the farm to contain the virus and prevent further spread. DATCP emphasized there is no concern for the safety of the commercial milk supply, as pasteurization eliminates the virus. The CDC considers the human health risk low.

Read more on HPAI in dairy:

More Funding Going to Tackle HPAI H5N1, Egg Imports are Now Underway to Stabilize Supply

Thu, 20 Mar 2025 20:35:10 GMT

On Thursday morning, USDA Secretary Brooke Rollins gave an update on progress the Trump administration is making on the five-prong strategy it unveiled Feb. 26 to combat avian influenza virus type A (H5N1).

Speaking to industry stakeholders, media and offices of elected officials, Rollins focused on the administration’s work to lower egg prices and improve supply, while also emphasizing the importance of biosecurity in protecting U.S. poultry flocks from the virus.

Regarding egg prices, she said wholesale prices are down nearly 50% from their peak in late February from $8.53 then to $4.08 currently.

However, Rollins said she realizes that wholesale prices don’t automatically show up as reductions in retail prices.

“I know for some of us who are shopping that we’ve seen egg prices drop immediately, which has been true for me. But then we’ll hear from people in other parts of the country where they have yet to see that reduction on their grocery store shelf.”

With Easter just a few weeks away, she acknowledged that egg demand is always “unusually high during the season,” and that egg prices could potentially move back up.

To help address the egg shortage, Rollins noted that shell egg exports have declined by 8%, “keeping more eggs in the U.S. and lowering prices.”

In addition, the Trump administration is allowing egg imports as a temporary measure to stabilize prices and supply. Rollins’ chief of staff Kailee Buller said this measure would likely be discontinued once those measures were achieved.

USDA Focuses On Biosecurity For Poultry Operations
Rollins said biosecurity in poultry flocks will continue to be a major part of the Trump administration’s plan to address H5N1, moving forward.

“Our pilot programs have proven that biosecurity is the most important thing our farmers can do to protect our flocks against the disease, at least right now,” she said.

The USDA is working closely, she said, with its federal partners including the U.S. Department of Health and Human Services (HHS), Centers for Disease Control (CDC), National Institutes of Health (NIH), and the Food and Drug Administration (FDA) to “combat avian flu as a unified federal family.”

On Wednesday, USDA announced it is expanding the availability of its biosecurity assessments to commercial poultry producers.

“These assessments, which were previously available on a limited basis have been extremely successful in improving biosecurity on individual premises and preventing the introduction or spread of avian influenza,” Rollins said.

While USDA is exploring the viability of vaccinating poultry for H5N1, she said the use of any vaccine for poultry or any animal species has not been authorized at this time.

“I know there has been some misreporting on that,” Rollins said. “The day we rolled out the plan, I actually talked about the fact that we’re not ready to vaccinate. We need to do some more research, and so that has not changed, but I do look forward to this next process of learning more about getting more research done and perhaps seeing what makes sense for the country moving forward, once that is concluded.”

Dairy Is Not Part Of USDA’s Primary H5N1 Focus
No information was offered during the conference call to address the issue of H5N1 in dairy cattle or other livestock or animal species.

Mike Watson, administrator of USDA-APHIS, said right now USDA is focused on the poultry vaccine.

“We’re looking for a vaccine that has sterilizing immunity but also an opportunity for us to have different introduction methods for the vaccine right now, as injections are the only possibility,” he said. “We need new tools, whether it’s water based, aerosol based, those kind of things. We’re looking for manufacturers to really look at what those options might be, to really provide us with a vaccine that matches the current strain but also is highly effective. And again, this is really focused on poultry.”

Buller said there is already quite a bit of research at USDA on the topic in dairy.

“Please rest assured, we are thinking of you all (in dairy). We know you all are impacted. But for this particular strategy, we have been hyper-focused on the poultry side. USDA has separate work streams as we’re working through this on the cattle and dairy side.”

One of the media asked whether Sec. Rollins had talked further with HHS Sec. Robert F. Kennedy Jr. regarding his idea of letting H5N1 burn through poultry flocks to identify birds that might have immunity or show resistance to the virus.

Buller answered the question, as Rollins had stepped away from the call. “I have not been engaged specifically with those conversations with the Secretary and Secretary Kennedy,” she said. “They are talking very regularly and you are aligned on the approach, but in terms of that specific topic, there’s no further light I can shed on that at this time.”

Assessments Available To Poultry Operations
USDA is offering two different, free, voluntary biosecurity assessments for poultry operations not currently affected by HPAI.

The first is a wildlife biosecurity assessment. The second is a general biosecurity assessment. Poultry producers can request one or both of these free assessments.

Per the wildlife biosecurity assessment, Rollins said USDA will conduct on-farm assessments at poultry facilities and provide recommendations to producers for facility repairs and wildlife management techniques. The assessments include a series of regular engagements, including wildlife hazard identification surveys, wildlife abundance surveys and wildlife management on the premises.

“USDA has assessed approximately 130 facilities to date (in 2025), and plans on doing significantly more moving forward and expanding that program,” she said.

For the general biosecurity assessment, USDA will work with poultry producers to review biosecurity plans and physical measures.

“This is a proactive resource for premises that are outside of avian flu control areas to identify and mitigate potential biosecurity gaps,” she said.

Funding Is Ramped Up To Address HPAI In Poultry
The USDA announced on Thursday that up to $100 million in funding will be available to support projects on avian influenza, prevention, therapeutics, vaccines and research.

“USDA will invest up to $100 million in these projects, which will identify and foster innovative solutions to fight avian flu and directly support American producers,” Rollins said during the conference call.

Funding is available through a competitive process to for-profit organizations, including manufacturers of vaccines, biologics and therapeutics, as well as states, universities, livestock producer organizations and other eligible entities, she noted.

USDA will prioritize one or more of the following. First, it will support the development of novel therapeutics to address HPAI in poultry. Second, it will support research to further understand the risk pathways of avian influenza for producers and to inform improved biosecurity and response strategies.

“Let me just say, as a quick aside, I’ve had multiples and multiples and multiples of conversations with some of our chicken farmers across the country —many of them have been highly successful at not having the bird flu infect their populations,” Rollins said. “Better understanding of risk pathways and realizing what best practices are is a big part of (this work).”

The third focus is on the development of novel vaccines to protect poultry from H5N1 while promoting biosecurity.

“That will all be part of the research funding opportunity that we announced about an hour and a half ago,” Rollins said.

USDA will test the efficacy of therapeutic interventions to prevent the virus and treat infected flocks.

“USDA, in consultation with HHS, has already had multiple conversations with Secretary Kennedy and leaders in the NIH and CDC, but will also be exploring prevention strategies to promote biosecurity in agriculture and in humans, to ensure limited impact on American farmers,” Rollins noted.

USDA is offering a webinar to assist interested applicants in learning more about the funding opportunity and how to submit a proposal on Tuesday, April 1 at 12 p.m. Eastern. No details on how to participate in the webinar have been communicated yet.

“As we try to do everything under this president and here at USDA, we will be as fast and efficient and effective as we can possibly be, working around the clock,” Rollins said.

Buller added that Sec. Rollins and her staff will continue to host update calls regularly.

“It’s very important to Sec. Rollins that we are showing progress on this five-prong plan and being honest and open with the public about what we’re up to and the progress and potential challenges that we have ahead,” Buller said. “We have an open door here, and we remain open to having conversations and hearing from stakeholders.”