Herd Health

Garlic in the Water Trough? What New Research Means for Fly Control in Cattle

Mon, 13 Apr 2026 15:19:27 GMT

For decades, producers across the U.S. and Canada have used garlic-infused minerals or salt as a natural fly control strategy. The biological rationale is straightforward: sulfur-containing compounds from garlic are absorbed, circulated and released through the skin to repel flies.

But when tested under field conditions, the results have been inconsistent.

A two-year Canadian grazing study evaluating garlic-infused trace mineral salt illustrates that variability. In one group, cattle receiving garlic had 47% fewer flies and 41% fewer defensive behaviors compared to controls. In another group, however, no significant difference was observed, despite the same supplementation strategy.

The authors point to several possible drivers, including environmental conditions, genetic differences and variation in supplement intake.

Other controlled work in the U.S. has produced weaker signals. In a 14-week field study in Louisiana, cattle consuming garlic through mineral only achieved about a 25% reduction in horn fly numbers, a level described as not meaningful relative to expected control standards.

Taken together, the North American literature points to a consistent pattern: garlic shows biological potential, but results are not reliable enough to stand alone as a primary control tool.

Intake May Be The Limiting Factor

Both of these studies relied on free-choice mineral or salt delivery, where intake can vary widely between animals and across time. Even when average consumption appears adequate, dose per head per day is not controlled with free-choice delivery, making consistent exposure difficult to achieve.

In practice, this does more than reduce efficacy — it makes outcomes unpredictable at the herd level.

This shifts the conversation from “Does garlic work?” to a more practical question: Can it be delivered consistently enough to produce a repeatable effect?

Delivering Organosulfur Compounds Through Water

A 2026 Australian study published in Tropical Animal Health and Production evaluated that question under commercial conditions. Instead of relying on free-choice intake, researchers delivered garlic-derived organosulfur compounds through drinking water in a grazing beef herd.

This approach directly addresses one of the most consistent limitations identified in North American work: variable intake across animals.

The study followed 266 beef cows split into treatment and control groups with the same stocking density with no changes to routine management. Both groups received the same base ration over the 16-week experimental period, but the treatment group received the garlic-derived supplement through water.

With intake standardized at the herd level, a clearer signal emerged:

Treatment group: ~80% reduction in fly counts within two weeks
Control group: ~20% increase over the same period
By week four:
- Treated: ~110 flies/head
- Control: ~350 flies/head
Seasonal pressure increased fly numbers in both groups:
- Treated: ~550% increase from baseline
- Control: ~6,500% increase

Behavioral Response Aligns With Reduced Fly Pressure

Behavioral indicators followed the same pattern as fly counts. Defensive behaviors — including tail flicking, head tossing and stamping — increased in both groups as fly pressure rose. However, the increase was substantially lower in treated cattle (68%) compared to controls (186%), indicating reduced irritation under similar conditions.

These behavioral changes reflect more than visible discomfort; they are tied to grazing time, stress and overall performance.

Relevance to Fly Control in North American Systems

While the study focused on buffalo flies, the implications extend to horn flies, the primary ectoparasite in U.S. and Canadian grazing systems.

Both species:

Remain on the host for most of their life cycle
Feed frequently on blood
Trigger similar behavioral and production responses

The underlying mechanism — repellency via metabolized organosulfur compounds — is expected to translate across fly species.

Where This Fits in Practice

Water-based delivery of garlic-derived compounds may have a role as part of an integrated fly control strategy, particularly in:

Extensive grazing systems
Herds with inconsistent mineral intake
Operations where labor limits handling-based interventions

North American research has shown garlic-based fly control can produce reductions in some settings, but results have been inconsistent. Across studies, variation in intake has been a recurring limitation.

This new study suggests when intake is controlled through water, the same compounds may produce a more consistent response at the herd level. At the same time, the findings should be interpreted within the study’s constraints. The trial lacked replication, did not measure individual intake and did not assess compound stability in water.

This work emphasizes how a product is delivered can be just as important as what is delivered when it comes to real-world performance.

Can Phytogenics Shield Your Herd from Acidosis and Heat Stress?

Wed, 18 Mar 2026 17:27:08 GMT

Heat stress is intensifying, subacute ruminal acidosis remains widespread and dairy producers are under increasing pressure to maintain performance while reducing reliance on medications. Many of these challenges share a common thread: the gut.

From microbial imbalance to compromised intestinal barrier function, disruptions in gut health can trigger inflammation, reduced production and poorer welfare outcomes. Herd health is increasingly approached through the lens of gut integrity and systemic inflammation, and interest in nutritional tools that support digestive stability is growing.

Nicole Reisinger, senior scientist with dsm-Firmenich Animal Health and Nutrition in Austria, studies how feed additives influence gut biology, biomarkers and animal health. In a recent conversation on the “ Dairy Podcast Show ”, she described emerging evidence that plant-derived compounds may help cows cope with physiological stress affecting the digestive tract. Phytogenic feed additives may support gut health by stabilizing rumen microbial populations, strengthening intestinal barrier function and reducing inflammatory responses.

What Are Phytogenic Feed Additives for Cattle?

Phytogenic feed additives are gaining attention as part of this shift toward preventative herd health. Derived from plants, they include essential oils, herbs, spices and plant extracts, often combined into blends designed to produce complementary biological effects.

Reisinger notes part of their appeal lies in the biological roles these compounds already play in nature.

“The nice thing is that they’re kind of designed by nature. Those compounds all have a purpose in nature, so it’s quite logical that they would also have an impact on animals,” Reisinger says.

Rather than relying on a single compound, many phytogenic products combine multiple ingredients designed to influence several physiological pathways.

“It might be that one substance is not enough. You need to combine them in the right way so that you really have the effect you are interested in,” she explains.

These combinations may influence microbial activity, inflammatory pathways and digestive processes simultaneously — an approach that may be useful when addressing multifactorial health challenges in cattle.

Can Phytogenic Feed Additives Improve Rumen Health During Acidosis?

Subacute ruminal acidosis (SARA) remains one of the most common nutritional disorders in high-producing dairy herds. While ration formulation and feed management remain central to prevention, a growing body of research is beginning to show how phytogenic blends may influence rumen function during acidosis challenges.

This includes controlled work from the University of Veterinary Medicine Vienna, where phytogenic blends containing compounds such as menthol, thymol and eugenol have been shown to improve rumen pH, stabilize fermentation patterns and reduce inflammatory markers during SARA challenges.

“For acidosis, there were quite a few positive effects we could see. It really started with feed intake and then also saliva production and buffering the rumen pH. We had an influence on the pH of the saliva, but then also on the microbiome, which is very essential,” Reisinger says.

What recent research suggests:

A recent meta-analysis of essential oils in ruminants found these compounds can shift fermentation pathways, reduce ammonia production and improve efficiency without compromising animal health.

These effects are consistent with observed changes in rumen stability and feed utilization during acidosis challenges, where microbial modulation appears to play a central role in maintaining digestive function.

How Does Heat Stress Affect Gut Health in Cattle?

Beyond rumen acidosis, heat stress presents another major physiological challenge for cattle, particularly as extreme temperatures become more frequent and severe.

Heat stress can affect the digestive system in several ways, including:

Reduced blood flow to the intestinal tract
Increased gut permeability (leaky gut)
Movement of endotoxins into circulation
Activation of systemic inflammatory responses

“Phytogenics are essential for this kind of challenge because they can really impact gut permeability. They can really help to strengthen the gut barrier, and this is one of the major things we see with heat stress,” Reisinger says.

What recent research suggests:

Phytogenic blends can improve feed efficiency and nutrient utilization in lactating dairy cows under summer conditions without negatively affecting milk yield, even when dry matter intake is reduced.

By helping maintain intestinal integrity, phytogenics may improve the animal’s ability to cope with environmental stress.

Where Do Phytogenic Feed Additives Fit in Herd Health Management?

Despite the potential benefits, feed additives alone cannot solve complex herd health problems.

“It’s always a combination of nutrition as well as management. We also need to be honest that it’s not the feed additive alone,” Reisinger says.

Sound ration formulation, transition cow management and environmental controls such as ventilation and cooling remain essential. Phytogenic additives may serve as another tool to help cows remain resilient when stressors arise.

What recent research suggests:

In grazing dairy cows , phytogenic blends can lead to improvements in rumen fermentation and milk production comparable to monensin, supporting their role as a viable alternative.

What Is the Future of Phytogenic Feed Additives in Cattle?

Interest in phytogenic feed additives continues to grow as the dairy industry looks for preventative approaches that support productivity and animal welfare.

“I think phytogenics are a good choice for the future, especially thinking about staying a bit more into the natural support,” Reisinger says. “Consumers are probably interested in us looking more into biological support than giving medication.”

Many of the dairy cow’s most significant health challenges begin in the digestive tract. Supporting gut stability may be central to helping cows remain healthy and resilient in the face of both nutritional and environmental stress.

From Good to Best: Record Keeping That Actually Gets Used

Wed, 04 Mar 2026 17:15:12 GMT

Most farms are not short on data. They are short on recorded, usable data.

Some have spreadsheets, some use software, some have their treatment sheets printed. But unless the numbers are prioritized, cleaned up and reviewed, they rarely change management decisions.

As Bethany Dado-Senn, calf and heifer technical specialist with Vita Plus, puts it: “The cows don’t lie. They’re trying to tell us all the time what is going on. But if we don’t have any way to measure their outputs and the results, then we can’t do anything about it.”

The real challenge is not collecting everything, but collecting what matters and building a system veterinarians and producers can sustain together.

A practical framework helps: prioritize, essentialize and systemize.

1. Prioritize: Decide What Actually Matters

Before adding another metric or installing another program, start with focus.

“We need to start small. We need to identify what our top priority is to start,” says Kelly Sporer, farm data consultant with Cornerstone Ag Management. “We can’t look at everything and say ‘We’re just going to start, we’re going to dive in, we’re going to do it all.’”

Trying to track everything almost guarantees that nothing will be done well.

Instead, identify the two or three numbers that will move the herd forward right now. Those priorities will differ by farm.

“Everything that we do, we have to think about that customer, that relationship or that client, and what they’re trying to do and where they are now,” Dado-Senn says.

For example, a veterinarian might help a producer prioritize:

Fresh cow losses
Calf morbidity trends
Pregnancy rate
Early-lactation culling

The goal is focus, not complexity. Once priorities are clear, progress becomes measurable.

2. Essentialize: Remove What Gets in the Way

“A lot of the dairies we work with are not collecting completely comprehensive data,” Sporer says.

Even when farms try to track data, the system often breaks down. When records are entered inconsistently, the story they tell can be misleading.

Dado-Senn recalls once reviewing records that appeared to show catastrophic losses: “I’ll look back and it’ll look like we had a mass die-off one month, but it was really just the one month they finally cleaned their records up.”

Incomplete data makes analysis nearly impossible.

“If we have incomplete and inaccurate data, I can do a whole lot for you as far as data analysis, but we can’t do very much in ways of recommendations or changing anything in management,” Dado-Senn says.

And if the data is never reviewed with the intention of making changes, motivation disappears.

“If nobody is looking at it, that data is completely useless to the farm that’s spending valuable time collecting it,” Sporer says.

Essentializing can help with this by removing friction.

That might involve:

Standardizing health event terms
Assigning one person responsible for data entry
Recording events the day they happen
Simplifying treatment sheets
Reviewing numbers regularly with the herd team

The veterinarian plays an important role here, helping define case definitions, treatment thresholds and consistent terminology so the records reflect real clinical events.

3. Systemize: Move From Good to Better to Best

Record keeping does not need to be perfect. The key is building a system that improves over time.

“This is not about being super robust. It’s about starting somewhere,” Sporer reminds.

GOOD — The basics are written down

Deaths recorded somewhere
Pregnancy checks entered
Treatments written down

BETTER — Records become organized

Health events recorded consistently
Reasons for death or culling included
Data entered into herd software

BEST — Data drives decisions

Trends reviewed by age or stage of lactation
Protocol changes evaluated before and after
Health and reproduction trends analyzed over time

The goal is simple: When management changes, records help answer one question: Did it work?

That is when records stop being paperwork and start becoming management tools.

Importantly, not every farm needs to operate at “best” immediately. Progress from inconsistent notes to reliable digital entry is already a major improvement.

5 Record-Keeping Mistakes That Make Data Useless

Collecting data takes time. But when records are incomplete or inconsistent, the information becomes nearly impossible to use.

Recording data months later
Events should be recorded as close to real time as possible.
Using vague or inconsistent health terms
Different staff describing the same condition differently makes data nearly impossible to analyze.
Collecting data no one reviews
Review meetings reinforce why records matter.
Incomplete herd inventory
Animals still listed in the system long after leaving the herd distort nearly every performance report.
Trying to track everything at once
Strong record systems develop step by step.

Partnership Turns Numbers Into Action

Record keeping works best when it is collaborative.

“When everybody is working toward the same goal, which is the success of the farm, there’s no room for pointing fingers,” Dado-Senn says.

The veterinarian–producer partnership is central to building that culture.

Veterinarians translate trends into management insights. Producers provide the operational context that explains what is happening in the barn.

Together they decide what to track, how to track it and when to review it.

Without that collaboration, records sit unused. With it, they guide decisions from calf to cow.

When farms prioritize what matters, remove unnecessary barriers and build simple systems together, record keeping moves from good to better to best. That’s when the numbers start working for the herd.

The 3-Year Bet: Navigating Semen Choices and Herd Dynamics

Thu, 05 Feb 2026 15:54:07 GMT

In the high-stakes world of dairy management, a single decision made in the breeding lane can echo through a farm’s balance sheet for years. When a producer stands with a straw of semen in hand, they aren’t just breeding a cow; they are making a three-year financial and biological investment.

On a recent episode of the “Dairy Health Blackbelt Podcast,” Daryl Nydam, a professor of dairy health and production at Cornell University, sat down with Craig McConnel, an associate professor and director of veterinary medicine extension at Washington State University’s College of Veterinary Medicine , to discuss the complex intersection of herd dynamics, semen selection and long-term sustainability. Nydam’s message to producers is clear: While short-term cash flow is tempting, the long-term health of the dairy depends on maintaining the right number of replacements to ensure every stall is occupied by an efficient animal.

3-Year Investment Cycle

The fundamental challenge of replacement planning is the significant lead time required to bring a new animal into the milking string. As Nydam points out, a breeding decision made today involves a nine-month gestation period followed by approximately two years of growth before that animal begins producing milk.

“It’s really hard to predict your replacement needs three years forward,” Nydam explains. “Are we going to invest in sexed semen so we have enough replacements in three years, or are we going to try to shortcut that for quick cash flow?”

This shortcut usually involves breeding dairy cows to beef bulls to produce a high-value crossbred calf. While this provides an immediate sizable check at the farm gate, it reduces the pool of future replacements, effectively locking the producer into their current herd structure for years to come.

The ‘Black Calf’ Bubble

The rise of the beef-on-dairy market has fundamentally shifted the math for many producers. What began as a $500 premium for a crossbred calf has climbed to $750, then $1,000 and even higher in some regions.

“I don’t know where this bubble is going to go, but those things markedly influence herd replacement rates and therefore the dynamics of the herd,” Nydam says.

The temptation of immediate cash can lead to overbreeding to beef. When producers curtail their replacement pipeline to capture calf checks, they lose their most important management tool: the ability to cull. Nydam argues that if you don’t have an available heifer, you cannot make the most efficient cow-by-cow decisions; you are forced to keep underperforming or unhealthy cows simply to keep the stalls full.

The Culling Conundrum

From a veterinary perspective, culling is often seen through the lens of health: replacing a cow because she is sick or open. However, Nydam encourages a more management-centric view.

“If you show up on any dairy on any day, can you find one cow that you would like to replace that day?” Nydam says. “It’s really rare that I go to a dairy and say there are no cows here that I want to replace today.”

The ability to act on that instinct depends entirely on having a heifer ready to calve. As Nydam puts it: “A sick cow today doesn’t cause a heifer to calve two years ago.” If the replacement wasn’t planned for 36 months in advance, the producer is stuck with the “40-pound cow” that is dragging down the herd’s average efficiency.

Sustainability and the ‘Maintenance Dilution’

Beyond the immediate economics, the balance of replacements has a significant impact on a farm’s environmental footprint. Sustainability in dairy is largely a game of diluting maintenance costs.

A lactating cow requires a significant amount of energy and dry-matter intake just to maintain her body before she produces a single drop of milk. High-producing, efficient cows dilute that maintenance tax over a larger volume of milk.

“Having a few extra heifers is actually less resource-intensive versus not having the most efficiently productive lactating cows,” Nydam says. He adds that while a yearling heifer eats 20-25 lb. of dry matter, a lactating cow eats 55-60 lb. Keeping an inefficient cow because you lack a replacement heifer is a far greater waste of resources than raising a small surplus of heifers to ensure only the best cows remain in the herd.

Balancing Cash Flow with Strategy

Nydam acknowledges that “cash is king” and the revenue from crossbred calves is a vital part of the modern dairy business model. However, he cautions against sacrificing long-term profitability for short-term liquidity.

The goal for 2026 and beyond should be a strategic middle ground. By using tools to predict future replacement needs and understanding the marginal milk value required to offset a beef-cross calf check, producers can fine-tune their herd structure.

Ultimately, long-term sustainability is about having the most efficient animal in every slot on the dairy, all the time. Achieving that requires looking past today’s calf check and planning for the milk check of 2028.

Your Next Read:
Will Beef-on-Dairy Help Rebuild America’s Record-Low Cattle Numbers?

Inside a Simulated HPAI Outbreak in a Dairy Herd

Fri, 16 Jan 2026 19:28:32 GMT

In spring 2020, U.S. dairy producers were forced to dump millions of pounds of milk when the system around them failed. Schools closed, institutional buyers disappeared, processing plants couldn’t pivot and the disconnect between production and demand became painfully clear. That experience raised a critical question: Could similar system-wide disruptions happen again, driven not by markets but by disease?

That question helped drive a new proof-of-concept project from the Western Institute for Food Safety and Security (WIFSS) at UC Davis: a simulation model designed to examine what happens when H5N1 highly pathogenic avian influenza (HPAI) enters a dairy herd.

“This was more a proof of concept,” says David Goldenberg, food safety and security training coordinator for WIFSS at UC Davis. “Can we develop a model that would mimic a dairy farm and the resulting impacts [HPAI] would have not only on the farm but also elsewhere and down the road?”

Rather than attempting to predict the next outbreak, their goal was to understand what an outbreak would look like on a single dairy and how its impacts unfold over time.

What the Model Simulated

The team based their simulation on a small dairy herd of roughly 260 cows with the following assumptions:

No animals were purchased from outside sources; replacements were born into the herd
Labor, equipment and milking infrastructure functioned normally
Cows were assumed healthy apart from H5N1 infection
Milk from infected cows was discarded

Further, reinfections were not modeled, and the analysis focused on acute infection rather than chronic disease.

Speed of Spread Mattered More than Severity

One of the clearest lessons from the simulation was how fast H5N1 spreads through a herd might matter more than how sick individual cows appear.

The model evaluated low, medium and high infectivity scenarios. In high-infectivity cases, nearly the entire herd became sick within about 30 days. That rapid clustering overwhelmed treatment capacity, increasing the risk of dehydration, delayed care and mortality. This wasn’t because the disease was more severe but because too many animals required attention at once.

“That’s a tremendous effort to simultaneously try to treat every cow in your herd at the same exact time due to limited resources,” says Nelson Alfaro Rivas, simulation consultant with MOSIMTEC. “Unfortunately, some of the cows might succumb just because of dehydration from the disease just because you don’t have an unlimited number of veterinarians to try and hydrate the cows as they’re sick.”

In lower-infectivity scenarios, illness spread more slowly, peaking later and involving fewer animals simultaneously. The contrast underscored why early isolation, movement control and disease recognition can fundamentally change outcomes.

Milk Loss Didn’t End When Cows Recovered

Even when cows clinically recovered, milk production did not bounce back quickly.

The simulation assumed infected cows experienced either a 15% or 30% reduction in milk yield for the remainder of their lactation, figures drawn from field observations. In high-infectivity, worst-case scenarios, total milk production across the herd fell sharply within the first month.

Over time, those losses accumulated. In the most severe scenarios, the herd produced approximately 25% less milk over the modeled period compared with an uninfected baseline. Perhaps more striking, herd-level production did not return to baseline for almost a year, long after the active outbreak had resolved.

“How long does it take to recover from something like this?” Rivas asks. “All the cows were recovered by day 26, but what you don’t really see is that the herd that got infected doesn’t really recover and produce the same amount of milk as the non-infected herd until almost 300 days later.”

This gap matters not only for producers but also reframes recovery as an extended process rather than a clinical endpoint.

Recovery Didn’t Mean Economic Recovery

Because dairies run on thin margins, sustained milk loss drove decisions beyond treatment and recovery. Cows producing well below expectation after infection were more likely to be removed from the herd, even if they survived the disease itself.

“At the end of the day, farms are businesses, and you can’t keep an underproducing and therefore unprofitable cow,” Rivas says.

The model reinforced a familiar reality: Profitability, not survival alone, determines herd composition after disease events.

Where Biosecurity Fits

Biosecurity practices were not explicitly modeled as individual actions. Instead, their effects were represented indirectly through changes in infectivity. Lower infectivity scenarios approximated the benefit of practices such as isolating sick cows, cleaning equipment and controlling farm access.

Those measures come with costs — labor, time and disruption — but the simulation showed even modest reductions in spread speed dramatically altered outcomes. The model did not attempt to assign dollar values to biosecurity steps, but it made clear why reducing infectivity yields outsized returns.

Why This Matters Now

What this model ultimately provides is a clearer sense of risk timing, not new disease facts. By compressing complex outbreak dynamics into a single on-farm view, it shows how quickly routine management assumptions can be tested once disease pressure rises, particularly when multiple animals require attention at the same time. The practical consequence is that delays in recognition or response can carry operational costs that aren’t immediately visible.

The take away is not alarm but foresight. Decisions around monitoring, separation and communication that are made early shape how manageable an outbreak remains and how disruptive its aftermath becomes. By visualizing those downstream effects in advance, the model offers a way to stress-test response strategies before they’re needed, helping dairies prepare for uncertainty rather than react to it.

New Leadership to Take on Key Animal Health Roles at USDA

Tue, 13 Jan 2026 19:23:03 GMT

USDA announced major leadership changes within the Animal and Plant Health Inspection Service (APHIS). Michael Watson, APHIS administrator, will retire at the end of January after decades of distinguished service, and Rosemary Sifford, deputy administrator for veterinary services and U.S. chief veterinary officer, has also retired from federal service after a similarly notable career.

Dedicated Public Servants

Watson’s notable career reflects his unwavering commitment to safeguarding U.S. agriculture, building strong partnerships with states and stakeholders and mentoring future leaders. Beginning his USDA career in 1994 as a plant pathologist with the Agricultural Research Service, he later held key leadership roles across multiple APHIS programs. APHIS says Watson consistently championed science-based policy, ensuring APHIS decisions were grounded in rigorous data and research to protect U.S. agriculture and maintain public trust. His legacy is one of collaboration, integrity and dedication to public service.

Sifford began her USDA career in 1997 as a Saul T. Wilson Scholar and held numerous roles across APHIS. Under her leadership and guidance, APHIS advanced major animal health efforts, including combatting highly pathogenic avian influenza — with unprecedented detections in dairy cattle — and strengthening preparedness and response for New World screwworm. APHIS says her direction ensured these efforts were grounded in science-based policy, supported by field-ready guidance, and delivered with transparent stakeholder engagement. A steadfast champion of practical, proven biosecurity, she worked hard to protect animal health nationwide.

“Dr. Watson and Dr. Sifford are dedicated public servants and we greatly appreciate their time at USDA, serving American farmers and ranchers, and protecting the national security of the U.S. I am so grateful for their extended service to support the Trump administration during such a critical time for American agriculture,” says U.S. Secretary of Agriculture Brooke L. Rollins in a news release. “The team at APHIS plays a critical role in protecting our food supply from foreign pests like the New World screwworm, as well as fighting diseases like bird flu. I have the utmost confidence in Ms. Moore, Dr. Huddleston and Dr. Dijab in continuing this critical mission and defending American agriculture.”

New Leadership

Starting Feb. 1, Kelly Moore will serve as acting administrator. Moore is currently acting chief operating officer for USDA’s marketing and regulatory programs mission area, and acting deputy administrator of marketing and regulatory programs business services.

“She brings extensive operational leadership experience and results-driven management, including a strong foundation of discipline from her prior service in the U.S. Marine Corps,” APHIS reports. “Ms. Moore is highly adept at guiding organizations through periods of change and transition and driving efficiency, compliance and innovation at scale — critical to APHIS’s mission during this pivotal time.”

Effective immediately, Dr. Alan Huddleston will serve as acting U.S. chief veterinary officer. With deep expertise in epidemiology and program development, he will represent U.S. animal health priorities internationally and maintain strong engagement with states and industry.

(USDA APHIS)

Dudley Hoskins, under secretary for marketing and regulatory programs, says their leadership and commitment to collaboration strengthened APHIS and the nation’s animal and plant health systems.

“These are consequential changes at a pivotal moment for the agency, and I am confident that Ms. Moore, Dr. Huddleston, and Dr. Dijab will not only serve as steady hands for program continuity but will lead APHIS into a new era,” Hoskins says.

To ensure continuity during this transition, APHIS veterinary services associate deputy administrator Adis Dijab will continue to provide operational oversight of veterinary services.

“APHIS operations continue uninterrupted, guided by science-based policies, strong stakeholder engagement and experienced acting leaders to ensure program continuity,” APHIS reports. “APHIS remains steadfast in its mission to protect the health, welfare and value of our Nation’s plants, animals, and natural resources — continuing to deliver solutions and essential services that safeguard U.S. agriculture and support stakeholders nationwide.”

Managing Disease Risk Before It Arrives

Wed, 24 Dec 2025 14:33:17 GMT

As cattle move more frequently across regions and production systems, veterinarians are increasingly tasked with helping clients prevent the introduction of infectious disease that can persist silently and erode herd performance over time. In many cases, the greatest risk is not an outbreak, but the gradual establishment of a pathogen that is difficult or impossible to eliminate once introduced.

While biosecurity includes people, equipment and environmental considerations, animal movement remains the most important driver of infectious disease risk. This was the central topic of discussion on a recent episode of Dr. Dan Thomson’s “DocTalk.”

Why Animal Movement Drives Disease Risk

“Our biggest risk is going to come from the animal itself,” said Dr. Dustin Loy, director of the Veterinary Diagnostic Center at the University of Nebraska-Lincoln. “This is going to be something that’s going to move with the animal and be transmitted from that animal to the rest of the herd.”

Transport and commingling represent peak risk periods for disease transmission. The stressors associated with hauling, dietary change and social disruption can suppress immune function and allow latent or subclinical infections to emerge. When cattle with different exposure histories mix, pathogens can spread rapidly through immunologically naive groups.

“If we can make sure that those animals we’re sourcing have a herd health program, they’ve had those calfhood vaccines and the boosters, that they have a high level of immunity to the common diseases, that’s going to really help us prevent some amount of problems,” Loy says.

However, while vaccination programs reduce risk, they are insufficient for a number of diseases of biosecurity concern. Performing diagnostic testing before animals are purchased or moved can help identify infected animals before they enter herds.

Diseases That Define Biosecurity Risk

Several diseases are consistently central to cattle biosecurity planning due to their transition dynamics, diagnostic challenges, and long-term herd impact.

Johne’s Disease

Johne’s disease remains one of the most difficult infections to control as clinical signs don’t appear until years after the animal has been infected.

“The challenge with Johne’s is that those calves are infected when they’re a month or less in age,” Loy says. “We’re not able to test those calves until they’re at least a year and a half, and usually we want to wait until they’re two or three years old just to know if they’re infected. And so that’s a real diagnostic challenge: being able to identify those animals early.”

Due to this prolonged subclinical phase, infected animals can shed Mycobacterium avium subspecies paratuberculosis, contaminating the environment and exposing young calves. Clinical signs include progressive weight loss, decreased production and chronic diarrhea, with no effective treatment. Because diagnostic sensitivity improves with age, Loy says fecal testing at pregnancy checks provides a practical surveillance point for identifying infected adults and limiting further transmission.

Anaplasmosis

Anaplasmosis is increasingly detected outside historically endemic regions, likely due to cattle movement. Caused by Anaplasma marginale, this disease is transmitted mechanically by ticks, biting flies and contaminated instruments. Calves exposed early often develop immunity with minimal clinical disease, but infection in naive cattle can cause severe anemia, abortions and sudden death.

Importantly, vectors can only transmit the organism if infected animals are present, making the testing of incoming cattle a key biosecurity step to prevent establishing a persistent reservoir within a herd.

“If we don’t have animals with anaplasmosis coming into the area, the ticks don’t transmit anaplasmosis,” Thomson says.

Bovine Viral Diarrhea (BVD)

Despite routine vaccination, BVD remains a biosecurity concern due to persistently infected (PI) animals.

“You get cows that are infected when they’re pregnant, they infect the fetus, and then the fetus does not have an immune response to the virus, so that calf is born infected. It never clears the virus and continues to shed that throughout its life,” Loy explains.

PI animals serve as powerful sources of infection, contributing to reproductive failure, immunosuppression, respiratory disease and poor performance, even in vaccinated herds. Ear-notch testing is a practical, cost-effective method for identifying PI animals prior to commingling.

Bovine Leukosis Virus (BLV)

BLV transmission occurs through blood transfer, including needles, equipment and biting insects. While many infected cattle remain asymptomatic, a subset develop lymphoma later in life, reducing longevity and productivity. Screening animals intended for long-term retention, such as breeding stock or embryo recipients, can help prevent gradual spread within expanding herds.

Core Biosecurity Questions for Veterinarians

When advising clients on cattle purchases or movements, consider asking the following questions:

Where are the animals coming from and have they been commingled with cattle from other sources?
Are these animals being moved between groups, pastures or regions with different disease exposure histories?
Do the source animals have an established herd health program, including appropriate core vaccinations and boosters?
Can diagnostic testing be used before or shortly after movement to reduce quarantine time and uncertainty?

Effective biosecurity does not eliminate all disease risk. Instead, it allows for the identification of the most consequential threats early, before they become entrenched, expensive and difficult to control.

Why is H5N1 Showing Up in Cattle?

Thu, 18 Dec 2025 14:02:00 GMT

As H5N1 continues to be detected in U.S. dairy cattle, new research shows some modern bird flu viruses are genetically better equipped to infect bovine cells than earlier strains, helping explain why cattle are now part of the outbreak.

Highly pathogenic avian influenza (HPAI) is no longer just an avian problem. Recent detections of H5N1 in dairy cattle, including the latest confirmed case in a Wisconsin herd , have elevated concern among veterinarians, producers and animal health authorities. According to USDA, HPAI has been detected in dairy herds in at least 18 states since March 2024, with milk testing serving as a routine detection pathway.

A newly published Nature Communications study led by scientists at the MRC–University of Glasgow Center for Virus Research provides critical insight into why certain H5N1 viruses are now capable of infecting cattle and highlights that some recent H5N1 variants are better at infecting cow cells and mammary tissues than older viruses. This suggests recent spillover events are not random accidents but might reflect viral genetic traits that support infection in cattle.

“Our work shows that different bird flu viruses have very different abilities to infect cow cells and tissues,” says Professor Massimo Palmarini, from both the Erasmus Medical Center and the MRC–University of Glasgow Center for Virus Research. “While the strain currently spreading in U.S. cattle is clearly the best adapted so far, there are other bird viruses that could potentially infect cows if given the chance.”

Key Findings Veterinarians Should Know

H5N1’s ability to infect cattle varies by viral lineage and the outbreak clade stands out

Researchers evaluated a wide range of historical and contemporary H5N1 viruses in bovine cell systems. The results were clear: Replication efficiency in bovine cells differed substantially between strains. Earlier H5N1 viruses often showed limited replication, while variants of the current outbreak from clade 2.3.4.4b, including genotypes B3.13 and D1.1, performed significantly better.

Why it matters: This variability helps explain why cattle infections are being detected now, after decades of HPAI circulation in birds. This also aligns closely with what field veterinarians are seeing: dairy cows developing clinical signs, such as reduced milk production and abnormal milk, often in the absence of severe respiratory disease.

The phenotypes of the reassortant viruses described in the study using either bovine or human cells and restriction factors as indicated.

(Nature Communications (2025). DOI: 10.1038/s41467-025-67234-1)

Internal genes, not just surface proteins, drive adaptation

The study highlights that synergistic interactions among internal gene segments, including viral polymerase complex and non-structural genes, play a critical role in determining how well H5N1 replicated in bovine cells. This shifts the focus away from viral surface protein hemagglutinin alone.

Why it matters: Viral evolution that improves replication in cattle could occur without obvious changes to classical avian influenza red flags, complicating surveillance and risk assessment.

Adaptation does not mean inevitability, but it raises the stakes

The authors stop short of suggesting H5N1 is becoming a cattle-adapted virus. However, they do demonstrate a biological pathway for improved compatibility with bovine hosts.

Why it matters: If H5N1 continues circulating in cattle, even transiently, it carries opportunities for viral maintenance, farm-level spread, and additional spillover events.

Connecting Lab Findings to Field Observations

These results provide a critical biological framework for the unusual epidemiology seen in recent cattle detections. The finding that modern H5N1 variants replicate efficiently in bovine mammary cells explains why dairy herds, and not beef, have been the focus of this outbreak and why milk has emerged as a vital surveillance sample.

This shift in viral tropism is directly reflected in the field: Infections are typically identified not by respiratory distress but by sudden drops in milk yield and abnormal milk consistency. While commercial pasteurization ensures the general milk supply remains safe, the high viral loads in raw milk highlight a pressing need for enhanced biosecurity within the milking environment. Ultimately, when production anomalies coincide with local avian influenza activity, H5N1 testing should be considered an essential component of the diagnostic workup.

First Case of Avian Flu Detected in Wisconsin Dairy Herd

Sun, 14 Dec 2025 21:35:02 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:

New Research Exposes Stagnant Biosecurity Efforts in the U.S. Dairy Industry

Tue, 02 Dec 2025 19:20:34 GMT

When it comes to biosecurity, U.S. dairy farmers are more reactive than proactive and some neglect the basics, making operations vulnerable to evolving disease threats, according to new research released Tuesday at MILK Business Conference .

The study found farm hygiene and herd health aren’t top of mind on all farms and one-third of farms don’t proactively review their biosecurity plans indicating a potential lack of ongoing commitment or adaptation.

There is a silver lining: More than 70% of large dairies say they are already working on improvements, meaning some in the industry are prioritizing biosecurity.

The recent research conducted by Farm Journal, which surveyed more than 300 dairy producers, looks at trends and potential vulnerabilities that might be affecting dairy farms nationwide. As disease challenges such as highly pathogenic avian influenza (H5N1), New World screwworm (NWS) and bovine spongiform encephalopathy (BSE) continue to mount, biosecurity remains a critical concern for the industry.

“We need biosecurity efforts to be more impactful at the ground level. Not only to prevent major outbreaks, but to even protect employees and families from the things being taken home every day,” says Kirk Ramsey, Neogen’s professional services veterinarian who reviewed the biosecurity survey results.

Biosecurity Plans Lag Behind Threats

The survey reveals even among farms with established biosecurity strategies, commitment to reviewing and adapting these plans is lacking. While 68% of farmers with at least 250 dairy cows report having a biosecurity plan, 34% admit they do not review their plans regularly.

(Farm Journal)

On a positive note, 72% of dairy operators with 250-plus cows report they are currently making improvements to their biosecurity versus 58% of smaller dairy operators. Those producers are making improvements for a host of reasons, including recent on-farm or neighboring farm disease outbreaks, veterinarian recommendation and government or regulatory authority guidelines.

One respondent shares because their farm is a “closed herd” they’re not making any improvements to their biosecurity plan. All of this hints at a broader problem: Ongoing biosecurity practices might not be keeping pace with evolving threats.

Back to the Basics With Farm Security

The survey also uncovers significant gaps in fundamental farm security. More than 20% of surveyed dairies neglect to secure access to barns and animal housing. Monitoring or restricting visitor access is also a blind spot for 16% of producers, and only 33% of producers use camera surveillance to oversee their facilities. Additionally, 38% fail to control or limit access to areas where feed is stored or provided.

(Farm Journal)

Gaps in Hygiene and Herd Health

When it comes to farm hygiene and animal health practices, 72% of larger dairy operations have hand-washing stations included in their biosecurity protocol, and 75% use separate equipment for handling feed and manure. Even though more than half of respondents use technology, such as herd activity monitoring systems, to help identify sick animals, the overall picture suggests room for improvement in daily hygiene and health protocols.

(Farm Journal)

Training and Education Should Be Proactive

The approach to biosecurity training also calls for reform. The findings show a reactive pattern, with 32% of farms providing training only in response to biosecurity issues, while another 30% conduct quarterly meetings. These figures reveal substantial portions of the industry lack consistent, proactive staff education, an essential pillar of effective biosecurity management.

Chief Science Officer Jamie Jonker, Ph.D., with National Milk Producers Federation says biosecurity on dairy farms is a continuous process that requires proactive updates and employee education to keep pace with evolving disease threats.

“The National Dairy FARM Program offers comprehensive biosecurity materials and evaluation tools as well as certified FARM Biosecurity evaluators who can draft tailored plans and guide training to ensure consistent implementation,” he says. “Leveraging these resources helps producers stay ahead of risks and maintain a strong, resilient operation.”

(Farm Journal)

Cybersecurity: An Emerging Concern

Beyond biosecurity, the increasing reliance on technology introduces cybersecurity challenges. Only 29% of farmers have collaborated with cybersecurity experts to protect their farm systems and data. As farms grow more technologically interconnected, safeguarding digital infrastructure is an emerging need.

The insights from Farm Journal’s recent research paint a clear picture for the U.S. dairy industry: In an era of escalating disease threats such as H5N1 and NWS, a reactive or static approach to protection is no longer sufficient. Ultimately, this research serves as a pivotal reminder that biosecurity and cybersecurity are not one-time tasks, but dynamic, ongoing processes demanding continuous review and proactive management.

“Improvements in biosecurity will require a paradigm shift in how we see our individual operations’ vulnerabilities,” Ramsey says. “I believe there are some misconceptions around what biosecurity looks like. For many, it’s thought of as Tyvek suits and face masks, not clean boots and coveralls, and shower-in-shower-out facilities, not limited-farm entry. There are simple ways to create biosecurity plans into every operation, and there are experts in our industry building innovative solutions to the complexities of the cattle industry.”

Seeing the Whole Elephant: Systems Thinking and Animal Health

Mon, 24 Nov 2025 22:19:50 GMT

We all know the ancient parable of the blind men and the elephant: each man touches a different part of the elephant and becomes convinced he knows the whole animal. One feels the trunk and declares it a snake, another the leg and insists it’s a tree. Each observation is accurate, but each conclusion is deeply incomplete.

Veterinary medicine often falls into the same trap, not because of a lack of care but because of training to look closely. In a world where disease emerges from the interactions of nutrition, immunity, environment, behavior and management, the old parable reminds us the truth isn’t found in any single part. It’s found in the relationships between them.

Why Looking Closely Isn’t Enough

Pattern recognition is one of our greatest strengths. You learn to see classic presentations and link them with a diagnosis. For example, ketosis in a fresh cow or BRD in a calf with a cough.

But disease rarely lives in one organ system or one management practice. A narrow focus can deceive us. We might fixate on the ‘tusk’ because it looks sharp and obvious, while missing the constellation of forces actually driving the animal’s response.

Examples crop up everywhere:

A dairy lameness problem blamed solely on digital dermatitis, when the root cause is chronic wet bedding, poor ventilation and subtle changes in stocking density.
A calf barn respiratory outbreak attributed to infectious bovine rhinotracheitis, when the real sequence of events begins with colostrum quality, followed by fluctuating ventilation, then a weather front that pushes calves over the edge.
A feedlot dip in performance linked solely to a ration change, when heat stress, water access, bunk competition and handling stress created a cascade of interacting pressures.

Each diagnosis contains a piece of truth, but each is incomplete when treated in isolation.

Systems Thinking: Looking Between the Parts

Systems thinking is the discipline of understanding how elements interact to produce outcomes. It challenges us to stop asking what caused this and start asking how these factors combined to create this situation.

Dr. Brian Vander Ley of the University of Nebraska-Lincoln recently spoke on the topic.

“Systems thinking is actually a derivative of a field called ‘systems dynamics,’ which is a highly mathematical modeling field that’s used to predict the behavior of systems based on components in the system and relationships,” Vander Ley explains. However, systems thinking takes out the math component. “It’s a set of tools, processes and principles that enable us to focus on the relationship between parts of the system and not just some of the parts themselves.”

A system isn’t just a list of components. It is:

The feedback loops between nutrition and immunity
The way ventilation interacts with pathogen load
How handler behavior influences stress physiology
How management timing affects microbial dynamics
How one week’s decisions become the next month’s disease patterns

The iceberg analogy fits here too: What we see in the cow is only a small fraction of what’s really happening. The larger drivers of disease sit below the surface and remain invisible unless we deliberately go looking for them.

The heart of systems thinking is recognizing that diseases are rarely linear. They are networked. They emerge not from one factor but from several interacting simultaneously, sometimes amplifying, sometimes buffering each other.

In other words, the elephant is not just trunk + tusk + leg + ear. The elephant is the relationships that connect those parts into a living organism.

The Veterinarian as a Systems Navigator

Veterinarians already intuitively use systems thinking. You’re constantly piecing together physiology, environment and behavior. The challenge is doing it intentionally rather than incidentally.

This means asking broader questions:

Where did the system fail and why?
What feedback loops are reinforcing the problem?
Which variables are upstream versus downstream?
What invisible pressures are shaping what I can see?
What happens if one part of the system changes?

When we ask these questions, we stop thinking like the blind men — competing diagnoses based on isolated observations — and start thinking like systems analysts, integrating multiple perspectives into a coherent picture.

This is also dependent on communication within the animal care team.

“Communicating about it is really important, because we are really sure about our own experiences. When I go out and collect data with my own hands and my own eyes, I’m very confident in that data, and when I see information that’s very different, I tend to disregard that information,” Vander Ley says. “We want to engage in a kind of communication that allows us to appreciate that we’ve got different pieces of the elephant in hand.”

Having an open dialogue between owners, producers, veterinarians and academics allows for a broadened perspective for understanding what the problem is.

Case Example: Reframing a ‘Simple’ Mastitis Problem

Take a herd with climbing somatic cell count and increased clinical mastitis cases. A parts-focused approach might look at:

Teat-end condition
Milking protocols
Bedding
Culture results

A systems approach goes further:

How has cow flow changed through the parlor?
Are fresh cows being mixed too early?
Has ration moisture affected rumen health and lying time?
Are staff changes altering consistency in milking prep?
Has heat stress reduced rumination and immune resilience?
Are equipment cleaning routines changing due to workload?

Suddenly, the rising cell counts are no longer an udder health issue but a system problem — a signal, not a cause.

Stepping Back to See the Elephant

The parable of the blind men isn’t merely about limited perspectives; it’s about the illusion of certainty that comes from seeing only one piece of a larger, interconnected whole.

Veterinarians do some of their best work up close: palpating, listening to internal sounds, evaluating subtle signs. But the greatest diagnostic breakthroughs often come when we deliberately widen our view and consider not just the parts but the interplay between them.

Systems thinking doesn’t replace traditional diagnostic skills, it evaluates them. It turns isolated observations into meaningful patterns. It turns symptoms into stories. It turns disease into a map we can navigate instead of a puzzle we must solve.

In the end, seeing the ‘elephant’ means seeing not just the cow or the herd but the interconnected ecosystem that shapes every outcome.

Vesicular Stomatitis Outbreak in Arizona

Fri, 14 Nov 2025 16:34:09 GMT

USDA’s Animal and Plant Health Inspection Service has released a situation report on vesicular stomatitis virus (VSV) after the virus was identified on two Arizona farms this month.

While both reported cases were in horses, VSV also affects cattle, swine and other ruminants. The farms on which the virus was identified both also house cattle, though none have been found to be clinically affected.

In response to this outbreak, the Canadian Food Inspection Agency (CFIA) has announced temporary import restrictions on horses, ruminants and swine from the U.S. until further notice. The import of horses, swine and ruminants from VSV-affected states for all purposes is prohibited. Animals from other states that have been in a VSV-affected state at any point in the three weeks prior to import will be denied entry to Canada. Special accommodations have been made in collaboration with USDA regarding animal import for major Canadian livestock competitions and exhibitions.

What is Vesicular Stomatitis?

Vesicular stomatitis (VS) is a viral disease primarily spread by biting midges and flies, but can also be spread via animal-to-animal contact or exposure to saliva or fluid from ruptured vesicles. It is also important to protect yourself if working with infected animals as it is transmissible to humans causing an acute influenza-like illness.

VS is named for its characteristic vesicular lesions that form around the mouth, nose, udders and hooves. Along with these lesions, clinical signs of VS include:

excessive salivation (often accompanied by raised blisters on the lips, gums and tongue)
fever
feed withdrawal leading to weight loss

In cattle and horses, lesions around the hooves can lead to lameness, while teat lesions in dairy cattle can lead to mastitis and a severe drop in milk production. Affected swine usually first show signs of lameness caused by foot lesions.

Controlling Vesicular Stomatitis

While VS does not usually cause the death of an animal, it can lead to economic losses due to prevented animal movement and impacts on international trace. Farms with VSV positive animals must quarantine for 14 days after lesions appear on the last case at the location.

The last VS outbreak occurred from May 2023 through January 2024 affecting 319 locations across California, Nevada and Texas. VSV circulates annually between livestock and insect vectors in southern Mexico, only entering the U.S. when environmental factors support the northern movement of vectors.

If you suspect an animal might be infected with VSV, you should immediately contact local state and federal animal health authorities.

Monitoring Tools Can Strengthen Herd Health Programs

Wed, 12 Nov 2025 23:46:03 GMT

Early identification of health challenges is one of the most effective ways to reduce disease severity, minimize treatment costs and support long term herd productivity. While experienced caretakers have always relied on stockmanship and close observation, today’s operations can benefit from data beyond what we can consistently monitor with our own eyes. Monitoring tools provide an additional layer of insight, helping recognize subtle changes in behavior, intake or environment before clinical signs are obvious.

Dr. Tiago Tomazi, dairy technical services veterinarian with Merck Animal Health, shared his advice at the Dairy Cattle Reproductive Council annual meeting on how the dairy landscape has progressed, allowing us to use monitoring technologies and management practices for improved animal health.

“If we go back to the ‘80s, we can say that dairy farming was still dominated by small-and-medium-sized family farms, right? We used to call cows by name,” Tomazi says. “Then the ‘90s and 2000s came, and there was a marked acceleration in the growth of large scale operations. There was an explosion of studies, of investigations, and scientific investigation that helped a lot to bring us to the point we’re at nowadays as far as reproduction and production in dairy cows and cattle health.”

Following this growth in knowledge came the development of monitoring technologies to assist producers and veterinarians identify potential animal issues earlier.

That being said, data-driven decision making does not necessarily require advanced technology. In many herds, structured record keeping, routine scoring (such as body condition scoring, lameness scoring or feed bunk assessments), and consistent visual checks are foundational monitoring practices. The goal is to identify patterns and changes over time, not just isolated events.

Combine Technology with Strong Management Practices

When technology is added on top of strong stockmanship, the combination can be especially powerful.

“Point No. 1 is that monitoring systems are not a diagnostic tool,” Tomazi reminds. “But they help in identifying a cow that’s not having a good day.”

These activity monitoring technologies are not meant to tell you what ailment the cow has, but rather to alert you that a cow may be worth checking up on.

“Biology is not math,” Tomazi says. “While math uses formulas, numbers and calculations to get you the exact result, biology [has to] take into consideration a set of factors associated with the biology of the cow and the environment.”

While a variety of wearable tools exist for the earlier recognition of health changes, the interpretation of the data remains critical. Similar patterns can have multiple causes. For example, a decrease in rumination may reflect heat stress, early illness, social stress or rumen upset. Likewise, changes in activity could indicate estrus, discomfort or pain. Connecting these data points to clinical reasoning and management is key.

Application Evidence from Research

Data from these monitoring tools can be applied for health predictions in a number of scenarios.

Chabel and colleagues from the University of Florida evaluated of over 4,500 dairy cattle across three commercial dairy herds wearing automated monitoring devices designed for estrous detection. They found early postpartum estrous characteristics were valuable indicators of reproductive potential; they were able to identify cows at risk for suboptimal fertility. By combining these characteristics with other health, genetic and environmental data, they were able to improve the prediction of fertility outcomes and provide targeted reproductive management for the cattle.

A series of three studies by Stangaferro and colleagues at Cornell University investigated the use of automated monitoring devices for the identification of health issues in dairy cattle. They found health index scores (calculated using an algorithm using rumination and activity data) provided sensitive detection for cattle with metabolic and digestive disorders , reducing time to clinical diagnosis by approximately 2 days. However, this system was less sensitive for the detection of mastitis and metritis , being most effective for cattle with severe cases.

While these monitoring devices may not perfectly identify all health issues in your herd, they can certainly help identify some disease signs earlier than human observation alone. It’s also important to note that the implementation of these monitoring devices will be different from farm to farm.

“We have to take into consideration the level of disease protection you want at your farm as well as the feasibility and labor capabilities,” Tomazi says. “You can be very intensive, but if you don’t have the people to provide you with that intensity, then it makes everything harder. On the other hand, you can be less intensive and find that balance where you’re not going to compromise the reproduction or production during the location of those cows.”

Data Interpretation is just as Important

Training caretakers to recognize when and how to respond to monitoring data is just as important as selecting the technology. A monitoring system is only as good as the team interpreting it.

While the benefits can be significant, monitoring tools also introduce challenges. The amount of data generated can be overwhelming. Time and training is required to get the most out of your investment and use the data effectively. This provides a great opportunity for veterinarians and producers to work together in prioritizing the metrics that are the most actionable and will make the most impact on the operation’s herd health goals.

The Future with Monitoring Tools

Looking ahead, predictive models and machine learning based alerts are likely to play an increasing role in herd health programs. With these systems will come the need for increased expertise on interpretation, contextual decision making and ongoing evaluation of how monitoring tools fit into preventative care strategies.

“I think integration is what we are walking toward,” Tomazi says. “The integration of these technologies with biological factors and management factors all together will help us make decisions considering the specific scenario at each dairy farm.”

Ultimately, monitoring tools are most effective when combined with strong stockmanship and veterinary oversight. When data and observation inform each other, disease can be detected earlier, interventions become more targeted and herds can become healthier overall.

5 Tips for Vaccine Handling

Fri, 07 Nov 2025 16:53:40 GMT

Vaccines are one of the most effective and economical tools available to maintain herd health, reduce disease loss and support animal well-being. However, even the best vaccine can fail if it’s not handled correctly. Dr. Jon Townsend, dairy technical services veterinarian with Merck Animal Health, recently touched on the topic during a Dairy Calf and Heifer Association webinar .

“You’ve made the investment in those vaccines. You want to get the best response out of them. You want to get the best cow health possible,” Townsend says.

Whether you’re working with calves, replacement heifers or mature cattle, following consistent vaccine handling practices ensures your investment delivers the intended immunity. Here are five key guidelines to keep in mind.

1. Store Vaccines at the Right Temperature

Vaccines are sensitive, biological products. Many must be kept refrigerated at a specific temperature range to remain effective.

Use a dedicated refrigerator (not the one used for drinks and lunches), as frequent door opening causes temperature swings.
Place a thermometer in the fridge to monitor temperature regularly.
Avoid storing vaccines in the refrigerator door where temperatures fluctuate the most.

2. Don’t Mix all your Vaccine at Once

Many livestock vaccines are sold as two-part products. Once mixed, the live organisms begin to break down.

“Only mix what you’ll use in the next one to two hours if you have to mix up a vaccine,” Townsend advises. “Your modified live vaccines you have to mix. So don’t mix a huge bottle that’s going to take the whole day to use. By the time you get to the last dose that vaccine has potentially degraded, and you won’t get the same response that you would have immediately after reconstitution.”

3. Keep Mixed Vaccines Cool and Out of Sunlight

Heat and sunlight can rapidly damage vaccines, particularly modified-live vaccines.

Keep syringes and mixed bottles in an insulated cooler with cold packs.
Do not place vaccine bottles on the chute, in your shirt pocket, or on a truck dashboard.
Check your cooler throughout the day to ensure cold packs are still cold and not melted.

Unsure about what cooler to use? Consider making it yourself.

“You can either buy a fancy one, or you can make one yourself with an Igloo cooler and drill some holes,” Townsend says. In the end, the goal is the same. “It’s really important to keep that vaccine cool. If you’re using a multi-dose syringe, make sure you’re keeping [it] cool between calves.”

4. Maintain Needle Cleanliness

Contamination can destroy vaccine potency and introduce infection to animals.

Use new clean needles when drawing vaccine from the bottle.
Do not set uncapped syringes or needles down on surfaces like tailgates or barn rails.
If a needle becomes dirty, bent or touches anything questionable, replace it.

“We need to be thinking about changing out needles more frequently than [we] did 30 years ago,” Townsend says. “Then disinfect the needle and syringes after use or dispose of them, and think about disinfecting multi-dose syringes.”

Townsend also highlights the importance of making sure there is no disinfectant residue remaining after cleaning as it has the potential to inactivate your vaccines. Producers and veterinarians should work together to set up protocols for syringe reuse.

5. Use Sharp, Appropriate Needles

A sharp needle ensures a clean injection and reduces animal discomfort.

Replace needles regularly and check for sharpness.
Choose needle size based on animal size, vaccine viscosity and route of administration:
- Subcutaneous: typically 16 to 18 gauge, ½" to ¾"
- Intramuscular: typically 16 to 20 gauge, 1" to 1½"

Townsend specifically warns about the development of burrs, small barbs or defects that can catch on skin, on your needles after too many uses.

“If you wouldn’t want it going into your arm for a vaccine, you shouldn’t be putting it into a cow or calf either,” he says.

Overall, the immunity an animal gains from vaccination is only as good as the care taken in handling the product. Proper storage, careful mixing, maintaining temperature and using clean, sharp needles are straightforward steps that protect your investment and your herd.

Veterinarian Becomes Disease Detective: Nichols Connects Animal Disease and Human Health

Tue, 07 Oct 2025 20:00:14 GMT

Growing up on a New Mexico ranch, veterinarian and public health leader Megin Nichols says she learned early the health of animals, humans and the environment are deeply connected.

Initially planning to practice small animal medicine, she says her plans began to pivot when she met a Centers for Disease Control and Prevention (CDC) epidemic intelligence service officer who sparked her interest in public health. That realization led her to pursue a master’s degree in public health at the University of Minnesota, with a focus on food safety and biosecurity. Her career has included roles in local, state and federal health departments, investigating foodborne illness outbreaks and developing strategies to prevent them.

“Life has a way of taking you in places you never anticipated,” she shared during the 2025 Henry C. Gardiner Global Food Systems Lecture Oct. 6 at Kansas State University.

Today, as the CDC’s director in the division of foodborne, waterborne and environmental diseases, she lends her expertise to efforts involving disease investigation, food safety, antimicrobial resistance and agriculture literacy.

Megin Nichols has more than 15 years of zoonotic disease experience and has served at the federal and state levels. She has served as the lead of the Enteric Zoonoses Team investigating multistate outbreaks of Salmonella and E. coli. Prior to joining CDC, Nichols worked as the Principal Investigator of the Active Bacterial Core Surveillance Program at the New Mexico Department of Health for five years.

(Angie Stump Denton)

One Health: Connecting Animal Disease and Human Health

Nichols’ work focuses on the One Health concept.

“One Health is recognizing the health and well-being of humans, of animals and our environment are all interconnected,” she explains. “One Health is something that many of us do every single day and are very, very aware of, especially if you have ties to agriculture and the land. But One Health as a concept oftentimes is difficult to fully understand.”

Nichols says One Health is:

Ongoing relationships with animal agencies.
Understand the culture of agriculture.
Having access to integrated human and animal surveillance.
Protocols for conducting joint response investigations.
Agreements for sharing biological samples and lab results.
Established lines of communication with agriculture and animal industry.
Plans for unified communication messaging.
Need to build linkages and trust before and outbreak.

“What happens in one area can significantly impact others — whether it’s a wildfire, a disease outbreak or environmental changes,” Nichols summarizes.

Pandemic and Disease Response Insights

Nichols was a leader in investigating and finding unique solutions for the livestock industry and specifically meat packing industry related to COVID-19.

“In April 2020, I got a call from my supervisor saying there are some meat, poultry packing plants that are going down because of labor shortages and illness,” she explains.

She selected and lead a team to figure out how to get the plants opened back up safely and to find unique solution to deal with the related animal welfare issues.

Summarizing the experiences, Nichols reports the estimated economic cost of COVID-19 is $14 trillion. Along with supply chain disruptions the industry experienced changes in consumer behavior, labor shortage and complex operations challenges. On a positive note, she says the industry did experience a lot of innovation and uptake of technology due to the pandemic, which resulted in innovative approaches to workplace safety and communication.

“We saw innovative strategies where if one person got sick, they looked around that worker and said, ‘OK, who do we need to monitor quickly for symptoms?’” she says.

Nichols also discussed the increase in salmonella outbreaks during the pandemic. She links the rise to the increase in backyard poultry ownership and the improper handling of backyard chickens.

“Many new chicken owners were unaware of disease transmission risks,” she explains.

Nichols also shared insights to H5N1 influenza and emphasized the complexity of tracking and preventing. She highlights the need for integrated, cross-species surveillance and communication strategies.

She also touched on emerging threats, including New World screwworm (NWS) . Her message emphasized the importance of prevention, control and preparedness.

She shares these five key strategies related to NWS:

Surveillance. Early dection through wound inspections and reporting in livestock.
Sterile Insect Technique (SIT). Ongoing release of serile male flies to prevent reproduction.
Biosecurity. Movement control of imported animals and monitoring at entry points.
Public Awareness. Education for doctors, ranchers, veterinarians and travelers.
Rapid Response Planning. Multi-agency coordination to contain outbreaks swiftly and deploy sterile flies.

Agricultural Literacy, Communication is Key

“Growing up in the middle of nowhere, I also came to understand that not everyone appreciates — or even understands — where their food comes from,” Nichols says.

She shared a 1993 study that revealed significant gaps in public knowledge about agriculture. She summarizes understanding food systems involves knowing:

Where food comes from.
How it’s produced.
Its impact on economy, environment and technology.

Throughout her lecture she shared the importance of transforming complex scientific concepts into engaging, accessible insights that resonate with students, farmers, ranchers and public health professionals alike.

“It doesn’t matter how much information we have if we don’t get it out to the people,” Nichols says.

She stresses the importance of agricultural communication specialists in translating scientific information and engaging audiences.

“Don’t leave the communications to the scientists,” she says.

Nichols emphasizes that agricultural literacy and effective communication are crucial for bridging knowledge gaps and building public understanding of food systems.

She shares this advice for agricultural advocates:

Bring agricultural perspective to discussions by speaking up and sharing lived experiences.
Challenge misconceptions with personal stories by focusing on storytelling rather than technical details.
Understand your audience and use relatable language and provide context.

Nichols stresses the importance of preparedness and collaboration. She explains the importance of local-level discussions and community preparedness, suggesting that some of the most effective emergency preparedness conversations happen “at the coffee house” or during casual community gatherings.

Share Your Thoughts: APHIS To Host Animal Health Listening Sessions

Fri, 03 Oct 2025 11:46:05 GMT

POSTPONED: The Farm Bill Animal Health Program Listening Sessions that were scheduled for October 6, 7 and 8 have been postponed.

The U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) is advancing animal disease preparedness and response through its Farm Bill animal health programs. Beginning in fiscal year 2026, funding for these programs will increase to $233 million annually under President Trump’s One Big Beautiful Bill .

This includes:

$153 million per year for the National Animal Vaccine and Veterinary Countermeasures Bank ( NAVVCB )
$70 million per year for the National Animal Disease Preparedness and Response Program ( NADPRP )
$10 million per year for the National Animal Health Laboratory Network ( NAHLN )

APHIS will host three virtual listening sessions to gather stakeholder input on how these new funds should be used to strengthen national, regional, and local capabilities to prevent, prepare for, and respond to animal disease outbreaks. APHIS will use the feedback to inform future program planning.

Each session will focus on one of the three programs. While advance registration is not required, we encourage participants to submit their name and affiliation to help us plan and facilitate the sessions.

Listening Session Schedule

Monday, Oct. 6 | 2 to 3 p.m. ET
Topic: National Animal Health Laboratory Network (NAHLN)
Join the Listening Session on Teams or
Call-In: 202-650-0123; Phone Conference ID: 697 205 668#
Tuesday, Oct. 7 | 2 to 3 p.m. ET
Topic: National Animal Vaccine and Veterinary Countermeasures Bank (NAVVCB)
Join the Listening Session on Teams or
Call-in: 202-650-0123; Phone Conference ID: 440 983 713#
Wednesday, Oct. 8 | 2 to 3 p.m. ET
Topic: National Animal Disease Preparedness and Response Program (NADPRP)
Join the Listening Session on Teams or
Call-In: 202-650-0123; Phone Conference ID: 188 744 006#

To ensure as many participants as possible can speak, we ask that speakers limit their comments to 90 seconds or less.

Stakeholders are also invited to submit written comments before or after the events using the Farm Bill Funding Stakeholder Feedback Form . Written comments will be accepted through Oct. 15, 2025.

This is a valuable opportunity for all interested stakeholders to help shape the future of these critical animal health programs.

Harness the Full Potential of Your BRD Vaccine with the Right Adjuvant

Mon, 29 Sep 2025 13:24:54 GMT

Bovine respiratory disease (BRD) is one of the greatest threats to young calves, and gaining protection through vaccines isn’t always straightforward. Maternal antibodies, passed through colostrum, can block some vaccines from boosting immunity. The key to overcoming that hurdle? Choosing a vaccine with the right adjuvant.

Maternal Antibodies Can Interfere with Vaccines

“Years ago, vaccine response was so variable in young calves,” says Curt Vlietstra, DVM, Boehringer Ingelheim. “At the time, we didn’t know if their immune system simply wasn’t ready, or if there was a problem with the vaccines. With the research we have now, we understand that the majority of interference comes from maternal antibodies that are still present in the calf at the time of vaccination.”

Passed down from the cow via colostrum, maternal antibodies are not only a calf’s first line of defense against disease, but they also have the tendency to neutralize vaccines.

Those maternal antibodies naturally wane when the calf is between 2 and 6 months of age. As this maternal immunity dwindles, vaccination becomes critical in boosting and building calf immunity. The largest challenge in bridging these two forms of immunity is timing. Chris Chase, DVM, Professor, Department of Veterinary and Biomedical Sciences, South Dakota State University, says finding a vaccine with the right adjuvant can eliminate this guessing game.

Adjuvants Are Critical to Capturing Immunity in Young Calves

Adjuvants — although often overlooked — can determine whether a calf successfully develops a robust, lasting immune response, or remains vulnerable to BRD pressure. They work by drawing immune cells to the injection site, and helping the calf’s body recognize and remember the vaccine. Some adjuvants also slow the release of the vaccine, giving the immune system more time to respond.

“With the types of adjuvants we have now, we can get strong, long-lasting immune responses, even in calves with maternal antibodies,” Chase shares. “Although, just because a vaccine label says ‘adjuvanted’ doesn’t mean it offers the protection we need. It’s important that we ask what kind of adjuvant it is and what it’s proven to do.”

Over the last few decades, peer-reviewed studies and fieldwork have shown that Pyramid ^® vaccines can succeed, even in the face of maternal immunity, thanks to its unique adjuvant, Metasim^®. Specifically designed to address the challenges of early calfhood vaccination, the dual-phase technology of the Metasim adjuvant can stimulate a balanced, robust immune response in calves as young as 30 days of age.

(Boehringer Ingelheim)

“Historically, it was accepted as fact that maternal antibodies would block the injectable vaccine,” Vlietstra says. “Now we know Metasim works alongside the preexisting antibodies, not against them.”

Systemic Immunity Builds Long-Lasting Protection

Another key factor in vaccine selection is delivery method. For a time, intranasal vaccines were thought to be the only effective option to protect young calves against BRD. While intranasal vaccines can offer local immunity for calves at risk of BRD exposure soon after birth, some may miss the opportunity to stimulate robust, systemic immunity.

While local immunity helps block infection right where it starts (which is usually in the respiratory tract with BRD), systemic immunity is what builds broad, long-lasting protection, by training the calf’s entire immune system to respond.

When calves encounter BRD pathogens weeks or even months after vaccination, a strong systemic immune response helps them recognize and fight off infection more effectively, reducing severity of disease and its long-term impact on health and performance.

“In some ways, we’ve become very reliant on intranasals,” Vlietstra notes . “I’ve seen protocols that say, ‘This calf may not respond to an injectable, so let’s give another intranasal.’ That choice ends up potentially delaying systemic protection.”

Injectable vaccines with the right adjuvant have been proven to stimulate both local immunity in the respiratory tract, and systemic immunity that circulates in the bloodstream.

Even the Best Vaccine Needs Correct Timing and Care

“There are plenty of producers and veterinarians who have firsthand experience of vaccines not working,” Vlietstra says. “If we’re not seeing results, it’s time to evaluate how we’re using the product and when.”

It’s common to schedule vaccination alongside other times calves are being worked, like weaning or transportation. While this may save labor and time up front, vaccinating calves during other stressful events can limit immune response.

“If cattle have had a long truck ride, ideally, we’d let them unload and rest for 24 to 48 hours before we vaccinate,” Chase explains. “I know not all operations have the resources to do this due to labor constraints, but water and rest time after a stressful event will set cattle up for a better immune response.”

To get the most of any vaccination program, good animal handling, husbandry and biosecurity protocols play a role in preventing and controlling BRD. By staying on top of health management and using products according to label, vaccines are more likely to capture desired results.

“The world’s best vaccine is not going to overcome overwhelming challenges,” Chase stresses.

The needs of every herd are different. Working closely with a veterinarian is key to finding success tailored to your cattle and operation.

U.S.-Mexico Border Battle Continues As the Threat of New World Screwworm Intensifies

Wed, 24 Sep 2025 20:04:06 GMT

With New World screwworm (NWS) confirmed just 70 miles from the U.S. border , producers, government officials and industry leaders are taking action. Finding NWS along one of the most heavily trafficked commercial thoroughfares in the world from Monterrey, Nuevo Leon, to Laredo, Texas, is a red flag for the industry. Emphasizing the importance of maintaining strong safeguards, it’s time to plan for not “if but when” NWS crosses the border.

On Monday, Secretary of Agriculture Brooke Rollins confirmed protecting the U.S. from NWS is non-negotiable and a top priority for President Trump.

UPDATE ON SCREWWORM THREAT:

Protecting the United States from New World Screwworm is non-negotiable and a top priority for @POTUS.@USDA landed boots on the ground this morning in Nuevo Leon, physically inspecting traps and dispersing sterile flies after the detection of the…
— Secretary Brooke Rollins (@SecRollins) September 23, 2025

“The southern border remains closed to livestock trade, and we are aggressively expanding trapping and surveillance,” she wrote. “At the same time, we’re expediting operations at our sterile fly dispersal facility at Moore Air Base in Texas .”

On Tuesday, Secretary of Agriculture Brooke Rollins reported 80,000 sterile flies were released on “spot” and nearly 200 surge staff had been deployed to Mexico.

Thank you, @IngrahamAngle, for paying attention to this important issue. Due to multiple failures from our southern neighbors and failure to act in the last Admin, the devastating parasite New World Screwworm is knocking on our southern borders door. We’re not waiting, we’re… pic.twitter.com/ZO5Vx5oes8
— Secretary Brooke Rollins (@SecRollins) September 24, 2025

Mexico’s Response To New World Screwworm

According to Reuters, Mexican’s agriculture ministry said there is no risk of adult screwworm fly emergence due to the early detection of the infected bovine, which was confirmed on Sept. 21. The infected animal was in a shipment of 100 animals originating from the Gulf Coast state of Veracruz, according to the statement.

Fly traps in northern Mexico have not detected a single screwworm fly.

U.S.-Mexico Border Remains Closed to Cattle Trade

The Mexican border closure remains a topic of debate. The September Ag Economists’ Monthly Monitor found 80% of ag economists surveyed oppose reopening the border to Mexican cattle due to screwworm risks.

(Farm Journal)

The border closure has created significant division within the cattle industry with producers, feeders and industry leaders on both sides of the fence.

“We have some cattle people that are glad it’s closed. We’ve got others who are hit pretty hard and are not happy about it,” explains David Anderson, Texas A&M professor and extension specialist — livestock and food product marketing.

NWS is a threat the industry can not ignore, says the ag economist with more than 30 years under his belt.

“I think this is the most serious problem the industry has faced since I’ve been a livestock economist,” he stresses.

From his perspective, keeping the border open with heightened monitoring and surveillance could have potentially been more effective than implementing a total closure.

“If we go back and look at data from the early ‘70s, when we had a big screwworm outbreak in the U.S. and Mexico, the border was open,” he says. “I probably would have leaned to not closing the border to begin with. I understand why you would want to do that, but I don’t know that it’s ended up reducing the likelihood that we’re going to get screwworms, and yet we’re paying a price for that.”

According to Anderson the economic consequences to the border being closed are:

Significant loss of approximately 26,000 imported cattle weekly
Estimated 18% reduction in cattle placements in Southern plains
Contributed to tighter beef supplies and higher consumer prices
Substantial economic hit to cattle feeders and ranchers

At this point, he’s quick to admit keeping the border closed is the best option.

When it comes to reopening the border, Derrell Peel, Extension livestock marketing specialist with Oklahoma State University, suggests the decision is not straightforward.

“Given everything I’ve experienced, it’s probably prudent to leave the border closed,” he says.

He adds any reopening should be “under very, very controlled, limited circumstances.”

Peel emphasizes the need for a collaborative approach with Mexico.

“We’re kind of in it together, and so whether it’s here or there, we’ve got to work together,” he summarizes. “We’re going to need to control it in both places. Otherwise, it’s not going to benefit either one of us.”

He also points out not everybody in Mexico is sorry the border is closed. For example, cattle buyers in Mexico can source cattle cheaper because the border is closed.

“Keeping the border closed does affect the movement of cattle south of the border ... it builds a backstop for cattle movement north,” he adds.

Peel notes cattle from Central America to Panama have increasingly made their way to the Mexican market, which validates NWS movement in Mexico and why recent confirmation has occurred.

“The longer this goes on, the more the Mexican industry will adjust,” he says. “It might permanently change the way the [U.S. and Mexico] work together.”

Texas Rancher Weighs In On Impact of New World Screwworm

Texas rancher Wayne Cockrell says the parasite’s entry into the U.S. is inevitable, suggesting that winter and colder weather might temporarily delay the spread until next April or May. Cockrell, who serves as the Southwestern Cattle Raisers Association director and chair of the cattle health and well-being policy committee, recently joined AgriTalk to talk about NWS.

“We would much rather stop this on Mexico’s southern border than our Southern border,” Cockrell says.

Mexican feeder cattle traditionally represented 30% of Texas feedyard inventory, he adds, but with current restrictions, feedlots are adapting.

“I think a lot of those feedyards have moved to the dairy-cross side,” he adds. “They have had to change the way they do business.”

Noting the broader economic implications of the border closure, 1.2 million fewer cattle for Texas represents “about two weeks” of impact nationwide, according to Cockrell.

“Winter and sterile flies is what we need now,” Cockrell summarizes.

Your Next Read: The Smell You’ll Never Forget: A Calf Infested with New World Screwworm

Emergency Use of Animal Drugs Approved to Combat New World Screwworm

Tue, 19 Aug 2025 16:09:22 GMT

The U.S. Department of Health and Human Services (HHS) issued a declaration on Aug. 19 allowing the U.S. Food and Drug Administration (FDA) to issue Emergency Use Authorizations (EUAs) for animal drugs to treat or prevent infestations caused by the New World screwworm (NWS).

This declaration applies only to drugs for animals. NWS infests warm-blooded animals, including livestock, pets, wildlife, and, in rare cases, humans, causing severe tissue damage and sometimes death. The risk to human health in the U.S. remains very low, but the potential future threat to animal populations and the food supply chain requires proactive action.

Although eradicated from North America and Central America decades ago, NWS has progressed north since 2022 and is now approaching the U.S. border with Mexico. This parasite poses an emerging threat to livestock and food security, with potential impacts on both national security and animal health.

“Today we are taking decisive action to safeguard the nation’s food supply from this emerging threat,” says HHS Secretary Robert F. Kennedy, Jr. “This authorization equips FDA to act quickly, limit the spread of New World Screwworm, and protect America’s livestock.”

Currently, there are no FDA-approved drugs for NWS in the U.S. The FDA through an EUA can authorize the flexible, faster use of certain animal drug products that may be approved for other purposes, or available in other countries, but not formally approved for NWS in the U.S. This ensures veterinarians, farmers, and animal health officials have timely access to the tools they need to protect pets, livestock and the nation’s food supply.

“Thank you to my friends and partners Secretary Kennedy and Commissioner Makary who are answering the call and supporting our aggressive plan to push back and ultimately defeat this devastating pest. This emergency use authorization is another tool we can use in the fight against New World Screwworm,” says Secretary of Agriculture Brooke L. Rollins. “Our cattle ranchers and livestock producers are relying on the Trump Administration to defend their livelihoods. Stopping this pest is a national security priority and we are linking arms across President Trump’s cabinet to defend our borders and push back this threat.”

FDA Commissioner Marty Makary, M.D., M.P.H., adds, “Our priority is to safeguard both animal health and the nation’s food supply. FDA is acting swiftly and responsibly to help ensure we have the necessary tools to prevent and control New World Screwworm, minimizing risks to agriculture and public health.”

FDA will provide future guidance to veterinarians and stakeholders on the appropriate use of any products authorized for emergency use and update the New World Screwworm: Information for Veterinarians page.

Not All Milk Fever is the Same

Tue, 29 Jul 2025 18:10:19 GMT

For dairy farmers and nutritionists alike, keeping fresh cows on their feet and healthy becomes a priority the moment they enter the dry-cow pen. This includes working to stay ahead of hypocalcemia, also known as milk fever.

On a recent episode of the “Dairy Nutrition Black Belt” podcast, Laura Hernandez, professor of lactation physiology at the University of Wisconsin-Madison, shares her perspective on calcium metabolism, prevention strategies and why a slight drop in calcium might not always be a bad thing.

Types of Hypocalcemia
Although hypocalcemia is often discussed as a single issue, Hernandez emphasizes that it presents in different forms, each with unique timing, symptoms and consequences for cow health and productivity.

1. Classic Hypocalcemia
This is the textbook case most producers are familiar with. It typically occurs within the first 24 hours postpartum and may present as clinical milk fever or more subtly as subclinical hypocalcemia. Cows often appear weak, with muscle tremors, cold ears and difficulty standing.

2. Delayed Hypocalcemia
In this less recognized form, cows appear normal for the first two days postpartum with adequate blood calcium levels. The drop doesn’t come until day four or later, at which point cows may experience clinical or subclinical symptoms.

“Delayed hypocalcemia is sneaky,” Hernandez says. “You might think a cow is in the clear, only to have her crash a few days later.”

Identifying delayed hypocalcemia often requires proactive monitoring of blood calcium levels beyond the immediate post-calving period. Herds may benefit from targeted sampling or observation of early warning signs like reduced feed intake or lower activity levels.

3. Persistent Hypocalcemia
This form involves cows that start with low calcium levels on day one or two and fail to recover by day four. These animals are particularly at risk.

“These cows likely will have more diseases like displaced abomasums, retained placentas and ketosis,” Hernandez notes. “They’ll also have collectively lower milk production over the course of their lactation and are more likely to leave the herd.”

Persistent cases are often tied to underlying issues with calcium mobilization and metabolic health. Identifying them may require a combination of bloodwork and tracking clinical outcomes across early lactation.

4. Transient Hypocalcemia
According to Hernandez, one of the more surprising developments in hypocalcemia research is the discovery of a form that may actually benefit cows: transient hypocalcemia.

This short-term drop in blood calcium occurs within the first 24 to 48 hours postpartum but resolves on its own by day four. Research from Dr. Jessica McArt’s lab at Cornell suggests cows in this category often outperform their peers.

“What she’s found in her production data is that indeed these cows make more milk, they have less disease and they often make more milk than the cows that are never subclinical,” Hernandez says.

She hypothesizes transient cows are more efficient at activating key hormones that regulate calcium absorption and mobilization, allowing them to adapt quickly to the demands of early lactation.

“Calcium status is a hormone-driven process,” she adds. “If we do too much to keep calcium up, sometimes the cow can’t reset herself and have that trigger of negative feedback so she can mobilize or absorb more calcium.”

Using Nutrition as Prevention
As with many transition cow issues, prevention remains the best strategy. But Hernandez cautions against a one-size-fits-all mindset.

“Farms do this very differently, and it’s not a one-size-fits-all approach,” she says. “You have to take into consideration management strategies, what you can get your workers to do and what the cost-benefit ratios are.”

Several nutritional tools are available to help reduce the risk of hypocalcemia:

Low potassium diets: Often used in dry cow rations to promote calcium mobilization.
Calcium binders: These products can help prevent calcium absorption during the prepartum period, which can prime the body for efficient mobilization postpartum.
Phosphorus binders: Hernandez notes this is an emerging area of interest, especially as phosphorus metabolism receives renewed attention. She notes high dietary phosphorus can interfere with calcium absorption and regulation, especially during the transition period.

“Phosphorus has kind of been the forgotten mineral,” she adds. “But it’s coming back into the conversation, not just from a nutrition standpoint, but also for manure management and sustainability.”

Phosphorus binders may offer a tool to fine-tune the balance and support better overall mineral management — but more research is needed to determine how and when to use them most effectively.
DCAD (Dietary Cation-Anion Difference) diets: One of the most widely used approaches, DCAD diets create a mild metabolic acidosis prepartum to increase calcium mobilization from bone and absorption in the gut.

DCAD remains a cornerstone strategy when well managed.

“It works extremely well but does have some management input that needs to happen in order to keep it working,” Hernandez adds.

In a recent study, her team compared different dietary strategies, including a calcium-binding product that actually functioned more like a phosphorus binder. While the sample size — 40 cows per treatment — was too small for definitive conclusions, it highlighted the complexity of mineral interactions and the need for ongoing evaluation.

“Not all these dietary strategies are equal in what they do, and we really should make a good attempt to understand that,” she says.

Looking Ahead
Although hypocalcemia has been studied for decades, Hernandez stresses the need for continued research, particularly to better support cows with transient hypocalcemia and to prevent the delayed and persistent forms that contribute to long-term health issues and reduced milk production.

“We would really have to do a larger study to get at: What’s the true production response? What is the true health response?” she says. “But the goal would be to keep cows in the herd longer and also to keep them healthier and producing at a maximal level.”

Hernandez also highlights a growing interest in phosphorus — a mineral that has received relatively little attention in recent years.

“Phosphorus is like a lost mineral from what I could tell in the literature,” she adds. “No one’s been really doing much with that until recently, and so I think there’s some opportunity to understand that as well — especially from a manure and nutrient management standpoint.”

As Hernandez notes, milk fever can present itself in many different ways and at different times. That’s why it’s important to work closely with your nutritionist and veterinarian to develop a plan that fits your herd. Whether it’s fine-tuning dry cow diets, monitoring calcium levels after calving or adjusting treatments based on cow response, a team approach can help catch issues early and keep fresh cows off to a strong start.

Protect the Herd: The Signs to Watch for Calf Pneumonia

Wed, 09 Jul 2025 11:44:05 GMT

Pneumonia in young calves is an important contributor to death loss before weaning. Many veterinarians and cattle producers think of post-weaning respiratory disease, also known as Bovine Respiratory Disease (BRD), when they think about pneumonia in cattle; but calves can get pneumonia while they are still suckling their dams.

Bob Larson, K-State veterinarian, says because the risk factors associated with pre-weaning respiratory disease differ from BRD in stocker and feedlot cattle, which is usually associated with commingling and transportation.

“Our understanding of how to prevent and control BRD in post-weaned calves is not sufficient to address pneumonia in suckling calves,” he says. “Several studies investigating calf pneumonia have reported that an average of 3% to 11% of calves are expected to suffer from the disease each year. In addition, nearly 1.5% of calves will die from pneumonia before they reach the age of weaning; which makes it the second leading cause of pre-weaning death with only scours causing more losses.”

The most likely age for calves to be diagnosed with pneumonia is between 70 and 150 days of age.

Larson says cases of pneumonia are most likely to appear in:

Herds that have more cases of calf scours.
Herds that bring in nursing calves from outside herds to graft onto cows that lost their calves.
Creep-fed calves.
Herds that synchronize cows.

“Calves born after a difficult birth and calves that failed to consume enough colostrum have been shown to be at higher risk of getting sick and dying before reaching weaning age,” Larson explains.

Veterinarians indicated in a survey that weather, calving in confinement, failing to adequately vaccinate the herd, and nutritional deficiencies were also suspected for contributing to the risk of calf pneumonia.

Signs of Pneumonia

“Many times, the first sign that a herd has a problem is when a calf is found dead,” Larson warns. “Because death in young calves can also be caused by other diseases such as blackleg, digestive tract disease, or trauma, a veterinarian will probably need to examine the dead calf and may need to submit samples to a diagnostic laboratory to identify the cause of death.”

If you find calves that show signs of pneumonia such as rapid breathing, laying down and being reluctant to rise, and having a high temperature should be treated with an appropriate antibiotic after consulting with your veterinarian.

Tips for Prevention

Larson says vaccinating calves against viruses such as bovine viral diarrhea (BVD), infectious bovine rhinotracheitis (IBR), bovine respiratory syncytial virus (BRSV), and bacteria such as Mannheimia haemolytica and Pasteurella multocida may help prevent outbreaks of calf pneumonia or reduce the severity of disease, but we know that a young calf’s immune system is not able to respond as well to vaccinations as an older calf’s.

“Because even a calf with a good immune response can be overwhelmed by a large exposure to germs, a successful plan to prevent disease in young calves needs to involve more than just vaccinations,” Larson adds.

He says the herds that have the best calf health have a short calving season and few heifers and cows experiencing calving difficulty. In addition, try to keep young calves away from mud and other calves as much as possible.

“Cows that calve in good body condition and that are on a good plane of nutrition are more likely to have healthy calves,” Larson says. “The best disease-control strategy is to focus on having good overall health of the cows and calves by meeting the herd’s nutritional needs, providing a good environment and timely use of vaccinations in the cows and calves.”

In summary Larson says, if calves are affected with pneumonia while suckling their dams on summer range, you should be prepared to recognize and treat cases as early as possible with appropriate antibiotics in order to minimize death losses.

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7 Management Practices for BRD Mitigation

Wed, 11 Jun 2025 13:44:10 GMT

The threat of disease-causing bacteria, Mycoplasma bovis, has risen with the increase of comingling in confinement cow-calf operations, according to Vickie Cooper, DVM, a Zoetis beef technical services from Iowa.

M. bovis causes bovine respiratory disease (BRD), targeting beef calves, and leads to irreversible lung damage, mortality, and higher production costs, she adds.

The bacteria are present in the respiratory system of perfectly normal calves but become a bigger problem when calves face stressors such as transportation, commingling, entry into the feedlot, and weather changes, Cooper explains.

Although disease symptoms are similar, the nature of M. bovis makes this pathogen more challenging to detect and treat than other BRD-causing pathogens, she adds.

“Mycoplasma bovis operates a bit like a chameleon,” Cooper says. “The organism lacks a cell wall, and has variable surface proteins, so mycoplasmas can assume many forms and are very good at evading the calf’s immune system.”

The lack of a cell wall also makes treatment more difficult.

“Symptoms must be caught very early for treatment to be effective,” Cooper says. “Mycoplasmas will begin forming communities within the lung, and once those communities are formed, it becomes very difficult for an antibiotic to penetrate the lesion and control the mycoplasmas.”

Management practices for BRD mitigation include:

Minimize commingling where possible and segregate groups based on age, sex and arrival date.
Provide good ventilation and avoid overcrowding.
Maintain proper sanitation of equipment and pens.
Provide adequate nutrition with fresh feed and clean water.
Use low-stress cattle handling techniques.
Provide adequate shelter and avoid dusty environments.
Consult your herd veterinarian for operation-specific strategies.

“We need to focus on doing all of the small things well,” Cooper says.

She encourages producers to work with their herd veterinarian to identify opportunities for improving calf management to limit the risk of M. bovis and other disease-causing pathogens.

Preventing BRD caused by M. bovis through vaccination

Helping to prevent M. bovis infection includes focusing on a calf’s environment and a vaccination program.

“Depending on your management practices and disease prevalence, Protivity may be a great fit for your herd,” Cooper says. “But a solid vaccination program only works if other preventive practices that prioritize calf well-being are also in place.”

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Unlocking Success with Cow Herd Health Metrics: A Scorecard Approach

Tue, 27 May 2025 17:44:23 GMT

Tracking performance and evaluating herd success is a year-round process. Similar to tracking athletes, consider developing a scorecard to monitor your herd. Understanding how your herd is performing throughout the year is important when considering management, nutrition and culling decisions.

The first scorecard suggested was post-calving ; the next one to consider is herd health metrics. Illness and death loss in a cow herd are situations cattle producers must routinely address.

To help producers know where their herd health metrics should be, experts at Kansas State University’s Beef Cattle Institute offered some guidelines during a recent “Cattle Chat” podcast .

“The first metric in cow-calf operations that I look at is the first treatment response percentage,” says Brian Lubbers, K-State veterinarian.

He recommended producers aim for an 85% to 90% treatment success rate when treating one of the most common illnesses: Bovine Respiratory Disease, also referred to as BRD. He says that metric can be deceiving.

“Producers who aggressively treat BRD cases are likely treating some animals that didn’t have BRD, and that leads to a high spontaneous recovery rate,” Lubbers says. “If you are seeing a 100% first treatment success rate, you may be treating some animals who didn’t need the treatment. Very high treatment response rates should at least trigger a conversation with your veterinarian about case definitions.”

K-State veterinarian Bob Larson says another metric that producers should be aware of is the percentage of death loss in the calves. During the first year of life, there are three key times when calves are more susceptible to death: at birth, between birth and three weeks of age, and from about one month to weaning, he says.

For each of these periods, producers can expect a 1% to 2% loss, Larson explains, however, that percentage will vary from year to year.

“In the first year of life, difficult births, scours and pneumonia are some of the reasons that calves get seriously ill and sometimes die,” Larson says.

K-State beef nutritionist Phillip Lancaster says what he monitors in the herd is the body condition of the cows.

“If the cows are receiving good nutrition and maintaining their body condition, that is an indicator of the overall health of the herd,” Lancaster says.

Along with those metrics, Logan Thompson, K-State beef cattle extension sustainable grazing specialist, recommends producers treat the herd against parasites as part of an overall wellness program.

“Treating the herd against parasites is an easy win from a production efficiency and cattle longevity standpoint, and it increases the rate of passage of grass through the rumen,” Thompson says. “It is a hard metric to measure, but in some herds, cattle that are treated for parasites have an increased efficiency between 20[%] to 30%.”

In summary, the key takeaways from the podcast are:

Health metrics are multifaceted and require careful tracking.
Different perspectives (veterinary, nutritional, sustainability) offer comprehensive insights.
Metrics should be specific, measurable and contextualized.
Collaboration with veterinarians is crucial for effective health management.

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Cool Calves Live Longer

Thu, 03 Apr 2025 19:18:50 GMT

The average number of lactations of a U.S. dairy cow currently rests at about 2.8, or around 5 years of age.

That’s a fairly shocking statistic, considering a cow’s natural lifespan can be up to 20 years or more. And, on average, it takes about two full lactations before heifers begin to generate return on investment for their rearing or purchase cost. Given today’s robust heifer values, that time before young cows begin to pay the bills may be even greater.

So, how can we help cows live longer, more productive lives? Researchers at the University of Florida assessed one factor: birth season. They predicted that cows that entered the world during seasons of heat stress would have shorter lifespans. And they were right.

The study, led by researcher Izabella Toledo and published in the Journal of Dairy Science , examined the DairyComp records of more than 10,000 cows in Florida and 8,000 in California that remained alive and productive for more than 5 lactations.

The data were sorted to identify animals born over a period of 10 years (2012-2022) in the cool season (December, January, February, and March) and the hot season (June, July, August, and September). Cows born in the more temperate months of April, May, October, and November were not included in the dataset.

In Florida, 14.5% of cows (1,567) born in the test months were still alive and milking after 5 lactations. Of them, more than double (1,129, or 72%) were born in the cool months compared to the hot months (438, or 28%). In California, 20.4% (1,669) of the dataset made it 5 lactations or longer, with 56.% of them born in the cool months, versus 44% born in the hot months.

The Florida dataset also was analyzed for the number of cows born in the tests months that were dead or sold for beef in the first 4 lactations, and the reasons why. A total of 1,454 were sold and another 238 died. Selling reasons included breeding, foot and leg, digestive, and respiratory issues, along with mastitis.

Significantly more cows born in the hot season (53%) compared to the cool season (47%) were sold for beef.On-farm deaths also were significantly higher for cows born in the hot (54%) versus cool (46%) season.

Toledo and her team concluded that the results give even more credence to the deleterious impacts of heat stress on dairy productivity. Previous studies – many also conducted by University of Florida researchers – have shown that heat stress during late pregnancy affects dams’ milk production in the next lactation, immune function, and calf birth weight.

Further, they have found that calves exposed to heat stress in late gestation had 19% lower milk production in their own first lactations, and even passed that lower milk production potential on to their offspring.

Toledo said the results of the current study suggest a potential two-pronged approach to protecting the productive life integrity of newborn heifers: (1) implement heat-stress abatement measures for dams, including shade, fans, soakers, and misters; and (2) alter breeding decisions to avoid births in seasons of peak heat.

Your Next Read: A New Kind of AI for Dairy Calves

Five Easy Maternity Pen Moves for Better Calves

Mon, 08 Jul 2024 21:47:47 GMT

What happens in the maternity pen, does not stay in the maternity pen. Rather, the events and environment there can impact a newborn calf for the rest of its life, particularly when it comes to respiratory disease.

Because lung damage in calfhood can impact lifelong health and performance, researchers at the University of California-Davis conducted a multi-phase, large-scale population study examining various management factors and their influence on calfhood bovine respiratory disease (BRD).

On a recent episode of the “ Have You Herd ?” podcast from the American Association of Bovine Practitioners, Dr. Sherif Aly, veterinarian and epidemiologist at the UC-Davis Veterinary Medical Teaching and Research Center at Tulare, Calif., discussed the results.

Aly said the first portion of the study was a survey with more than 40 questions issued to dairies throughout California that helped narrow down the management factors that affect BRD. The next phase, dubbed the “BRD 100” study, drilled deeper into those issues on 104 cooperating dairies. Finally, the resulting information led to the “ BRD 10K ” study, which gathered health and performance data on more than 11,000 calves from birth to weaning on 5 dairies located in the 3 major milksheds in California.

In that study, management practices were assessed by risk factors that contributed to BRD in varying degrees. A score of 1.0 or higher indicated a risk factor. Of particular interest was the maternity pen, where the following risk factors were identified:

(1) Cows and heifers calving together – Commingling first-calf heifers in the same maternity areas as multiparous cows resulted in a BRD offspring risk factor of 1.4, meaning there would be a 40% greater likelihood of calves contracting BRD.

(2) Bedding changes – Changing the maternity pen bedding 6, 7, or 8 times per month significantly reduced the risk of calves contracting BRD. Interestingly, changing the bedding 9 times per month actually produced an uptick in BRD risk to calves.

(3) Bedding materials – Compared to dried manure solids mixed with gypsum, both dirt and plant-based bedding materials (rice hulls, almond hulls, straw, and wood shavings) showed higher risk factors for BRD. Dirt had a whopping 4X odds ratio compared to a manure solids/gypsum base.

(4) Pasture calving – Calving on pasture produced a higher risk factor for BRD compared to enclosed maternity pens.

(5) Dam separation – Removing calves from their dams within 1 hour of birth produced a significant reduction in BRD risk.

The study also examined the association of BRD incidence related to herd demographics, colostrum delivery, vaccination, nutrition, and housing.

Aly said BRD is a complex, multi-factorial disease, lamenting that the incidence in dairy calves has not improved significantly over several decades. His team’s work revealed that 22-23% of calves contract BRD in the preweaning period, which leaves much room for improvement.

By drilling deep into the management practices and related BRD incidence on California dairies, Aly is hopeful the data and knowledge gleaned from their work can help dairies reduce their struggle with the disease. “BRD in preweaning period sets the stage for the success of these cows later on in life,” he declared.

Legislators Reintroduce Bill to Recruit and Retain Veterinarians in High-Need Areas

Thu, 27 Mar 2025 20:44:19 GMT

The Rural Veterinary Workforce Act, bipartisan legislation to help recruit and retain veterinarians in underserved and rural areas, was reintroduced by Senators Mike Crapo (R-Idaho) and Tina Smith (D-Minn.) and Representatives Adrian Smith (R-Neb.) and John Larson (D-Conn.).

“In nearly every state in the country, there are shortages for veterinarians, especially in rural areas,” Sen. Smith says. “This record shortage causes serious harm to the health of animals and the public. Providing additional funding to the Veterinary Medicine Loan Repayment Program (VMLRP) and updating the tax code to better serve veterinarians will allow more qualified vets to do vital work with our animals in underserved communities.”

Strongly endorsed by the American Veterinary Medical Association (AVMA), this would expand the reach and maximize the allocated funding of the highly successful VMLRP, which can help to attract veterinarians in USDA-designated veterinary shortage areas by assisting with the significant obstacle of educational debt. It would also end the federal taxation on VMLRP awards, allowing more veterinarians to participate in a program that offers up to $120,000 over three years for student loan repayment in exchange for service in one of the designated shortage areas. In addition, it would align the tax code with human and other healthcare professions’ award funds.

“Veterinarians are vital to the work of America’s farmers and ranchers and the integrity of our food supply chain. Yet many areas of the country suffer from lack of access to their services,” Rep. Smith says. “This bipartisan bill would make commonsense tax relief available to veterinarians who choose to live and work in the communities which need their help to care for their livestock and protect the agriculture industry from pests and disease. I thank my colleagues for joining me in reintroducing it.”

In 2025, the USDA declared 243 rural veterinary shortage areas in 46 states, which is the highest number of shortage areas ever, AVMA said in a release. Since 2010, the USDA has awarded 883 VMLRP awards to veterinarians; meanwhile, 2,197 applications have been received to participate in the program since its inception.

“Recruiting and retaining veterinarians through the Rural Veterinary Workforce Act is key to protecting our nation’s food supply, preserving animal welfare, and upholding public health,” Sandra Faeh, AVMA president, said in a release. “Livestock and public health veterinarians are essential to strengthening the nation’s animal health infrastructure and agricultural economy. We urge Congress to address this increasingly important issue by passing the Rural Veterinary Workforce Act.”

Your next read: Is the Swine Industry Ready for H5N1? Texas Veterinarian Says “No”

Count the Costs of Lameness in the Cowherd

Wed, 19 Mar 2025 17:48:26 GMT

Two steps forward and one step back might best describe the progress the dairy industry has made to address the issue of lameness in the U.S. cowherd. While progress has been made, the problem is still too prevalent, according to Nigel Cook, professor of food animal production medicine at the University of Wisconsin.

“If you talk about physical well-being, I think lameness and hock injuries are the No. 1 and No. 2 issues on the farm (in that order),” he says.

Cook says the issue of lameness specifically is under-reported on dairy farms, as producers underestimate the prevalence of it and tend to overlook those cows that are mildly lame. Based on research and experience, he estimates about 22% of U.S. dairy cows walk around the farm with a noticeable limp.

“I think that’s something we really need to do something about,” he told Fred Gingrich, DVM and Executive Director of the American Association of Bovine Practitioners (AABP), during a recent “Have You Herd?” podcast.

Cook says when he and his team do welfare audits and lameness assessments, the farmer is often focused on the animal unable to bear weight, while he and his team will look for any animal that has weight-transfer challenges or pain associated with their limbs.

“I think that’s where a sort of disconnect comes into play; the farmer thinks their lameness issue is under 5%, while when we go out and look it’s often 25%,” Cook says.

Even mild pain that cows experience with lameness impacts milk production, health and well-being. In addition, lameness can change the structure of a cow’s hoof and increase the risk of further lameness incidents in the future.

Lameness Is A Costly Issue
Penn State Extension has calculated the cost of lameness and shared that information in an online article: Lameness: It’s Costing You

Researchers (Dolecheck and Bewley, 2018) estimated that lameness can cost between $76 and $533 per case, in 2023 dollars.

A study published in the April 2023 edition of the Journal of Dairy Science (Robscis et al., 2023) investigated the economic impacts of lameness in dairy herds. The model used in this study considered reproductive status, milk production, parity, stage of lactation, and interaction with other diseases. This model also considered whether the cow was newly or chronically lame.

When considering how much lameness costs a farmer, Robscis et al. (2023) included a loss in milk production, changes in reproduction, and treatment costs. This study suggested that it costs an average of $336.91 per case of lameness.

Digital dermatitis was the largest cause of lameness and cost almost $100 more than other causes of lameness, the Penn State article reports. For each additional week that a cow remained lame, it cost the farmer $13.26 more per week.

Lameness Affects Routine Cow Behavior
Cook says the three issues most often contributing to lameness are digital dermatitis, white line disease and sole ulcers, Cook says. On larger dairies, another issue he would add to the list is thin soles.

“As we walk cows on concrete, sometimes up to a half mile a day, it basically wears the sole away. Those thin soles can be associated with lesions in the toe, what we call toe ulcers,” he explains.

Cook told Gingrich that concrete has a low coefficient of friction, meaning less force is needed on the surface of concrete for slipping to occur. “So as the cow starts and stops, they tend to slide. Concrete doesn’t have a supporting structure like the cow has on pasture.”

Once a cow becomes lame, she behaves differently because of the pain she feels in her legs and/or hooves. Depending on pain severity, the cow can get stuck in a lying down position when she wants to stand, and she can get stuck standing when she wants to lie down.

“It’s that transition from standing to lying and then lying to standing that they really have trouble with,” Cook says.
Putting down rubber isn’t a cure-all for flooring issues, either. While it can reduce contusions to soft tissue and pressure on the foot, it can increase the risk for sole hemorrhage and sole ulcers.

“The best flooring surface is one that a cow doesn’t stand on for half the day, and that means getting her in the stall and resting because that reduces pressure,” Cook says. “Once we’ve got the stall surface set, the design of the stall, a comfortable place to lie down, you can put rubber wherever you like after that, but get the lying space fixed first.”

Cook says he sees barns that have large quantities of concrete flooring, but that it works OK because the farmer has done a good job of providing stall comfort. “Then, strategically, you can use rubber in places where we force cows to stand, such as in the parlor and the holding area.

Evaluate Cow Lying Time
Lying time is a major factor in preventing lameness, improving cow comfort and returning lame cows to soundness. The amount of lying time a cow has is a good clue to whether the dairy is allowing her to have optimized resting behavior.

“That’s basically the notion that cows get to lie down when they want to,” Cook says. “It’s not necessarily just hours a day. It’s that sort of freedom to choose a place to rest and then get adequate rest on that given day.”

There are some correlations between the amount of time the cow spends lying down, resting, and the amount of lameness that occurs or whether it occurs.

“The first is animals get lame from spending too long a time standing, putting too much load on the suspensory apparatus of the claw and creating things like sole hemorrhage and sole ulceration because of that increased loading,” Cook says. “What we know now is once a cow has those structural changes (in the hoof) they’re permanent, and that can put those animals at risk of repeated episodes of lameness.”

Through research, Cook was also able to determine that reduced lying time in early lactation is a risk factor for core lesions that occur later in lactation. “It took us some time, but there are some really key, pivotal studies that elegantly show that,” he says.

Overstocking Has Long-Term Consequences
Cook encourages dairy producers to look for balance in how much time cows spend in and out of stalls.

“We want the cow to spend no more than three to three-and-a-half hours a day out of the pen,” Cook says. “Otherwise, we compromise the ability of the cow to access the stall and rest for 11.5 to 12.5 hours a day, which we think is somewhat normal in a freestall environment.”

He adds that when he assesses farms that are having lameness issues, he often finds scenarios where the cow is spending five or six hours a day out of the stall due to over-stocking.

“We commonly go into herds that have 1.3, 1.5 cows per stall and while many farmers can manage their herds amazingly well at those high stocking rates, you are compromising lying time and that will catch up with you eventually,” he explains.

Another common issue is when the dairy producer is using stalls that weren’t designed for the current cow size, or if there’s a lack of manpower needed for adequate turn times.

“I’ll just add if you’ve got a robot, you don’t get let off the hook there, because we found in free-flow herds, there are subordinate animals that struggle to access the robot,” Cook says. “They get out-competed at the swing gate and they can be waiting for four or five, six hours a day to milk, even in a robot facility. So that’s another area where we find rest compromised.”

Cook and Gingrich encourage dairy veterinarians to be involved in lameness prevention and improving cow comfort on the farm by performing lameness audits and reviewing hoof trim records. They recommend using a time-lapse camera to help in the process of monitoring cow behavior, insights that farmers can then see for themselves. Time-lapse cameras are available on Amazon with a starting price point of $150.

Cow-attached sensors or accelerometers can also measure lying behavior and activity when attached to the leg and can track rumination and eating when attached to the neck, Penn State Extension reports. These types of sensors are also widely used for heat detection. Learn more at Impacts of Lameness – Preventing Lame Cows

Maximize Stall Comfort
Stall surface plays a significant role in the ability of the compromised cow to transition between standing and lying down. Good cushioning, traction and support allow the animal to stand or lie down and rest normally.

Cook is a proponent of using deep sand bedding in stalls. “It’s associated with about a 40% reduction in lameness, largely because it helps optimize resting behavior,” he says. “It’s also a better, more attractive surface in the alleyways, and maybe reduces the risk for white line.”

During their discussion, Gingrich recalled one time when Cook had told him that banning mattresses would have a significant, positive impact on improving cow welfare.

“That might have been said a little tongue in cheek, but it’s probably true,” Cook told Gingrich.

While Cook says he has worked with herds on mattresses that have low levels of lameness, it’s usually thanks to a proactive manager who identifies lameness issues quickly and gets cows treated.

Cook reiterated that he believes the gold standard for providing cushioning for cows is a deep bed of sand. The sand conforms to a cow’s bony features and reduces the potential for hock injuries when she changes position.

“When she chooses to get up and down, she’s got that cushion, traction and support to be able to do that even in a situation where she’s compromised and has a sore foot,” Cook says.

Gingrich saw similar benefits when he was in private practice.

“My producers that constructed new barns or remodeled their stalls, and converted to sand, they pretty much all have said their major problems seem to go away,” Gingrich recalls. “Mastitis in milk quality improved, production improved more consistently, lameness, as you said, significantly decreased, even culling was reduced. We just had fewer broken cows.”

Additional Bedding Considerations
While Cook likes using sand in stalls, he notes it does have some limitations and can pose challenges, too. “I readily admit sand gets everywhere and can hurt manure pumps and various other things,” he says.

The new kid on the block that some dairy farmers are evaluating is the use of a deep bed of recycled manure solids. But it has drawbacks to consider, as well.

“When you’re dealing with an organic compound versus an inert, inorganic compound, you have potential for bacterial growth issues,” Cook says.

Notes Gingrich: “We want to improve cow comfort, but we don’t want to create another problem with our bedding type, in the process.”

“I think one of the lessons learned is it’s got to be drier than the material that comes out of the screw press,” Cook adds. “And that means using some kind of a supplemental drying process that takes us to, in our climate here, about 50% dry matter. That percentage of dry material seems to behave a whole lot better than the 70% moisture, 60% moisture material that comes out of screw presses.”

Stall dimensions that allow cow movement are another important consideration for producers to consider as they address lameness. Cook says cows need enough room to “lunge and bob.” Essentially, they need freedom of movement in a space so they aren’t restricted, but he adds that having the freedom to move needs to be balanced with the need to keep cows clean.

Don’t Overlook Environmental Stresses
Cook says when he first started his career, he thought if he could create the perfect stall the cow would lie down even in overly warm conditions. That was not the case. Instead, what he learned was that good ventilation and the ability of a cow to be cool in hot weather conditions is critical.

“Even in a good environment or circumstance, when heat comes along heat-stressed cows end up standing for protracted periods of time,” he explains.

Cook encourages dairy producers when they’re building barns or remodeling facilities to focus more on the cow and less on how they will handle manure or implement other processes.

“Focus on the cow,” he says. “That’s the big thing. Cow comfort is that important.”

Gingrich advises producers and veterinarians to visit other dairy farmers to learn what works for them that they might be able to take home and use.

Cook says he agrees, noting that farmers are often the best resource to help other farmers who are struggling with making decisions about adopting a new management practice.

More informational resources and tools are available online from Cook and his team at the Dairyland Initiative.

Links: The Dairyland Initiative Dairyland Initiative Podcast and other resources can be found here .

You can hear the complete discussion between Drs. Cook and Gingrich on “Have You Herd?” at this link: Epi. 221 – Making Cows Comfortable to Improve Lameness and Welfare