Pasture-Forage

10 Toxic Pasture Weeds: How To Identify and Manage

Thu, 24 Jul 2025 20:22:29 GMT

Not all toxic plants are equally dangerous, and many factors, such as stage of growth, part of the plant consumed and quantity, play a role in whether animals are affected.

With the ongoing weather variability the past few years, pasture conditions have been highly inconsistent. Some are thriving, while others are struggling due to overgrazing, flooding or drought.

“When pastures thin out, they leave space for opportunistic weeds to move in,” Shelby Gruss, Iowa State University Extension forage specialist, says. “While all weeds can compete for light, nutrients and moisture, some pose a greater threat due to toxicity risks for livestock.”

Below is a list of some of the most common toxic pasture weeds in Iowa and the Midwest, with tips on identification:

Poison Hemlock

(Kevin Bradley)

Poison Hemlock (Conium maculatum)
Toxic Part: Entire plant, especially leaves and stems
Risk: Highly toxic to all livestock (and humans); small amounts can be fatal
ID Tips: Finely divided, fern-like leaves; purple-spotted stems; umbrella-shaped white flower clusters
Notes: Often found in ditches and low-lying areas; do not mow when flowering — can release toxins and spread seeds
Common look-a-like: Queen’s Anne Lace/wild carrot

Wild Parsnip (Pastinaca sativa L)

(John Cardina, The Ohio State University, IPM Images)

Wild Parsnip (Pastinaca sativa)
Toxic Part: Sap causes skin irritation when exposed to sunlight (phytophotodermatitis)
Risk: Mainly a risk to humans (and pets) through skin contact; generally avoided by livestock, but ingestion can cause photosensitivity and severe sunburn
ID Tips: Yellow umbrella-shaped flowers; hairy and grooved stems; leaves look like celery or parsley
Notes: Wear gloves and long sleeves when handling; mowing before seed set helps control
Common look-a-like: Queen’s Anne Lace/wild carrot

Common St. Johnswort (Hypericum perforatum L.)

(L.L. Berry, IPM Images)

St. Johnswort (Hypericum perforatum)
Toxic Part: Entire plant
Risk: Contains hypericin, which causes photosensitivity (sunburn-like skin damage) in light-skinned livestock such as sheep, cattle, goats and horses; severe cases can lead to skin sloughing, blindness or death
ID Tips: Upright perennial with small flowers; the flowers have five bright yellow petals that often have black dots on the petal margins; leaves are opposite, oval and have translucent spots when held up to light; woody base; grows 1' to 3' tall in clumps
Notes: Becomes more problematic in overgrazed or low-fertility areas. Most toxic when flowering. Often avoided unless forage is limited

Common Milkweed

(Kevin Bradley)

Common Milkweed (Asclepias syriaca)
Toxic Part: Leaves and stems
Risk: Contains cardiac glycosides; toxic in large amounts, especially to cattle and sheep
ID Tips: Thick oblong, opposite arranged leaves; milky sap; large round pink flower clusters; stems covered with dense pubescence
Notes: Generally unpalatable unless forage is scarce; monitor pasture for adequate forage growth

Johnsongrass

(Kevin Bradley)

Black Cherry (Prunus serotina) / Johnsongrass (Sorghum halepense)
Toxic Part: Wilted leaves (Black Cherry); young regrowth and frost-damaged tissue (Johnsongrass)
Risk: Both produce cyanide (prussic acid), which can be fatal within minutes
ID Tips (Cherry): Tree with shiny leaves, dark bark, and white flowers
ID Tips (Johnsongrass): Tall grass with prominent midrib, purple panicle seeds, spreads rhizomes
Notes: Do not allow livestock access to wilted branches or frosted regrowth; delay grazing after frost or drought
Common look-a-like (Johnsongrass): Sorghum species

White Snakeroot (Ageratina Altissima)

(Ansel Oommen, IPM Images)

White Snakeroot (Ageratina altissima)
Toxic Part: Entire plant
Risk: Causes “milk sickness” in humans through milk from affected cattle; toxic to cattle, goats, horses
ID Tips: Opposite triangular leaves with serrated edges (sharply toothed) with three main veins; white flowers in flat-topped clusters
Notes: Common in wooded pastures or shaded edges; control early; avoid grazing densely infested areas
Common Look-a-like species: bonesets, other snakeroots

Horsenettle (Solanum Carolinense)

(Kevin Bradley)

Horsenettle (Solanum carolinense)
Toxic Part: Berries and leaves
Risk: Contains solanine; can affect the nervous system and digestive tract
ID Tips: Spiny stems and leaves; small, star-shaped purple flowers; yellow berries when ripe
Notes: Toxic when consumed in large amounts; spot spray or dig out to reduce spread; berries are particularly toxic

Cocklebur

(Kevin Bradley)

Cocklebur (Xanthium strumarium)
Toxic Part: Seeds and seedlings
Risk: Toxic to pigs, sheep and cattle; seedlings are especially dangerous
ID Tips: Rough stems with darks pots; sandpaper-like, triangular leaves with serrated leaf edges; hooked burs that cling to fur and clothing
Notes: Can cause liver damage; avoid overgrazing, as seedlings are more likely to be eaten when forage is limited

Pigweed (Genus Amaranthus L)

(Howard F. Schwartz, Colorado State University, IPM Images)

Nitrate Accumulators
Some plants can accumulate toxic levels of nitrates, especially after drought or heavy fertilization:
Common culprits: Pigweed, lambs quarters, Johnsongrass, and thistles
Risk: Nitrate poisoning reduces oxygen transport in blood — can be fatal
Management Tip: Have suspect forages tested before grazing or feeding; elevated risks following fertilization, and following drought breaking rains

Field Horsetail (Equisetum Arvense L)

(John Cardina, The Ohio State University, IPM Images)

Horsetail (Equisetum spp.)
Toxic Part: Entire plant
Risk: Contains thiaminase; can cause neurological symptoms, especially in horses
ID Tips: Hollow, jointed stems; no true leaves; resembles a bottle brush
Notes: Grows in poorly drained soils and along ditches; improve drainage and limit access

“The first step to weed management is identifying the species you have in your field,” Gruss says.

If you’re unsure about a plant in your pasture, contact your local field specialist.

“When in doubt, better safe than sorry — keep animals away until you’ve confirmed safety,” she summarizes. “Typically, animals will avoid toxic species when there is something else to graze, but eliminating the toxic weed species is ideal. If using herbicides, please read and follow all herbicide directions and grazing restrictions.”

More information on common pasture weeds can be found here: Recognizing and managing common pasture weeds .

More information can be found here: 2025 Herbicide Guide: Iowa Corn and Soybean Production for herbicides labeled for grass pasture, hayfield (table 6) and alfalfa and legumes (table 7).

Spring Pasture Growth Raises Grass Tetany Risk in Beef Herds

Tue, 24 Mar 2026 17:07:12 GMT

As spring moisture and fluctuating temperatures drive a surge in forage growth, conditions are aligning for an increase in grass tetany risk across many beef operations. The same environmental shifts that are jumpstarting wheat pasture and other small grains can also create the mineral imbalances that trigger sudden losses in lactating cows.

With rapid pasture growth underway in many areas, grass tetany risk is rising in susceptible herds, according to Paul Beck, Extension specialist for beef nutrition with Oklahoma State University. High-quality forage is often directed toward cows with the greatest nutritional demands, placing early-lactation animals directly into higher-risk environments.

Fertility and Forage Growth Driving the Issue

Cool-season annuals are a valuable resource, particularly when they reduce reliance on hay and supplemental feed. But as pasture quality improves, mineral balance can shift in ways that are not immediately visible.

“Our best managed cool-season annual pastures have had adequate fertilizer high in nitrogen and potassium, both of which are necessary for grass growth. But high nitrogen and high potassium interacts with the marginal magnesium level in these forages and create issues with beef cows as they begin lactating,” Beck says.

Nitrogen and potassium fertilization support aggressive forage growth, particularly during periods of favorable moisture. At the same time, they can interfere with magnesium uptake, leaving cows vulnerable even when forage appears nutritionally rich.

Magnesium absorption occurs primarily in the rumen and can be impaired by high potassium levels, which reduce transport across the rumen epithelium. This is why fertilized, rapidly growing forages create a consistent risk pattern.

Periods of rain followed by rapid pasture growth can further amplify the risk, especially when cattle are transitioned quickly onto highly digestible forage.

Early Signs Easy to Miss as Cases Develop Quickly

Grass tetany remains a neurologic condition driven by low blood magnesium, and clinical signs can escalate rapidly once levels fall.

“Cows will start shaking and have uncontrolled muscle movements. They will lose their balance. That will be one of the first signs you see,” Beck says.

In the early stages, affected cattle may appear nervous or uncoordinated. As the condition advances, animals can go down and become unable to rise, with death occurring shortly after if intervention is not successful.

Because of this rapid progression, cases are often first recognized only after severe signs appear.

Early treatment with intravenous or subcutaneous calcium-magnesium solutions can be effective, particularly before animals become recumbent. Relapses are possible, and animals should be monitored closely following initial treatment.

Grass tetany should be differentiated from other causes of neurologic signs and sudden death, including hypocalcemia, polioencephalomalacia, and lead toxicity. History, pasture conditions and response to magnesium therapy can help support a presumptive diagnosis in the field.

Prevention Hinges on Timing, Not Reaction

Despite the speed at which grass tetany can develop, the risk itself is highly predictable. That makes prevention the most effective strategy, particularly during periods of rapid pasture growth.

“The best way to counter the problem is to act before we get to it,” Beck says.

That means preparing ahead of turnout, not reacting after symptoms appear. In practical terms, that looks like identifying high-risk pastures and production stages in advance, then ensuring supplementation is in place before cattle enter those environments.

This is especially important during spring transitions, when forage conditions can change quickly over a short period of time.

Mineral Intake Remains the Weak Link

While most producers are aware of the need for high-magnesium mineral, consistent intake remains the primary challenge.

“Magnesium oxide does decrease the palatability of mineral mixes, making it important to manage the feeding of these minerals,” Beck says.

Magnesium oxide is widely used due to its availability and cost-effectiveness, but reduced palatability can limit voluntary intake. Without active management, even well-designed mineral programs may fall short.

Management Focus as Risk Window Opens

With pasture conditions improving and turnout underway or imminent in many areas, attention is shifting toward practical prevention.

Risk mitigation should focus on:

Ensuring high-magnesium mineral is available before and during turnout.
Monitoring intake closely, rather than assuming consumption.
Placing feeders in high-traffic areas to encourage consistent use.

A Seasonal Risk That Follows Predictable Patterns

Grass tetany tends to emerge when rapidly growing forage, high-producing cows and inadequate magnesium intake intersect. Spring conditions consistently bring those factors together, making this a predictable — yet preventable — challenge.

Outbreaks often affect multiple animals within a short timeframe, particularly when herd-level mineral intake is inconsistent. This makes grass tetany both an individual animal emergency and a herd management issue.

Timely supplementation and close management of intake can help you stay ahead of the problem before clinical cases begin to appear.

After the Fire: The Need for Feed, Fence and Prayers

Mon, 23 Feb 2026 21:19:00 GMT

Wildfires plagued the Plains last week from southern Kansas into Oklahoma and Texas. Hundreds of thousands of acres of grass are now burned to sand.

The Ranger Road Fire, which started in Oklahoma and made its way into southern Kansas, to date has burned more than 283,000 acres and is 65% contained as of Monday morning, according to the Oklahoma Department of Agriculture, Food and Forestry .

The Oklahoma Forestry Services reports moderated fire weather over dormant fuels resulted in a downtick in wildfire activity over the weekend, allowing firefighters to improve the containment of recent large fires.

“Conditions also supported opportunity to execute burn plans for prescribed fires,” the report says. “If you engaged in prescribed burning, controlled burns or pile burns over the weekend, please ensure that fire perimeters are mopped up and secured ahead of increasing fire weather concerns Tuesday through the remainder of the week.”

Read more about how strong winds, above-average warmth and months of worsening dryness created a “perfect recipe”

for wildfires across the Southern Plains, scorching pasture and farmland — with little moisture relief in the forecast:

Why the Southern Plains Became a ‘Perfect Recipe’ for Wildfire

The wildfires have left a path of heartbreak and devastation. From the loss of livestock and homes, barns and shops to pastures and fence, the damage is hard to fathom.

Oklahoma Secretary of Agriculture Blayne Arthur visited Oklahoma producers impacted by the wildfires on Thursday. “Please pray for our farmers and ranchers and our first responders who continue to battle challenging fires and weather,” she says.

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Secretary of Agriculture Blayne Arthur

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Secretary of Agriculture Blayne Arthur

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Secretary of Agriculture Blayne Arthur

Dr. Randall Spare, Ashland Veterinary Center Inc., says nine years after the losses resulting from the Starbuck Wildfire — still the largest, most extensive wildfire in Kansas history — many of the same ranchers have been affected by the Ranger Road Fire.

Spare explains the wildfire was unstoppable with little farmland or breaks to get ahead of the fire plus the extreme wind. The fire started near Beaver, Okla., at 11 a.m., and he reports many ranchers in the path were moving cattle by noon. He says the highest losses occurred where there were no nearby wheat fields or safe pasture alternatives for the cattle.

“When you have contiguous grass for 90 miles, and the fire line was 90 miles long, from Beaver, Okla. to Protection, Kan., and it was moving 70 miles an hour, it’s hard to get in front of it,” he says.

He also explains because of the good moisture in 2025 and good stewardship of the land, there was a lot of tall, dense forage to fuel the fire.

“Many of the best stewards — those who don’t overgraze and stockpile grass for calving and drought management — actually experienced some of the worst damage,” he explains. “Because they’ve done a good job of managing their grass and have forage to eat in the spring of the year before the growing season starts to calve on, they experienced some of the greatest damage.”

Spare says the Ranger Road Fire took the same path as the Starbuck Fire, but it did not burn as many acres in Kansas — about one-third less in comparison.

“The good thing is it did not go north of Ashland. It’s five miles south of Ashland before it starts and not near the acreage burned,” he summarizes. “Since it isn’t like the Starbuck Fire, we have an opportunity as neighbors to help neighbors, whereas before we couldn’t do that because we were all affected.”

He predicts producers in Kansas lost 1,000 to 1,100 head. He adds there will continue to be more loss as producers evaluate cattle condition.

“One of the biggest damage is feet,” he explains. “The walls of their hooves start to fall off due to the fire. And sometimes that doesn’t show up for five days.”

How Can You Help?

According to Reuters , other fires have burned thousands more acres in Oklahoma, Kansas and Texas.

In agriculture, community is strong. When one producer hurts we all feel it and, if possible, we step up and help our neighbors in need. Along with prayers, Spare adds the immediate needs are:

Hay
Money (financial support)

In response to producers offering help, Spare shares a list of ways others can support ranchers recovering from the wildfires on social media, including lessons learned from the Starbuck Fire.

“I would like to share what we learned from the Starbuck Fire that, hopefully, will be helpful as you consider making decisions about how to help,” he writes.

Fencing supplies: “After the Starbuck Fire, we learned that if federal funds are used to rebuild and replace fences, the construction requirements to access those funds are very specific regarding type of wire, posts, etc. While the generosity of those giving nine years ago was remarkable, we were limited in how much of the donated resources actually could be used simply because federal loss recovery funds needed to be used, and the donated fencing supplies didn’t meet government specifications.”
Money: “Today, money is the most precious resource and in the greatest need. Many of the ranching operations affected need time to truly assess their losses. Some are finding cattle they first thought to be lost, alive and safe. Others are experiencing the opposite and unfortunately are seeing the losses increase.”
Available pasture and grassland: “If you have pasture available either short term or long term, please reach out to Ashland Community Foundation, Kansas Livestock Association or Ashland Veterinary Center,” he suggests.
Hay: There are designated drop off locations ready to accept loads of hay.

Multiple organizations have stepped up and are organizing supplies and assistance.

• Kansas Livestock Association. KLA is helping connect those wishing to donate with the most suitable drop location. If you’re hoping to donate goods including livestock feed or hay, you can contact KLA at (785) 273-5115, or visit this website . On KLA’s Facebook page you can find posts from feedlots that are offering pen space to wildfire victims.

• The Ashland Community Foundation. ACF is accepting monetary donations to help those affected by the fires in their community. To donate, please visit the ACF website and select “Become A Partner” in the dropdown. Donations are also being accepted at Stockgrowers State Bank or can be mailed to ACF at P.O. Box 276, Ashland, KS 67831.

• Oklahoma Cattlemen’s Foundation. OCF has established a relief fund to help cattle producers who have been affected. As the 501(c)(3) charitable arm of the Oklahoma Cattlemen’s Association, the fire relief fund at the Oklahoma Cattlemen’s Foundation will distribute 100% of received funds to affected cattle producers. You can give online or make checks payable to Oklahoma Cattlemen’s Foundation with “Fire Relief” in the memo line and mail to P.O. Box 82395, Oklahoma City, OK 73148.

• Beaver County Stockyards and Beaver County OSU Extension office. For those willing to donate feed or hay to the Beaver County, Okla., area, visit the Stockyards website or the Extension office website .

• Beaneighbor.org . The Oklahoma Healthcare Authority, provides access to local support including financial assistance, food pantries, medical care, and other free or reduced-cost help. Search for aid in your area at Beaneighbor.org.

Oklahoma Department of Agriculture, Food, and Forestry reminds the public to use caution before bringing hay to northwest Oklahoma to prevent the spread of invasive fire ants. Find out if your county is under quarantine for fire ants on the USDA website

Fire Weather is Not Over: Stay Prepared

The Kansas Forest Service reminds producers there are still months of fire season to come.

“As firefighters continue to mop up or extinguish hot spots along miles of fire line, recovery begins for the communities most impacted by recent wildfires,” the agency says. “Many wildfire managers are already preparing for the next round of fire weather.”

While recovery and readiness are happening at the same time, the forest service share these two tips:

Learn how to prepare your home and property for a wildfire. Proper preparation can help your home withstand a wildfire.
Have a plan when the wildfire is heading toward your home or property.

Texas A&M AgriLife Extension has a Fires & Wildfires website dedicated to providing resources to help prepare for and survive wildfires.

A Note to Survivors

Spare says his message to producers who are recovering from the wildfires is to:

Think beyond today. Plan not only for immediate survival but for summer grazing and next winter’s feed. Recognize that hay now is also about having feed later, since grass is gone.
Don’t be afraid to ask for help. “If you are struggling, reach out to a trusted friend and accept neighbor and outside assistance,” he stresses.

Spare summarizes producers from his area are deeply appreciative and humbled by people from across the country who helped nine years ago and are helping again now, even to the point that local folks feel “almost embarrassed” it happened again.

“But it is life, and we’re going to trust God and go on,” he says.

Your Next Read: Tips for Care Following Wildfire

3 Nutritional Questions to Consider Prior to Calving

Fri, 16 Jan 2026 14:45:05 GMT

Supplying adequate nutrition to the cow is critical during the 60 days prior to calving and immediately after calving.

“Beef cattle can turn high fiber forages and food by-product residuals into protein food at a very effective rate,” says John Comerford, Pennsylvania State University professor emiritus of animal science, in a recent extension article . “For the cow herd, there is seldom a period during the year when the cow cannot meet her nutritional needs with reasonable quality grass, hay or stored forages. The exception for these nutritional needs is for the 60 days prior to calving and immediately after calving.”

Why Is There a Nutritional Challenge Prior To and After Calving?

Comford explains there are three major reasons why cows are challenged prior to and right after calving:

The initiation of lactation
The return to a fertile reproductive state
The production of colostrum

He adds the cow’s age has an impact on these factors, and younger cows have more critical nutritional needs.

Lawton Stewart, University of Georgia (UGA) assistant dean for extension, and Uttam Saha, UGA Agricultural & Environmental Services Lab (AESL) program coordinator, explain there are three nutritional questions producers should consider as calving season approaches — depending on forage availability and quality.

Does restricting feed in the last trimester decrease calf birth weights?
Do you need more protein to go with hay?
Are you underestimating crude protein and overestimating energy?

Does Restricting Feed in the Last Trimester Decrease Calf Birth Weights?

Stewart and Saha say yes, feed restriction will decrease birth weights. The problem is that birth weight is not the only thing it will affect.

Recent research has focused on fetal programming . Fetal programming is the concept that maternal stimuli or insults during fetal development have long-term effects on the offspring.

One of the most critical aspects of fetal programming involves the adequate nutrition, or lack thereof, of the dam. Research has shown minimal impact on calf birth weights; however, the restricted nutrition during the last trimester decreased weaning weights, finishing weights and hot carcass weights.

Additionally, research from Nebraska indicates heifers from nutritionally restricted cows reached puberty 14 days later than those with proper nutrition.

Do You Need More Protein to Go with Your Hay?

Stewart and Saha say possibly, however, protein is only half of the equation.

Figure 1: The nutrient requirement of a mature brood cow through a 365-day calving interval.

(UGA)

From April 1 to Oct. 1 of 2025, 773 bermudagrass hay samples were submitted to the UGA lab. The mean crude protein (CP) and energy (TDN) value was 11.1% and 55.7%, respectively. The illustration above represents the CP and TDN requirements of a brood cow throughout the production year. As cows enter the final trimester, their CP requirement is exceeded by the average bermudagrass sample, but the energy requirement falls short. More importantly, as they calve, enter peak lactation and the breeding season, the CP requirement is met, but the TDN falls tremendously short.

Do Producers Underestimate Crude Protein and Overestimate Energy?

Stewart and Saha say there is a tendency for producers to underestimate crude protein and overestimate energy.

“The cheapest money you will ever spend in a beef cattle operation is a forage test, guaranteed,” Saha says.

He explains a great illustration of this happened recently during the UGA Master Cattlemen’s Program. As part of the program, a free forage test was offered to participants along with a survey to estimate what producers thought the quality of the hay was prior to testing. This survey showed 83% of producers were underestimating the protein of their hay compared to the actual. This would result in purchasing a protein supplement when not needed.

For energy, 50% overestimated the level, resulting in depriving needed energy during late gestation and early lactation. In addition to the previously discussed fetal programming issues, this could also cause delayed breeding.

Figure 2: Actual example of over estimating energy.

(UGA)

An example of overestimation of energy is illustrated the example above. The overestimation could likely result in breeding being delayed 42 days. The resulting loss in weaning weight could easily reach 80 lb., leading to an approximate $280 decrease in value per calf.

“Through forage testing, the producer would know to feed 4 lb./day of a supplement such as corn gluten feed. Based on a 25-cow herd, this could easily return $6,325 above cost. That is a no-brainer,” Saha explains.

Brood cow nutrition is a crucial part of a beef cattle operation. Between fetal programming and maintaining the proper calving interval, it is imperative for producers to pay close attention to the nutrients available in their forages, and if they meet the requirements of their herd.

Your Next Read:
Ensuring Quality and Nutrition: Three Easy Steps For Forage Analysis
9 Tips to Ensure Calving Season Success
Your Calving Prep Starts Here: The Essential Checklist

When Cattle Don't Roam: Uncovering Tick Refuges with GPS, GIS and Modeling

Mon, 08 Dec 2025 20:00:46 GMT

Cattle fever ticks persist in South Texas not because eradication efforts have failed everywhere, but because, in some places, cattle never go at all. New research from Texas A&M combining GPS collar data, habitat mapping and individual-based simulation models shows areas rarely visited by treated cattle can function as ecological refuges for ticks, allowing populations to survive long enough to reinfest herds.

For more than a century, eradication programs targeting Rhipicephalus microplus have relied on a straightforward premise: treat cattle, interrupt the tick life cycle, and the population collapses. That approach nearly succeeded nationwide by the mid-20^th century, protecting the U.S. cattle industry from bovine babesiosis, a disease transmitted by the tick. However, in South Texas, particularly at the wildlife-livestock interface, ticks continue to persist despite regular treatment programs.

According to a pair of recent studies from Texas A&M AgriLife researchers, the missing piece might not be chemical efficacy or compliance, but behavior. Specifically, where cattle choose not to roam.

What GPS Tracking Reveals About Cattle Behavior

In the first study , cattle were outfitted with GPS collars to record fine-scale movement across the Texas coastal landscape known to harbor cattle fever ticks. Over extended periods, the researchers tracked when and where animals grazed, rested and avoided, generating a high-resolution picture of habitat use across seasons.

The results revealed that cattle did not use the landscape evenly. Instead, grazing and movement was clustered in specific habitat types while large portions of the pasture, particularly dense brush and shrub-dominated areas favorable to tick survival, remained consistently underused. Seasonal heat stress further amplified this pattern, shifting cattle away from certain habitats for prolonged periods.

These underused areas represent more than idle land. From a tick’s perspective, they are zones where pesticide exposure is low or nonexistent. Even when cattle on the ranch are treated, ticks located in places cattle rarely enter might escape control entirely.

By overlaying GPS movement data with geographic information system (GIS) habitat classifications, researchers were able to spatially define where these behavioral gaps occurred, effectively mapping where cattle presence, and therefore tick control pressure, was weakest.

The Role of Cattle Behavior Models for Predicting Tick Persistence

In the second study , researchers moved from observation to prediction. Using the acquired GPS-derived habitat use data, they built a specially explicit, individual based simulation model to explore how tick populations respond to different host and treatment scenarios.

Unlike traditional models that assume uniform host movement, this framework explicitly incorporates cattle behavior, including their avoidance of specific habitat types, alongside tick life history, habitat suitability and the presence of wildlife hosts, such as white-tailed deer and nilgai.

The simulations tested multiple scenarios: cattle-only systems, mixed wildlife-cattle systems, different pesticide treatment strategies and varying habitat use patterns. Across scenarios, a consistent result emerged. When cattle alone were treated, the standard eradication approach, tick populations frequently persisted in landscapes where cattle avoided substantial portions of tick-suitable habitat.

These persistence zones functioned as refugia: small but stable patches where ticks could survive, reproduce and later recolonize treatment areas. Importantly, the model showed eradication success was strongly influenced not just by those species, but by where hosts traveled across the landscape. Assuming homogeneous grazing behavior significantly overestimated the likelihood of tick elimination.

Why Cattle-Only Tick Control Fails: The Impact of Wildlife and Refugia

The presence of wildlife further compounded the problem. In simulated landscapes shared with deer or nilgai, ticks could cycle through hosts that moved freely through refugia, bypassing treating cattle altogether. Even low densities of wildlife were sufficient to sustain tick populations in favorable habitat patches, especially when cattle presence was inconsistent.

The modeling suggests eradication efforts falter not because ticks are ubiquitous, but because they are spatially selective. They exploit ecological and behavioral gaps. These gaps persist unless control strategies account for where cattle do not go.

Crucially, this research showed changes in grazing behavior, such as increasing cattle access to underused habitats, could substantially reduce tick persistence in simulation. Likewise, scenarios that incorporated treatment or management of wildlife hosts dramatically improved eradication outcomes.

A Spatial Approach to Tick Eradication

Together, the two studies argue for a reframing of tick eradication as a spatial and behavioral challenge rather than a purely chemical one. The failure to eliminate cattle fever ticks in Texas might stem less from insufficient treatment and more from incomplete coverage driven by cattle movement patterns.

This insight has immediate implications. Mapping cattle behavior using GPS data allows managers to identify where control pressure is weakest and to target interventions accordingly. This could be through adjusted grazing plans, focused surveillance, habitat modification or strategic wildlife management.

It all underscores the value of location intelligence in veterinary epidemiology. By integrating GPS tracking, GIS habitat data and individual based modeling, researchers can move beyond reactive control toward predictive, landscape-level strategies that anticipate where persistence is most likely. This reframes eradication not as a question of how much treatment is applied but of whether interventions reach the places cattle do not.

A Deworming Plan that Delivers

Wed, 10 Sep 2025 18:38:02 GMT

For Oklahoma producer Buck Rich and his veterinarian, Dr. Tyler Thomas, parasite control isn’t about doing more. It’s about doing it better.

Together, they’ve fine-tuned a simple, practical approach to parasite control that helps Rich’s herd stay healthy and productive all year long. Their success comes down to four practices that any producer can adopt: diagnostics, combination treatment, refugia and management.

Oklahoma producer Buck Rich (left) and veterinarian Dr. Tyler Thomas, owner of Prague Veterinary Clinic.

(Boehringer Ingelheim Animal Health USA Inc.)

Diagnostics: Start With the Facts

When Rich notices cattle underperforming, his first move isn’t to reach for more product — it’s to collect a fecal sample.

“You don’t know where to go until you know where you’re at,” explains Thomas, a mixed animal practitioner and owner of Prague Veterinary Clinic in Prague, Okla. “Diagnostics tell us if treatment is even necessary, and whether what we’ve done is working.”

Rich’s operation, Leaning Oak Ranch in Okemah, Okla., includes 2,000 pairs. Like many cow-calf operations, it’s heavily forage-based and parasite control plays a key role in performance.

“We had a group of cows that didn’t look right, and I assumed it was a worm issue,” Rich says. “But fecals came back clean. Diagnostics saved us from reworking the cows unnecessarily.”

That kind of clarity is why conducting fecal egg counts, before and after deworming, is a regular part of their plan.

“Without diagnostics, it’s easy to point the finger at the product,” adds Dr. Jody Wade, DVM, Boehringer Ingelheim. “But if you’re not testing, you might be treating the wrong issue or not seeing the whole picture.”

Combination Treatment: Target Parasites in Different Ways

Combination treatment is the practice of deworming cattle by using two or more dewormers from different drug classes. Dewormers can be divided into three different classes, based on their chemical structure and mechanism of action: macrocyclic lactones (endectocides), benzimidazoles (white dewormers) and imidazothiazoles. Each class controls a distinct spectrum of parasites, and for a different amount of time (see Figure 1).

For Rich and Thomas, implementing combination treatment was a game changer.

“We used to rotate products,” Rich recalls. “Now we use a white dewormer and a macrocyclic lactone at the same time. The cattle slick off faster and just look better.”

Figure 1: The three classes of dewormers.

(Boehringer Indelheim)

“Most operations already use a macrocyclic lactone,” Thomas explains. “Adding a white dewormer targets parasites differently. You get more coverage and it’s economical.”

Dr. Matt Washburn, DVM, Boehringer Ingelheim, says combination treatment is one of the most effective ways to slow resistance, while improving outcomes.

“Each class kills different parasites in different ways,” he points out. “When you use a combination of products, you clean up more effectively and reduce the risk of survivors.”

Refugia: Treat the Right Animals

It may go against tradition, but Rich and Thomas agree: Sometimes, the best choice is to skip the deworming treatment. This practice, known as refugia, leaves a portion of the herd untreated to maintain a population of susceptible parasites, helping dilute resistance across the herd.

“We’re wired to treat everything,” Rich says. “But when we’ve held back a few, like Dr. Thomas recommends, it’s worked, and we’re not wasting product.”

Wade notes that skipping treatment isn’t about doing less; it’s about doing what’s right.

“The days of treating everything, every time, are behind us,” he emphasizes. “Refugia takes discipline, but it gives us longevity. It protects the products we have.”

Buck Rich (left) and Dr. Tyler Thomas processing cattle.

(Boehringer Ingelheim)

Management: Strong Grazing Supports Stronger Control

Rich is quick to explain that success doesn’t just come from products; it’s also about how grazing is managed.

“We’re not extreme rotators, but we do move cattle regularly,” he says. “We try to leave about half the grass behind each time. It helps the pasture bounce back faster, and keeps parasite pressure lower.”

Thomas adds that forage height matters.

“Most infective larvae live in the bottom two inches of pasture,” he says. “If cattle graze above that, they’re exposed to fewer parasites. And it’s better for regrowth and soil health, too.”

Washburn agrees and adds, “Overgrazing doesn’t just hurt your grass. It increases parasite exposure and slows pasture recovery. Management is a pillar of deworming, just as much as the product in your chute.”

Planning that Pays

For Rich and Thomas, deworming isn’t a stand-alone decision; It’s part of a year-round plan. And that plan flexes with the season, the weather and the cattle in front of them.

“Herd health protocols aren’t static,” Thomas says. “If Buck’s going to keep calves for 10 months, we make a different plan than if they’re leaving in 60 days. It’s about making the product fit the goal, not the other way around.”

Rich’s partnership with Thomas helps him stay ahead of parasite pressure, while reducing unnecessary costs.

“I know I can call Dr. Thomas any time,” Rich stresses. “He understands our operation and helps me make decisions that actually fit what we’re doing. Working with my vet makes all the difference.”

That tailored approach is one reason Leaning Oak Ranch continues to see results year after year.

“It’s about using the tools we have wisely,” Washburn says. “When you put diagnostics, combination treatment, refugia and management together, you’re building something more sustainable — and profitable.”

For Rich, the proof is in the cattle and the next generation.

“This is a family operation. My kids are growing up on this ranch,” he concludes. “I want our cattle to look good now, but I also want this to work 10, 20 years from now. That’s why we do it this way.”

To explore strategies like the ones Rich and Thomas use visit DewormingLegends.com .

Rust in the Ration: How to Combat Southern Rust’s Impact on Corn Silage

Thu, 04 Sep 2025 14:04:47 GMT

With the warm and wet conditions this season, southern rust is on the rise in Midwest corn crops. It may be time to start considering the impact that could have on corn silage and preparing to adjust rations accordingly. While southern rust is not a direct threat to herd health, it has been shown to lower the nutritional value of silage and can compromise feed quality.

Southern rust, a fast-developing fungal disease caused by Puccinia polysora, does not itself produce toxins, but it weakens the plant and provides the opportunity for other diseases to move in. These opportunists include various Furasium species, which produce mycotoxins (fumonisin and deoxynivalenol) that can be harmful in feed.

Southern Rust and Corn Silage Quality

Southern rust is known to impact corn silage quality. A study from the University of Florida showed increasing rust infestation resulted in increased dry matter and fiber fractions, but that dry matter digestibility decreased by 13%. Further, high rust silages had lower neutral detergent fiber digestibilities than medium and no rust silages. Southern rust also affected the concentrations of lactate and volatile fatty acids, causing both to decrease with increasing infestation. These results indicate decreased nutritive value.

The observed increased dry matter also reduced silo packing effectiveness. If moisture levels are too low at harvest, it is difficult to achieve adequate packing, which leads to poor fermentation and an increased risk of mold growth.

Because southern rust coverage reduces the photosynthetic area of the leaf, grain fill is often hindered, leading to a lower energy and protein content in the silage.

Southern Rust Silage Management

There are a handful of strategies producers can apply to counteract the effects of southern rust:

Adjust harvest time based on moisture content. Southern rust can cause corn to dry down faster than normal. Monitor moisture levels closely to ensure the proper fermentation of silage.
Consider a silage inoculant. Inoculants improve fermentation, and the rapid pH drop can inhibit mold and yeast growth.
Ensure good packing and storage. Pack silage well to limit oxygen exposure and prevent mold growth. Cover bunkers immediately and weigh down coverings thoroughly.

Feeding Southern Rust Silage

To counter the nutritional challenges of feeding southern rust-infected corn silage, dietary supplementation may be necessary.

Prior to inclusion, test all potentially infected silage for mycotoxins. This will allow you to determine the safety of the feed and avoid potential health issues. If mycotoxins are high, the incorporation of a mycotoxin binding agent into the ration will help reduce toxin absorption in the animal’s digestive tract. Additionally, supplementation with antioxidants, such as vitamin E and selenium, could help animals by countering oxidative stress caused by mycotoxins and supporting immune function.

If grain fill was affected and starch levels are low, you may need to incorporate an additional energy course to compensate. Further, poor grain fill could reduce the already low protein content of corn silage, and protein supplementation may be required.

When incorporating infected silage, ensure it is thoroughly mixed into the TMR to dilute potential ‘hot spots’. Inclusion levels of contaminated silage in the feed may need to be limited or removed entirely for sensitive animals, including lactating or breeding animals. Livestock should be monitored closely for symptoms of mycotoxin toxicity, such as reduced intake, weight loss, digestive issues or reproductive challenges. Be prepared to respond if issues arise.

When feeding corn silage infected with southern rust, caution is essential to protect livestock health and performance. The thoughtful use of compromised silage can help minimize risk while maintaining efficiency and animal well-being.

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Theileria and the Asian Longhorned Tick: What Beef Producers Need to Know

Wed, 06 Aug 2025 16:56:39 GMT

The Asian longhorned tick (ALHT) poses a serious threat to cattle health. ALHTs carry Theileria, which is a protozoan parasite that infects red and white blood cells. It can lead to anemia and, in some cases, death.

In the U.S., ALHT was first detected in New Jersey in 2017. Since then, it has spread to more than 20 states. With the recent discovery of ALHT in southeast Iowa , the Iowa Cattlemen’s Association hosted a webinar lead by Cassandra Olds, Kansas State University Extension entomologist, who explained the tick and pathogen background, its potential impacts, best practices for prevention, as well as caring and treatment strategies.

“This was always a when, not an if,” Olds explains. “You did absolutely nothing wrong. If you have the tick or the pathogen, this was an inevitable thing.”

What We Know about ALHT and Theileria

Biologically, the ALHT is a three-host tick, meaning each life stage — larva, nymph and adult — feeds on a different host. Olds says unlike other tick species, it can reproduce asexually, with all adult ticks being females capable of laying eggs without mating. This characteristic allows for rapid population growth, as a single tick can potentially establish an entire population.

Once an animal is infected with Theileria, it becomes a chronic carrier for life, with the potential to relapse during high-stress periods. The pathogen replicates in red blood cells, causing anemia and a range of symptoms including loss of appetite, weight loss, fever and respiratory issues.

Olds says while the first year of exposure can be challenging, long-term production impacts are typically minimal. The key is to approach the situation with knowledge, preparedness and a calm, strategic mindset.

She stresses that just because a cow herd does not have the symptoms doesn’t mean it doesn’t have Theileria. It just means that if an animal was infected, it didn’t develop the disease.

She reports mortality rates due to Theileria range from 5% to 20%. With the highest mortality when pathogen is first introduced — the outbreak. An animal can have a relapse of disease, often during high stress or immune compromising events.

She explains the high-risk animals are young (under 6 months), pregnant animals, stressed animals and any naïve animal moving into an area with previous outbreaks.

Best Practices for Prevention

Olds notes the pathogen can spread through tick bites and through shared veterinary needles. She says her team is currently researching the role of biting flies in transmission.

She stresses the importance of maintaining animal health and reducing stress to prevent disease outbreaks.

“Keep animals happy and healthy. Stress does weird things to immune responses,” she adds.

According to Olds these strategies can help control AHLT:

Burning pastures
Keeping grass short
Careful use of insecticides
Pasture rotation
Ear tags and pour-ons

(Data: Oklahoma State University; Tick Photo: J.A. Cammack)

Real-World Experience

Veterinarians John Currin and Austin Williams share their firsthand experiences with ALHT and Theileria.

Currin serves as associate professor and production management medicine with the VA-MD College of Veterinary Medicine at Virginia Tech. He says in his area more than 90% of the herds are infected and many don’t know they’re infected.

“The tick epidemiology is — I’ll use a scientific term — weird,” he says.

He explains as the disease became endemic in Virginia, its clinical presentation changed. While it initially affected adult pregnant cows, it now more commonly impacts 2-month-old calves in spring calving herds.

“There is no in utero spread of this organism, so every calf starts naïve,” Currin says.

Approximately 80% of calves in infected herds become positive by 3 months of age, though most do not show severe clinical signs.

He adds contrary to initial concerns the Theileria appears to have minimal impact on cattle in a feedlot. Currin says research found no significant differences in weight gain between negative and positive cattle.

He stresses the primary concern is for cow-calf operations bringing naive animals into infected areas.

Currin shares these key points about Theileria:

99% of herds will experience minimal problems
Most infected animals show no significant clinical signs
The disease primarily causes anemia
There’s no direct treatment available
Positive tests are now almost meaningless in endemic areas

Williams serves producers in northwest Arkansas and southwest Missouri.

“I think it’s been here longer than we recognize and it’s more widespread than what we realize it too,” he says. “I would say some states have it that don’t know they have it.”

In Williams’ area he has seen the tick infestation become widespread. The key challenges he’s witnessed is the difficulty of managing the tick population and the potential for secondary health issues in infected cattle.

He recommends individual herd management strategies, including regular checks, treatment plans and potentially moving infected herds to different pastures.

Treatment Strategies

There are currently no labeled treatments for the disease or a definitive cure. Typically, treatment focuses on secondary issues and providing basic care.

Avoid mass injecting ivermectin, as it can cause resistance and harm beneficial insects like dung beetles.

“Please don’t just mass inject everybody with ivermectin because you’re worried about the Asian longhorned tick,” Olds says.

Vaccine Developed

Medgene has developed a tick vaccine that is designed to work on multiple tick species, including ALHT. Veterinarians can purchase directly from Medgene. The vaccine requires two initial doses, followed by yearly booster shots.

Williams says he’s had clients use the vaccine this year, and he’s hopeful about the vaccine’s potential and is waiting for more research from the University of Arkansas to provide concrete data on its effectiveness.

Gary Bosch, Medgene executive vice president, says animals should be vaccinated before they encounter ticks.

“In the Southern U.S. where ticks are a year-round problem, early vaccination is especially crucial because the Asian longhorned tick can overwhelm an animal very quickly,” he says.

Industry Impacts

Olds says the goal is to achieve “endemic stability” — when most animals are exposed early and develop lifelong immunity with minimal disease symptoms.

She emphasizes the need to remove the stigma associated with the tick or pathogen presence, noting that infection is an inevitable part of agricultural reality. Producers should focus on proactive testing, management and community support.

To prepare for and to deal with Theileria, Olds recommends producers:

Establish a good relationship with a veterinarian
Conduct regular herd testing
Maintain low-stress environments
Implement careful tick control measures
Share information and support each other as a community

Her final advice is to be vigilant but not panicked.

“Producers should view the Asian longhorned tick as a manageable challenge rather than a catastrophic threat,” she summarizes. “By working together, maintaining animal health and implementing smart management strategies, the agricultural community can effectively navigate this emerging issue.”

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Heat Stress in Cattle Costs Real Money

Mon, 14 Jul 2025 17:10:18 GMT

Cattle rid their bodies of heat in three ways — radiation, convection and evaporation.

“If your cattle can’t use all three methods, they’ll overheat fast,” says Eric Bailey, University of Missouri Extension state beef nutrition specialist.

Summer heat knocks weight off calves and pounds off milk, Bailey says. Losses come in the form of less gain, weaker fertility and other health issues.

“Heat stress costs real money,” he says.

Producers can reduce heat stress by providing adequate shade, proper fly control, access to water and the right choice of pasture grass.

Tall Fescue Pastures Turn Up the Heat

Cattle grazing on tall fescue grass when temperatures rise is a recipe for disaster.

Toxic endophytes in fescue can turn up the cattle’s body heat. Their efforts to keep cool can melt profits. But there are practical fixes that keep weight and profits steady, Bailey says.

Most fescue pastures in the Fescue Belt carry endophytes that make toxic ergot alkaloids, which mess with your cattle’s ability to stay cool, he says.

These toxins tighten blood vessels, cut blood flow to the skin and prevent heat from escaping. They make it hard for cattle to sweat and pant, essential tasks to rid their bodies of heat. Third, ergot alkaloids delay shedding by lowering prolactin. This leaves cattle with shaggy coats that trap summer heat.

Summer temperatures, especially heat waves, make cattle on fescue vulnerable to problems. Normally, cattle can tolerate temperatures of 31 C or 88 F. Cows likely consume enough ergovaline by Memorial Day to make heat stress worse during the summer.

Small Amounts Cause Big Losses

Even ingesting small amounts of ergot alkaloids can result in reduced weight gain and smaller calves, less milk, lower fertility and lighter wallets, says Bailey. He offers these suggestions on avoiding losses from heat stress:

Rotate toxic tall fescues with other grasses such as clover, or interseed pastures with nontoxic novel-endophyte fescue to dilute.
Consider investing in full pasture renovation on the worst fields. See the Alliance for Grassland Renewal website for information on renovating tall fescue pastures.
Provide supplemental feed in the range of 0.5% to 1.0% of bodyweight per day to dilute ergovaline in the diet.

Maintain Good Fly control

If you have cows on tall fescue, pay special attention to fly control .

“If your cattle are on toxic tall fescue and they are crowding together to dodge flies, the deck is stacked against them,” Bailey says.

Cattle tend to bunch up to avoid flies, especially stable flies that attack their legs. They congregate in the middle of the pasture and avoid the field edges where flies gather most.

Bunching traps heat, cuts radiation and convection in half, and raises humidity significantly. “In severe cases, cows quit radiating heat and actually begin to heat up even in the shade,” Bailey says.

Here’s the fix:

Drag pastures to break up manure, which is a breeding ground for flies.
Use fly tags, traps or parasitic wasps to cut fly numbers.
Finally, rotate pastures to break fly life cycles.

Give your herd shade

Bailey gives guidelines to discourage bunching and encourage cattle to space out in pastures:

Provide 20-30 square feet of shade per cow.
Provide portable shade structures that allow airflow.
Place water troughs 50-100 feet apart to encourage animals to spread out.

Finally, radiation and convection need cool surroundings and airflow to work, says Bailey.

“They fail when it’s hot and crowded. Evaporation is the last line of defense in a heat wave, but humidity and fescue toxins can cripple it,” he says.

For more information, see the MU Extension publication “Tall Fescue Toxicosis” (G4669) .

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Open Heifers Explained: What You Need to Consider to Increase Preg Rates

Mon, 30 Jun 2025 21:09:29 GMT

A producer has a group of 112 heifers. The heifers were synchronized, and after a 45-day breeding season only 80% were confirmed pregnant.

During a recent “ Bovine Science with BCI ” podcast, Kansas State University veterinarians Brad White and Bob Larson explore potential causes for the issue — from bull problems to nutritional and health-related factors. They also share practical strategies and management tips producers can implement to improve reproductive success and set the herd up for a better breeding season.

Larson says, while the pregnancy rates weren’t optimal, the results weren’t catastrophic. The first breeding cycle performed well.

Reviewing the pregnancy data they determined:

57% of heifers became pregnant in the first 21-day breeding cycle.
After synchronization the heifers were artificially inseminated and then turned out with bulls. Larson says the goal or expectation should be 60% to 65% every 21 days so 57% is not too low.
39% of remaining heifers got pregnant in the second 21-day cycle.
Larson explains this is the rate that is the biggest problem and concern.
The final breeding period (about four days) added a few more pregnancies.

White explains about those who conceived in the first cycle, “Those heifers kept out of this scenario are going to be great cows for the herd. They’re bred at the right time.”

According to the veterinarians the potential reasons for the less-than-ideal pregnancy rates after the first cycle include:

Heifer Factors
Heifers were initially developed in a dry lot with a high body condition score (7 out of 9) then moved from dry lot to native range after initial breeding. Larson says the potential body condition loss could have impacted fertility as a negative energy pattern can pause a female’s estrus cycle.
Bull Factors
The producer turned out the 112 heifers with five bulls — three yearlings and two mature bulls. With the conception after the first cycle, the bulls had approximately 48 heifers to service. Larson explains the biggest concern is the synchronization created a concentrated breeding period and the bulls might have struggled with multiple heifers in heat simultaneously. Another fertility consideration is social dynamics and breeding behavior.
“The only solution I have for that is more bull power,” Larson says. “And that can get expensive, really fast, when you think about dollars per pregnancy during that second 21 days, when you know 60% of them are already pregnant.”

After reviewing the case, Larson gave these recommendations to the producer:

Target and maintain heifer body condition score around 6 (not 7)
Avoid significant body condition changes during early pregnancy
Carefully time movement from dry lot to pasture
Consider smaller heifer groups
Potentially rotate bulls between groups
Explore heat detection and re-breeding options
Evaluate bull power and allocation strategies

The discussion highlights the complexity of heifer breeding, emphasizing that multiple factors can influence pregnancy rates. Larson summarizes careful observation, strategic management and understanding the biological and social dynamics of the herd are crucial to improve reproductive success.

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Beef Producers Be Aware: Dangerous Asian Longhorned Tick Continues Migrating West

Wed, 18 Jun 2025 13:24:33 GMT

The Asian Longhorned Tick (ALHT) poses a serious threat to cattle health. ALHTs carry Theileria, which is a protozoan parasite that infects red and white blood cells. It can lead to anemia and, in some cases, death.

ALHTs are native to eastern Asia, eastern China, Japan, the Russian Far East and Korea but were introduced to Australia, New Zealand and western Pacific Islands. In other countries, it can also be called a bush tick, cattle tick or scrub tick.

In the U.S., ALHT was first detected in New Jersey in 2017. Since then, it has spread to more than 20 states with recent confirmations in Illinois , Michigan and Iowa .

According to USDA’s Animal and Plant Health Inspection Service (APHIS) ALHTs are known to carry pathogens, which can cause disease and may also cause distress to the host from their feeding in large numbers. For example, a dairy cow may have a 25% decrease in milk production after becoming a host.

A female can reproduce without a mate and lay up to 2,000 eggs at a time. This can cause great stress on a heavily infested animal and result in reduced growth and production. A severe infestation can kill the animal from excessive blood loss.

Asian longhorned tick life stages and relative actual size.

(Photos of unfed ticks by Centers for Disease Control. Photos of engorged ticks by Jim Occi, Rutgers, Center for Vector Biology.)

What does it look like?

Unfed ALHTs range from a light reddish-tan to a dark red with brown, dark markings. While the adult female grows to the size of a pea when full of blood, other stages of the tick are very small — about the size of a sesame seed.

Adult females are a grey-green with yellowish markings. Male ticks are rare.

APHIS reports it only takes a single tick to create a population in a new location.

The above photos are of a AHLT engorged (on the left) and an adult AHLT not engorged.

(New Jersey Department of Agriculture)

ALHTs need warm-blooded hosts to feed and survive. They have been found on various species of domestic animals — such as sheep, goats, dogs, cats, horses, cattle and chickens — and wildlife. The tick has also been found on people.

What are the health risks?

APHIS says ALHTs are not known to carry Lyme disease, but they can cause tickborne diseases affecting humans and animals such as:

Rocky Mountain spotted fever
Heartland virus
Powassan virus

APHIS says those diseases have not been confirmed outside of a laboratory setting in the U.S. In addition, U.S. ALHT populations can transmit U.S. Theileria orientalis Ikeda strain (Cattle theileriosis) in the laboratory.

In an Iowa State University release , Grant Dewell, Extension beef veterinarian and associate professor, says cattle affected by Theileriosis will show signs of lethargy, anemia and difficulty breathing. They may develop ventral edema, exercise intolerance, jaundice and abortions.

“Although signs of Theileriosis are similar to anaplasmosis, younger animals and calves often display more severe signs compared to mature cows and bulls,” he says. “Due to anemia from both tick infestation and Theileria, the risk of death can be elevated. If cattle producers suspect either Theileria or ALHT, have a veterinarian collect appropriate samples and submit them to a veterinary diagnostic lab.”

According to an Oklahoma State University press release , under laboratory conditions ALHT is a competent vector of numerous pathogens that can cause disease in humans, including Rickettsia rickettsii (Rocky Mountain Spotted Fever), Heartland Virus and Powassan Virus.

In “ Clinical Infectious Diseases, ” Bobbi Pritt, MD, MSC, with the division of clinical microbiology at the Mayo Clinic in Rochester, Minn., reported a human bite that occurred in New York in 2019. She says though the report of a human bite isn’t surprising, it proves the invasive longhorned tick continues to bite hosts in its newest location.

“This is extremely worrisome for several reasons,” she writes. “One reason is Asian longhorned ticks can carry several important human pathogens, including the potentially fatal severe fever with thrombocytopenia syndrome (SFTS) virus and Rickettsia japonica, which cases Japanese spotted fever. While these pathogens have yet to be found in the United States, there is a risk of their future introduction.”

Also, Pritt says several other human pathogens have been detected in the ticks, but it’s not clear if the ALHT species are able to transmit them to humans. They include Anaplasma, Ehrlichia, Rickettsia, and Borrelia species. Lyme disease is caused by Borrelia burgdorferi bacteria.

She warns the organisms are present in states where ALHTs have been found and that it’s possible the tick — known to be an aggressive biter— might be able to transmit Heartland virus given its close relationship to SFTS virus.

How to Tackle Ticks

According to APHIS, various strategies effectively mitigate tick populations on hosts and in the environment.

Regular tick treatments should be effective against ALHTs. Consult your veterinarian or agriculture extension agent about which products to use.
Check your livestock for ticks regularly.
Safely remove ticks from people and pets as quickly as possible. If you think you’ve found an ALHT, seal it in a zip-top bag and give it to your veterinarian for identification.
Habitat modifications can help prevent ticks on feedlots and pastures. This may include mowing grass, removing trees, reducing shade by thinning trees, understory removal and placing mulch barriers.
Apply acaricide using label instructions to tick habitats, such as woodland edges and grassy patches, during times when ticks are most actively seeking hosts. Although it varies by year, ALHTs are generally active from March to November. Consult your state and local regulations for approved acaricides.

“Cattle producers should aggressively control external parasites this summer,” Dewell summarizes. “Insecticide ear tags alone are not enough to control ticks. Consider incorporating a back rubber or regularly applying a pour-on during the summer. Pyrethroid-based products are also available that include a tick control label. If an increase in tick infestations is observed, an avermectin pour-on may be the best intervention.”

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Protect Your Herd: Essential Tips for Preventing Pinkeye Post Pasture Turnout

Tue, 27 May 2025 12:07:54 GMT

As herds are being turned out on pasture, most calves will get an immunity boost for select diseases through a vaccination program.

“Arguably the most common health nuisance on pasture — pinkeye — doesn’t have an easy vaccine solution with consistent efficacy,” says Chris Clark, Iowa State University extension beef specialist. “In part, this is because pinkeye is complicated, involving multiple bacterial strains and risk factors.”

The solution? Prevention, prevention and early intervention.

Prevention Points

Reduce corneal irritants. The cornea provides a protective layer over the eye, and when it is healthy, bacteria cannot attach. Irritants that damage the cornea allow bacteria to colonize and infection to occur. Common irritants on pasture include UV light, seedheads and dust.
Control fly populations. Flies contribute to cornea irritation, but the primary role of flies in regard to pinkeye is carrying the bacteria from one animal to the next, and facilitating transmission. Because flies can travel distances, the adage “your fly control program is only as good as your neighbor’s” bears truth. But by taking steps in your herd, populations can still be significantly reduced. Multifaceted approaches are the most effective.
Prioritize nutrition. Multiple macronutrients and micronutrients are essential for an effective immune response. A well-balanced mineral program is important in keeping the herd healthy. Mineral supplements can become costly, so a solid understanding of mineral levels in the available feed and water can help reduce some costs without sacrificing animal performance.

Early Intervention

Check cattle regularly and watch closely for early signs of infection. Once clinical signs are observed, initiate treatment as soon as possible to minimize complications and severe cases.
Treat with systemic antibiotics labeled for pinkeye and be diligent in following label directions. Weigh animals to ensure appropriate dosing. Use good injection site practices to ensure optimal drug absorption.
Adjunct therapy such as eye patches, stitching eyelids shut and subconjunctival injections are sometimes used in addition to systemic antibiotics. Evidence is somewhat inconsistent regarding efficacy of these practices. Eye patches have been shown to speed corneal ulcer healing, but for best results, leave a spot open to facilitate drainage and airflow when applying. Pinkeye increases sensitivity to UV light, so shade can be helpful for animal comfort. Pain associated with pinkeye may warrant the use of an anti-inflammatory as well. Topical ointments and sprays are also sometimes used.

“As with all health challenges, work closely with your veterinarian to develop a plan for dealing with cases,” Clark says. “Before using any medications, talk with your veterinarian about safety and legality for use in the eye, required dosing schedules and required withdrawal times.”

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Spring Pastures Alert: Be Aware of Frothy Bloat Risk

Tue, 20 May 2025 15:10:22 GMT

Death losses from pasture bloat are estimated to be approximately 2% annually but are sometimes much higher (10% to 20%) on individual pastures.

“Costs of bloat include not only losses of livestock but also decreased productivity from avoidance of the most nutritious pastures due to bloat risk,” says Michelle Arnold, DVM and University of Kentucky ruminant extension veterinarian. “Bloat incidence varies year-to-year depending on the relative presence or absence of clover; years with low residual grass cover in the fall, especially after fall drought, and sufficient moisture in the spring will favor clover dominance.”

Frothy bloat occurs when cattle graze forages high in soluble protein and low in fiber, most commonly pastures with a high percentage of immature legumes (alfalfa, white clover) or succulent, vegetative wheat or rye pastures.

“This disorder is caused by the interaction of many factors including environmental conditions, the structural and chemical composition of the forages present, and physiologic factors within the animal,” Arnold explains.

Because it is multifactorial, frothy bloat occurrence is sporadic, unpredictable and difficult to completely prevent. It is most reported when cattle, especially yearlings, graze legume or legume-based pastures (over 50% legumes) in the late winter and early spring.

What is Bloat?

Ruminant animals produce large volumes of gas through the normal fermentation process during forage digestion. This gas is predominantly belched (eructated) or it passes through the gastrointestinal tract. If something interferes with gas escape from the rumen, pressure builds up and causes an obvious distension in the left flank of the abdomen, a condition known as bloat.

The swollen rumen occupies a large amount of space within the abdomen resulting in compression of the lungs and diaphragm, which interferes with breathing and tissue oxygenation, obstruction of blood flow to vital organs and potentially the rapid death of the animal. Bloat may be classified into one of two types — free gas or frothy — with both possible in cattle whether on pasture or in a confinement feedlot setting.

Free gas bloat in pastured cattle is most often due to obstruction of the esophagus (choke) with rapid onset of bloat and death if not addressed quickly. Free gas bloat from choke can be relieved by passing a tube down the esophagus into the rumen, simultaneously clearing the esophageal obstruction and releasing the trapped gas.

Frothy bloat, on the other hand, results when fermentation gases become trapped within a stable foam in the rumen (like the head of a beer) and the animal is no longer able to belch up the gas. Simply passing a tube into the rumen will not solve the problem, because the froth prevents gas from leaving the pressurized rumen. For effective relief, anti-foaming agents must be delivered directly into the rumen to disperse the foam and allow the gases to escape.

Frothy Bloat Characteristics

Frothy bloat results when fermentation gases become trapped in a stable foam in the rumen that cannot be released by eructation. Requirements for this foam to form are:

Consumption of a highly digestible, high-protein forage (such as alfalfa, white clover, wheat) that results in rapid gas production, promotes the growth of ruminal microbial populations and increases rumen fluid viscosity.
The presence of fine plant particles (from ruptured chloroplasts) that cause gas bubbles to coalesce in rumen contents.
Active ruminal bacterial production of an excessive amount of bacterial “slime” (a mucopolysaccharide complex also known as a biofilm).

“The incidence of bloat is variable between animals and depends on the individual animal’s rate of forage fermentation and production of ruminal gas, the digesta passage rate and the foaming properties of rumen contents,” Arnold says.

For example, a slower passage rate allows more time for foam formation and a higher chance of bloat. Similarly, the abundance of certain salivary proteins within saliva decreases that animal’s formation of rumen foam.

“Some animals have a genetic predisposition to bloat, and chronic bloaters should be culled,” Arnold says.

Signs of Bloat

According to Arnold, the signs of bloat are easily recognized if observed; the problem is an animal may go from normal to dead within an hour.

Cattle with early bloat display a distended left flank, and they stop grazing, may kick at their belly and be reluctant to move.

As bloat advances, the animal may appear distressed (may vocalize, eyes may bulge), stand up and lie down repeatedly, strain to urinate and defecate, exhibit rapid and open mouth breathing, grunting, staggering and, in advanced cases, the animal will go down.

“Death is rapid at this stage due to compression of the lungs, diaphragm and major organs by the distended rumen,” Arnold says. “Animals that are mildly affected can be drenched orally or through a stomach tube with a liquid anti-bloat preparation containing the surfactant poloxalene. After dosing, it is encouraged to keep the animal moving to allow the preparation to mix with the frothy rumen contents.”

Severely bloated animals in distress need immediate veterinary attention. Arnold says this may be achieved by inserting a wide bore trocar and cannula into the rumen at the highest point on the left flank (where the swelling is greatest).

“After gas and froth is released, an anti-bloat preparation can be poured through the cannula into the rumen to help break down all remaining froth/foam,” she explains. “If poloxalene is unavailable, vegetable oil (250-500 mL) or mineral oil (100-200 mL) can be used.”

In most cases of advanced frothy bloat, a trocar and cannula will quickly plug up with foam and will not be adequate to relieve the pressure.

“In those cases, a 10-to-20-cm incision will have to be made using a scalpel or clean, sharp knife inserted into the highest point of the left flank,” Arnold says. “It may be necessary to manually remove the frothy material from the rumen. In these emergency cases there is usually no time to wait for a vet to arrive, so livestock owners will have to do this themselves. Veterinary attention is still necessary to irrigate the abdominal cavity, clean and stitch the wound and begin antibiotic treatment to prevent serious infection.”

Prevention Tips

Arnold shares these tips to help prevent frothy bloat:

Avoid grazing cattle on lush, rapidly growing, immature legume or wheat pastures. “This is exceptionally important if the forage is wet from dew or rain,” she says. “Moisture plays a role in a forage’s bloat potential. Hungry cattle graze more aggressively when moved to a new pasture, so they should not be moved to new pastures with high legume content until midday — after the dew has dried and after they have grazed or consumed hay in the morning.”
Watch cattle closely for the first few days on new pasture. “Bloat onset may be observed within an hour after introduction to new pasture, but cattle more commonly bloat on the second or third day following introduction,” she says. “Observe animals closely following any abrupt change in the weather.”
Slow the movement of cattle to new paddocks when practicing rotational grazing to offer cattle more mature forages in pastures.
Provide cattle with free-choice access to anti-bloat blocks or offer feed daily that is top-dressed or mixed with poloxalene.
Ensure cattle always have palatable grass hay available.
Provide additional calcium to growing cattle grazing wheat pasture. “Cereal grains are notoriously low in calcium; ruminal and gut motility is greatly compromised in animals with subclinical deficiencies of blood calcium,” she says.
Always provide a good trace-mineral mix to grazing cattle as high potassium and low sodium levels in the rumen are associated with bloat.
Provide access to a clean water source.
Long-term control is based on growing grass-legume mixtures and/or incorporating bloat-resistant legumes into pastures.

Your Next Read: Liver Flukes: Understanding and Effectively Managing the Parasite

Can We Graze the Same Number of Calves when Wheat Pasture is Limited?

Tue, 31 Dec 2024 12:57:22 GMT

The performance of growing calves on wheat pasture can by increased by providing a small amount of a concentrate supplement carrying an ionophore and minerals that are deficient in wheat pasture . In many areas of Oklahoma and the Southern Plains, wheat pasture this year has yielded much less than our normal expectations, but there are economic incentives to graze as many calves on pasture as possible this winter. Additionally, there are several options available to offset the reduced forage allowance of wheat pastures this winter and maintain expected gains of grazing calves.

Using a Self-Fed Supplement
Providing grains or byproduct feeds free-choice in a bulk feeder has historically been an option when feed is cheap. Even though there is risk in feeding free choice, providing whole corn or ground grain sorghum choice results in as fed intake of 1.5 to 2.0% of bodyweight with doubling of stocking rates. This resulted in increased performance but required 9 to 10 pounds of concentrate supplement per pound of added gain. Based on current prices of calves and futures prices on feeders, the calculated value of gain is conservatively around $1.20 per pound. For a self-fed concentrate supplement to break even, feed costs should be $241/ton or less ($6.75/bushel of corn) which may work if you have corn or other feed grains locally available.

Hand-Feeding at a Moderate Supplement Rate
Research from the OSU Wheat Pasture Research Unit at Marshall (Horn and others 1995, Journal of Animal Science Volume 73, https://doi.org/10.2527/1995.73145x) showed that providing a concentrate supplement (based on either corn or a soyhull/wheat middling blend) containing monensin at 0.65 to 0.75% of body weight (for example, 4 pounds per day for a 533-pound steer) increased potential stocking rate by 33% and weight gains by 0.3 pounds per day. The increased stocking rate and increase in performance of grazing calves is a powerful economic tool in managing wheat pasture, with supplemental efficiency of 5 pounds of supplement required per pound of added gain per acre.

This supplementation program can also be used to “stretch” wheat forage when pastures were 60 to 80% of normal, allowing for “normal” stocking rates. Recently researchers at OSU (McNeill and others, 2020, Journal of Animal Science, Volume 98) stocked steers on wheat pastures at forage allowances of either 1.5 or 3 pounds of forage DM/pound of steer bodyweight with or without 3.3 lbs. per day of a wheat middling/soyhull feed blend. Steers on the higher forage allowance (3.0 lbs forage DM/ lb steer bodyweight) with supplementation gained the most (3.8 lbs/day) while unsupplemented steers on the higher forage allowance gained 3.6 lbs/day. Supplementation increased gains more for steers at the lower forage allowance where gains of steers stocked at forage allowance of 1.5 lbs forage DM/lb steer bodyweight increased from 2.5 to 3.2 lbs/day with supplementation.

Using Good Quality Hay or Silage
Intake of low-quality roughages is not high enough to offset wheat forage intake and can reduce performance of growing calves, but in the 1980’s, research showed that offering high quality roughages such as corn silage or sorghum double stocking rates on wheat pastures. This research was repeated by offering bermudagrass round bale silage to steers stocked at 1, 1.5 or 2 steers per acre with forage allowances going from 2.9 to 1.2 lbs forage/lb of bodyweight (Beck and others, Applied Animal Science, 2023, Volume 40). Offering round bale silage at the lowest stocking rate actually increased gains compared with steers at the same stocking rate without silage (3.15 vs 2.79 lbs/day). As we increased stocking rate, average daily gain decreased, but total gain per acre increased by 52% when stocking rates were doubled. Based on this research, we should be able to maintain our normal stocking rates on wheat pasture during the fall and winter with adequate ADG by feeding moderate quality forages even if wheat forage production is 50% below our normal expectations.

There are some feeding options available to us when the economic conditions are right, but forage conditions are lacking. Feeding either limited concentrate supplementation or moderate quality roughage during the fall can increase production stability and thus improve economic stability of the wheat stocker enterprise.

Your next read: 2025 Ag Workplace Trends: What Employers are Saying

The Foundation of the Cattle Industry Is Grass

Thu, 21 Nov 2024 14:28:19 GMT

The last 90 days have been a definite reminder of how quickly conditions in the cattle industry can change and remind us that while record-high cattle prices can generate optimism for cattlemen, the outlook is still largely driven by grazing. While their financial well-being is a function of the market, it is also a function of the availability of grass. Both define the cattle cycle. Furthermore, grazing is critical for rangeland health.

For cattlemen losing a large share of their grazing capacity as the result of wildfires or drought, the rosiest outlook generated by record-high prices can quickly become one of uncertainty. Western states ranchers dependent on Federal lands grazing (BLM and Forest Service), will not just feel the impact of a season of severe wildfires in 2024, but beyond, as restoration of these rangelands could last a period of 4 to 5 years.

Obviously, that period does not include grazing. Record-high prices or otherwise, this is a significant challenge – to say the least. While there was an immediate need for grazing or hay to replace the loss, that loss of grazing capacity must be replaced over the longer term — 2025 and beyond — particularly if it represented a large share of the ranch’s total grazing. Furthermore, it has been expressed that Federal grazing on selected allotments could be sharply reduced or discontinued on selected allotments following the wildfires. I believe this to be a strong possibility.

Beyond the wildfires in the West, the industry is also faced with serious drought conditions across both the West and the Midwest. This situation ranges from a continuation of the problem in selected areas to one that is just beginning in other areas and these drought conditions are one factor leading to wildfires. There are cattlemen who have already liquidated part of their herd or their entire herd. For others, that decision may still be yet to come. The situation poses the same challenge as that of wildfires — replacing forage. The drought situation can still improve over the next several months with good winter and spring moisture conditions. That is not the situation on Federal grazing lands or private lands grazing where wildfire occurred. The cards have been laid on the table and range restoration will include spraying for weeds, seeding, and plant establishment.

I am expressing the conditions related to grazing capacity following this summer’s wildfires and the drought situation to really bring to the forefront the importance of grazing to the cattle industry and rangeland health and its impact on the outlook for the cattle numbers going forward. Record-high prices are certainly a crucial factor in the assessing the direction of the industry, but grass is still the priority for the individual cattleman and the outlook for the cattle inventory.

Balancing Quality and Cost When Feeding Your Cow Herd

Thu, 12 Sep 2024 15:42:40 GMT

Wouldn’t it be nice if we could graze 365 days out of the year? Think about the feed, fuel, time and overall money you would save! While it’s a great goal to aim for, it simply isn’t realistic for all climates or ranches. If you fall into the category of cattlemen and women who simply must supplement feed at some point during the year, understanding the quality of your feed and how to reduce feed waste is vital to your success each year. Dr. Karl Hoppe, Livestock Systems Specialist at the Carrington Research Extension Center, offers insight into how cattle producers can better understand the nutritional requirements of their cows and how to pair that with the quality of feed they have available during Season 7, Episode 35 of the Casual Cattle Conversations podcast.

Body condition scoring is a common method of evaluating if your cows’ nutritional needs are being met. To use this information effectively, ranchers must know how long it takes to move their cows up a score if they are thinner than desired.

“When it comes to winter feeding, you need to think six months ahead,” Hoppe says.

Depending on the cow, there is approximately a 80-pound difference from one body condition score to the next. How long it will take you to make that gain depends on the genetics of your herd and a variety of environmental factors one being feed quality. To set your herd up for optimal performance, you must know what they need for nutrients and what our feed sources have to offer.

“People often think if cows are thin, they can just throw a few extra bales out for them,” Hoppe says. “This happens during cold, wintry days too. But the cows need energy, not just extra feed. We tend to miss this and don’t realize how much energy our cows need.”

The solution is simple, test your hay each year.

As soon as your hay is put up, you can test it and get results back within a few days. It is encouraged to test for energy, protein, calcium, phosphorus and trace minerals. However, it can be beneficial to test for toxins such as nitrates which are more common during dry years.

When it comes to collecting samples, Karl says, “Make sure you get at least a quart bag full of corings for an adequate sample.”

Additionally, it is wise to test bales from each field because there can be large variances between different types of hay and the land it was grown on. For those who grind and mix different quality hay, test before you grind as the ground hay pile isn’t mixed enough to offer a representative sample. If you don’t have a probe to collect samples, reach out to your extension agent, feed store or feed company representative for help. If you need to test feed that is supposed to be ensiled, be sure to allow this process to take place before collecting samples. For distillers, ask the plant or location you are purchasing from if they have averages for quality so you can formulate an accurate ration. Feed and hay samples can be sent to commercial laboratories that run these tests often. The National Forage Testing Lab website is a good resource for cattle producers to find a lab near them.

Testing the feed is one thing. Raising high-quality, cost-effective feed is another. We tend to do a lot of things like generations before us, but our cows and economy are not the same. This makes it important to explore different options and be flexible with our environment and weather to raise cost-effective, high-quality feed. This might look like grazing or haying different feeds like rye, barley, winter wheat, sorghum-sudan mixes, oats, forage sorghum or corn silage. From an energy standpoint, corn silage is a great feed source to include in your total mixed ration (TMR), which can also be cost-effective. Your location may also provide access to different byproducts such as wheat middlings, soy hulls, beet pulp or corn gluten-feed just to name a few examples. Hoppe helps North Dakota producers incorporate these into their rations.

You can raise it. You can test it. How do you make sure you don’t waste it?

There are numerous strategies to reduce feed waste depending on what and how you are delivering this feed. For those feeding a TMR, feed bunks are the best option to reduce waste. For round bales, look at different feeders to help keep the hay in the feeder and not on the ground. Karl reminds producers, “Cattle don’t waste high quality hay. Cattle do waste poor quality hay.” So, take this into consideration when deciding how and what to feed your herd. There are opportunity costs to consider when deciding to feed a TMR or stick to bales. Hoppe said, “It costs money to grind hay, run two tractors and own a mixer wagon; so if you own a small amount of cows it might be cheaper to let cows waste a greater percentage of hay rather than feed a TMR. But, don’t forget to consider the cost of that hay that is now considered bedding. Your hay could be $100/ton which is expensive bedding compared to $40/ton straw or stover.” Before you get into the argument of which option is best for you, be sure to know your costs to get the most accurate picture.

As we work toward increasing our grazing days and decreasing our feeding days, remember there is no one-size-fits-all approach. Start by knowing your costs, what resources you have available, the needs of your cows and your goals. From there, don’t be afraid to ask around and try new methods to determine which feeding strategies best fit your operation. And of course, TEST YOUR HAY!

Listen: Casual Cattle Conversations Episode 35

Read more on hay and forage:
Understanding Forage Quality Analysis
Options for Producers When Facing Short Hay Supplies

Adapting to Virtual Fencing

Thu, 12 Sep 2024 15:42:18 GMT

As summer sets in, so does the routine of checking pasture fencing. Driving through cattle turned out on pasture usually entails some combination of looking at the water, counting cattle, watching for watery eyes, and checking fences. If the headcount is right, some will bypass the perimeter check assuming the weather hasn’t caused a rogue tree limb to raise concern. For those dependent on electric fences, a quick confirmation the energizer is maintaining the expected “charge” may also save running the whole fence.

There are several factors influencing the need to check fences regardless of type. The first is pasture availability, and the second is likely the cattle’s familiarity with the perimeter. This month, we look at cattle’s ability to adapt to virtual fencing as an alternative to permanent or electric fence perimeters.

Virtual fencing occurs in several ways and will vary by manufacturer. The systems use a GPS derived perimeter and cattle are fitted with battery or solar powered devices that communicate with the perimeter and provide audible warnings and electrical stimulation in the event audible warnings are not sufficient. Three Journal of Animal Science articles highlighted cattle’s ability to learn and adapt to the system while evaluating any related welfare issues.

The first time cattle are turned out in any new pasture they explore the perimeter and test the fences regardless of type—this is true of virtual fences as well. During the virtual fence training period, cattle required 7.9 paired (audible and electrical) stimulations to identify the perimeter boundary. As one might expect during the training period, the number of electrical cues cattle receive is higher than later in the grazing period. For cattle new to virtual fencing systems two principles are being learned: Audible signals indicate the perimeter is near and failure to respond to those audible signals results in an electrical correction.

This is not unlike a traditional electric fence training. Cattle unfamiliar with electric fences commonly test the boundaries and learn the consequences of “trying” the fencing. Once cattle learn the visual cue associated with a hot wire, most producers can get by for a few days even if the energizer fails due to the visual cue of the hot wire.

As the grazing period progressed, the ratio of audible to electrical signals increased, suggesting the cattle were learning to use the sounds to define the grazing boundaries. In these experiments not only was the perimeter effective at containing the cattle but the distribution of grazing was not different for electrical compared to virtual fencing. This suggests that regardless of visual or audible cues cattle stay about the same distance away from the fence on average.

Another hypothesis tested in these experiments was that cow age would influence the rate of adaptation to virtual fencing. I will let you decide whether young or old cows were expected to learn faster. Results suggest that while there was individual cow variation in adaptation rate to virtual fencing systems, age was not a significant factor in these individual animal differences. Young and older cows learned at comparable rates. In both age groups as the grazing period increased the number of electrical cues also declined. The authors indicated a cow’s ability to adapt to alternative fencing systems should not be influenced by age.

In addition to virtual fencing adaptation, cows were monitored for productivity and stress. Activity, lying behavior, milk production, body weight, and milk cortisol levels (stress measure) did not differ due to fencing method. The cow’s ability to learn cues and identify virtual boundaries suggest the stress of virtual fencing is not different from traditional fencing models. Uniform grazing distribution relative to the boundaries is key to ensuring ability to graze forage, gain weight and produce milk similar to cows in traditional fencing systems.

Virtual fencing is not likely to replace permanent perimeter fencing due to a host of risks related to cattle not responding to cues or respecting boundaries. However, the ability to use virtual fencing within an operations permanent boundary to expand grazing areas or implement managed grazing systems with reduced labor and less permanent or temporary infrastructure continues to show promise. As you find yourself repairing fence this summer, consider the possibility of checking and moving cattle using a virtual option.

For additional reading on virtual fencing:
Colorado Rancher Uses Grant Money for Virtual Fencing
Unleashing the Benefits of Virtual Fencing for Beef Producers

Research Shows Benefits of Grazing Livestock in Sagebrush Environments

Wed, 07 Aug 2024 12:59:31 GMT

While a cow grazing in a field isn’t typically remarkable, United States Department of Agriculture scientists have identified potential ecological benefits of strategically applied livestock grazing in sagebrush communities across U.S. western rangelands.

As recently published in the scientific journal Ecosphere , the collaborative research effort among Agricultural Research Service (ARS) rangeland scientists at Burns, Ore., and Fort Collins, Colo., challenged the outdated dogma that livestock grazing in the sagebrush steppe always negatively impacts these ecosystems and, in fact, can convey desirable outcomes, particularly in regard to limiting both wildfire risk and invasive annual grasses.

In addressing these ecological challenges, ARS scientists discovered that strategically applying livestock grazing prior to the occurrence of climate-induced wildfires can modify sagebrush steppe characteristics in ways that decrease fire probability and severity in the communities, promote biodiversity while reducing postfire annual grass invasion, fire-induced loss of native bunchgrasses, and fire damage to soil biocrusts, the collection of bacteria, fungi and mosses on the soil surface.

The ARS team compared moderately grazed and ungrazed sagebrush steppe and observed the grazing induced shorter flame lengths, slower rates of fire spread, and smaller burning fronts.

Similarly, strategic grazing in annual grass-dominated rangelands reduced flame length and rate of spread — modifications that resulted in safer and more effective fire suppression. Still another benefit of modified fire characteristics, the scientists reported, is a decrease in the area burned and overall mosaic of burned and unburned patches.

Grazing by non-native livestock such as sheep, cattle and horses dates back to the mid-to-late 1800s by Europeans, these early practices were not ecologically sustainable and led to widespread overuse and degradation to include loss of perennial grasses and forbs, reduced biodiversity, erosion, overabundant unpalatable species, and non-native plant invasions.

“There were concerns about the negative consequences of non-native livestock grazing in sagebrush communities, especially since these communities are experiencing unpreceded threats from invasive annual grasses, altered fire regimes, and climate change,” said Kirk Davies, ARS rangeland scientist. “But strategically applied grazing can spur desirable social-ecological outcomes such as reduced non-native annual grass invasion, decreased wildfire probability and spread, reduced fire suppression cost, and prevent undesirable ecological transformation post-fire.”

Davies’ findings also indicated that grazing can modify competitive relationships in introduced bunchgrass seeding to favor native species recruitment. This can be particularly valuable for reestablishing sagebrush, a critical shrub for many native wildlife species.

With careful attention to the timing, duration, frequency, and intensity of use needed to meet vegetation objectives, strategic grazing has the potential to reduce the detrimental impacts of invasive annual grasses, promote native species in introduced grasslands, and encourage native shrub recovery.

“Recognizing livestock grazing as a tool that can achieve desired outcomes could improve our ability to achieve meaningful rangeland management outcomes in sagebrush and likely other rangeland communities,” Davies said.

New Study Addresses Fescue Toxicosis Through Theraputic 5-HTP

Fri, 19 Jul 2024 10:38:00 GMT

Fescue toxicosis costs the cattle industry more than a billion dollars each year. Cattle producers will be interested in a new study beginning at the University of Kentucky aimed at the potential of hydroxytryptophan (5-HTP) in mitigating fescue toxicosis in beef cattle.

UK Martin-Gatton College of Agriculture, Food and Environment received a $300,000 grant for the research project aimed at the issue affecting beef production, especially in regions dominated by endophyte-infected tall fescue, according to a news release.

Department of Animal and Food Sciences assistant professor Ronald Trotta says fescue toxicosis reduces the weaning weight of nine million U.S. beef calves per year by an average of 50 pounds each.

Fescue toxicosis can cause reduced feed intake, increased vasoconstriction and susceptibility to heat stress, along with compromised gut integrity. This research is especially relevant to Kentucky, where 14 million hectares are covered with this type of fescue affected by ergot alkaloids.

“We will be focusing on the three primary fescue toxicosis symptoms,” Trotta explains. “The ergot alkaloids in fescue bind to specific receptors in blood vessels, causing vasoconstriction. This reduces blood flow to critical areas like the gut, decreasing nutrient absorption and activating the immune system.”

According to the release, the two-year study will evaluate the effectiveness of 5-HTP, a precursor to serotonin, in alleviating these symptoms. Increased serotonin bioavailability is expected to relax blood vessels, improve dry matter intake and reduce immune system activation, thereby counteracting the adverse effects of ergot alkaloids.

Using a multi-faceted approach, integrating nutritional, hormonal and transcriptomic analyses, researchers will examine gene expression in various body parts to understand how 5-HTP influences feed intake, vasoconstriction and gut health.

“We are conducting this study under very controlled conditions, using six animals per treatment group,” Trotta says. “This smaller scale allows for precise monitoring and comprehensive data collection.”

Trotta recently joined Martin-Gatton CAFÉ and shared his enthusiasm about this research’s potential impact.

“This project could offer a novel and effective strategy to mitigate the clinical symptoms of fescue toxicosis, significantly benefiting beef producers in Kentucky and beyond,” he says.

The research outcomes are expected to provide new insights into the molecular mechanisms of fescue toxicosis and the therapeutic potential of 5-HTP, contributing to improved animal health and agricultural productivity, according to the release.

Filling the Summer Forage Gap

Mon, 10 Jun 2024 14:33:44 GMT

Gaps in summer forages for livestock producers can be challenging. University of Missouri Extension agronomy field specialist Valerie Tate in Linn County shares management solutions, including planting warm-season annual forages such as pearl millet and sorghum-sudangrass to fill a void in summer forage production or when renovating forage stands.

“When moisture and soil nutrients are readily available, sorghum-sudangrass and pearl millet can produce up to 6 tons of forage per acre during the growing season,” Tate said.

Crops such as foxtail millet, Japanese millet or improved crabgrass can also be used but are not as productive, she said.

When to plant

Plant sorghum-sudangrass in mid-May to late June when soil temperatures reach 60 degrees. Drill sorghum-sudangrass at a rate of 20-25 pounds per acre, or broadcast it at a rate of 30-35 pounds per acre. For successful establishment, plant at a depth of ½ to 1 inch into a firm tilled seedbed, or control weeds with a burndown herbicide when using no-till. Drill pearl millet at a depth of ¾ to 1 inch deep at a rate of 15 pounds per acre or broadcast at a rate of 20-30 pounds per acre in mid-May through mid-June. Sorghum-sudangrass prefers a soil pH above 5.5. Pearl millet is more tolerant of acidic soils than sorghum-sudangrass.

How to maintain

The key to maintaining high-quality summer annual forage throughout the growing season is to keep the plants from becoming too mature. The first harvest can occur 45 to 60 days after planting. Harvest or graze sorghum-sudangrass and pearl millet when the plants reach 24 to 36 inches in height, leaving a 10-inch stubble to promote regrowth. If the plants are allowed to grow beyond 36 inches in height, forage quality drops dramatically. To maximize production, apply 60 pounds of nitrogen fertilizer at establishment and 40 to 60 pounds after each harvest.

Careful with grazing

Use caution when harvesting or grazing summer annual forages during periods of prolonged drought since nitrates can accumulate in the lower stems, resulting in nitrate poisoning. To minimize the risk of nitrate poisoning when conditions are dry and forage growth is slow, delay additional applications of nitrogen fertilizer until adequate moisture is available for rapid plant growth.

Prussic acid poisoning is also a concern with sorghum-sudangrass following frost injury or drought stress. Do not graze sorghum species before they reach 24 inches in height, and do not graze plants for 14 days after they have been stressed or damaged by drought, frost or hail.

Making bales

It can be difficult to get the coarse stems of sorghums and millets to the 18% dry matter necessary to prevent spoilage of dry hay. Making baleage by wrapping bales with plastic at a high moisture content is an alternative. Forage is mowed and allowed to wilt to 45% to 60% moisture. This may take 6-24 hours, depending upon the crop, yield, swath density and weather. After it is baled, it should be wrapped in plastic within four hours, if possible. The bales will undergo the ensiling process, which might take up to six weeks.

The keys to making high-quality baleage are:

Make tight, dense bales to eliminate as much oxygen as possible.
Make wet bales smaller than dry hay bales for ease of handling.
Use plastic twine or net wrap rather than treated sisal twine, which can break down the plastic.
Wrap with six layers of 1-mil white plastic.
Store bales in a well-drained area near where they will be fed.
Repair tears in the plastic with silage tape to avoid spoilage.

Related MU Extension guides

“Warm-Season Annual Forage Crops,” https://extension.missouri.edu/publications/g4661

“Growing Millets for Grain, Forage and Cover Crop Use,” https://extension.missouri.edu/publications/g4164

Cattle Chat: Summer Grazing

Wed, 29 May 2024 12:52:43 GMT

Pastures can be thought of in the same light as bank accounts. If an account holder withdraws a lot of money early in the year, then they’re left with nothing to spend on essential things down the line.

Beef producers who manage their pastureland in the same way can face similar repercussions.

Kansas State University veterinarians spoke about summer grazing management techniques that can keep pastures “in the black” on a recent episode of Cattle Chat .

“When we have cool-season grasses right now, they should be doing pretty well in most parts of the country and are very productive. Our warm-season grasses, depending on where you are, maybe haven’t quite come on yet,” K-State veterinarian Brad White said. “We need to think about our plan because both of those types of grasses have what are called dry spells where they’re less productive.”

K-State nutritionist Phillip Lancaster suggests introducing annual warm-season grasses to help balance out a pasture’s nutritional value when cool-season plants start to decline.

“Adding some annual warm-season forages to your grazing land rotation can be very beneficial so that you get something that is peaking in production when cool-season grasses are slowing down because of the heat,” he said.

Lancaster added: “When we get into the July and August timeframe, the cool-season grasses are not able to tolerate the heat, so their productivity slows way down.”

After cattle have grazed down cool-season plants, planting warm-season grasses like sorghum-sudangrass, pearl millet or crabgrass straight into those pastures, or overseeding, serves as a great option for grazing cattle, according to Lancaster.

“Crabgrass is actually a very good (plant) that doesn’t have the potential to introduce some of the animal health problems that sorghum-sudangrass can with nitrate toxicity, but those are still some good options as we’re thinking about planting.”

For producers who employ a rotational grazing plan, frequently monitoring the growth of the plants within a pasture plays a key part in keeping grass in good condition.

“As you’re rotating to new pastures, paying attention to previously grazed pastures and how they are recovering and regrowing can kind of tell you how fast you need to rotate animals to maintain that plant in kind of a vegetative state,” Lancaster said.

White agreed and added: “In terms of your pasture movement, some of those things need to be sped up or slowed down based on conditions. There’s no static.”

To capture the full benefits of grazing the cool-season plants within a pasture, it’s important they stay immature for as long as possible.

“One of our goals in some of these cool-season forage systems is to try to minimize that plant going into a reproductive stage,” Lancaster said.

White added: “So, keep it from going to seed and getting ‘stemmy.’”

To learn more about summer grazing, listen to Cattle Chat on your preferred streaming platform.

Better Pasture and Hay Conditions in 2024

Mon, 20 May 2024 15:44:48 GMT

As forage production moves into full swing, conditions for pasture and beginning hay stocks are in significantly better shape compared to last year. Released in the May Crop Production report from USDA-NASS, total U.S. hay stocks on May 1 were 21.0 million tons, up 46.6 percent year over year. That percentage speaks not only to improvement this year but just how bad last year was. The current May 1 total stocks are 8.9 percent higher than the 10-year average from 2013-2022. One year ago, the May 1 stocks were 25.7 percent below the ten-year average. The improvement in hay stocks indicates that producers generally got through the winter in better shape and still have some forage reserves going forward.

Figure 1 shows the May 1 hay stocks for the eight largest beef cow states. These states represent just over 51 percent of the total beef cow inventory of the country. May 1 hay stocks in the states in Figure 1 were mostly higher year over year, some significantly higher. Only Missouri and Kentucky had fractionally lower hays stocks this year. Hay stocks in these eight states are collectively up 81.4 percent year over year and are 9.4 percent above the ten-year average. These major beef cow states accounted for 54.0 percent of the total U.S. May1 hay stocks.

(Farm Journal)

May 1 is also when USDA-NASS begins the seasonal reports on pasture and range conditions. The second report of the year for May 13 shows that the percent of U.S. pastures and ranges in poor to very poor condition was 24 percent, compared to 33 percent at the same time one year ago. At the other end of the scale, 47 percent of pastures and ranges are currently rated in good to excellent condition, compared to 34 percent last year. Regional pasture and range conditions show significant improvement year over year. The Great Plains, including Kansas, Colorado, Nebraska, Wyoming, Montana, and North and South Dakota, have 12.29 percent of pastures and ranges in poor to very poor condition, compared to 31.29 percent one year ago. The Southern Plains, consisting of Oklahoma and Texas, have 26.5 percent of pastures in poor to very poor condition this year, compared to 47.5 percent last year. The eight states west of the Great Plains region have 14.63 percent of pastures and ranges in poor to very poor condition, compared to 20.5 percent one year ago.

The U.S. currently has less drought than anytime in the last four years. The Drought Monitor includes the Drought Severity and Coverage Index (DSCI), which combines the drought categories in the Drought Monitor into a single drought measure. The DSCI can take on values from zero to 500 and the current value of 51 is the lowest DSCI since April 2020. The DSCI reached a recent peak of 202 in late 2022.

Conditions at the beginning of the 2024 forage growing season suggest that producers may be able to plan grazing and hay production with less restriction compared to recent years. However, in many cases, pastures and ranges still need time to recover from extended drought conditions. There is reason to be cautiously optimistic for better cattle production conditions in 2024. However, the forecasted redevelopment of La Niña conditions this summer is worrisome. The seasonal forecast from the Climate Prediction Center is for above average temperatures and below average precipitation for the next three months in much of major beef cattle country. Proceed with caution.

Derrell Peel, OSU Extension livestock marketing specialist, talks about volatility in the cattle markets on SunUpTV from March 11, 2024 at https://www.youtube.com/watch?v=F8ija4US8W8

Swath Grazing

Mon, 20 Nov 2023 19:02:35 GMT

By Adele Harty and Olivia Amundson

Feed makes up the largest expense on a cow/calf operation. In addition to the initial expense, producers need to consider the storage and waste associated with winter feeding in the northern United States. As expenses increase, and producers evaluate more-efficient management techniques to lower production costs, one alternative may be to incorporate swath, or windrow grazing. Swath grazing can be utilized with various crops and can improve utilization of the crops for feed, while decreasing fuel, harvest and feeding costs and also improving soil health.

Swath grazing is the practice of cutting hay, small grains or forage crops and leaving them in windrows for livestock to graze during the winter months. Rather than having the expense of baling the hay, moving it off the field and feeding it in the winter, the feed is left in windrows, and cattle are allowed access to a limited number of windrows at a time as a means to reduce winter feed costs and increase soil fertility.

Benefits of Swath Grazing

Swath grazing has its benefits in the Midwest, where colder temperatures and snow accumulation regularly occur. If utilizing a small grain crop, such as, but not limited to, millet, sudan or sorghum, swath grazing may provide an additional opportunity to utilize the forage.

A study conducted at Iowa State University evaluated forage quality and utilization of swath grazing on the cow herd. Millet and sorghum were harvested in late July as a hay crop, allowed to regrow, and the regrowth was cut and raked in late December for a swath grazing trial. Cows in their third trimester of gestation were moved from corn stalk residue to the swaths, where they grazed in a similar method to intensive grazing. Cows were given enough swaths to graze for three days at a time, and then fencing was moved and cows were given access to the next section. Cow behavior became similar to that of an intensive grazing system, as cows became trained and knew what to do when they were supposed to move. The logistics of moving fencing during the winter can be a challenge, depending on temperatures and the situation, so take that into consideration, as ground temperature will affect fencing being moved during the rotation.

The nutrient value of the feed did decline toward the end of February when cows were switched over to a TMR; however, they saw no detrimental effects to the calves as a result. Cows were able to utilize the feed with up to 12 inches of snow accumulation and temperatures of -20 degrees Fahrenheit. Forage utilization was up to 70%, which makes swath grazing a cost-effective option in comparison to putting the forage in bales. With swath grazing, operating equipment and labor decrease, as harvesting and moving bales or manure hauling are minimal. The study also found that grazing crop residue was minimal and did not affect regrowth of a perennial forage crop, thus allowing grazing to occur on a hay field or permanent pasture.

From a soil health perspective, swath grazing increases soil health through manure and urine distribution. In a dry year, it helps create a potential seedbed and improved filtration by breaking soil crust, fully trampling all the non-eaten materials, and spreading out dung piles, making them less fly friendly. This also provides a food source for soil microbes, thus increasing fertility of fields in the long-term.

Considerations of Swath Grazing

This can be a more labor-intensive method of grazing and mimics a management-intensive grazing system. The labor required is to move the cattle and fencing in relation to appropriate stocking density, but it is important to compare daily feeding of harvested forages to determine if there truly are labor differences. A reliable winter water source will be vital to the success of this system and could increase labor and time requirements.

It’s also important to consider animal performance for those animals that are utilizing the swaths. As the forage quality declines, this system may not be suitable for lactating cows, as their nutrient requirements are the highest. However, applying this method to cows in mid-to-late gestation, stocker calves or replacement females, could be a cost-effective and efficient alternative.

Windrow Grazing Annual Forages to Extend the Grazing Season

Wed, 20 Sep 2023 19:12:13 GMT

In many areas of central and eastern Nebraska, drought conditions have resulted in reduced forage production on rangeland and pasture. This is resulting in a shortage of feed for many producers and a need for forage between now and when cornstalks are available for grazing. Windrow grazing annual forages allows producers to cut the crop at an optimum time for quality and increase harvest efficiency through strip grazing the windrows.

Advantages to Windrow Grazing

Harvested feed costs can be one of the largest expenses to cattle producers. Windrow grazing, sometimes called swath grazing, is a management practice that can significantly reduce harvesting and feeding costs. Swathing the crop and leaving the windrows in the field provides several advantages.

• Eliminates the costs of baling and hauling bales off the field.
• Reduces labor and equipment costs associated with feeding.
• Returns some nutrients and organic matter from consumed forage back to the soil where the crop was grown.

Precipitation Patterns Support Windrow Grazing in Central and Western Nebraska

In Nebraska, 75-80 percent of seasonal precipitation falls in the six-month period from April through September. Only 20-25 percent of precipitation falls from October through March. This seasonality of precipitation allows for swathing forage crops in early fall and preserving them through the fall and winter with minimal deterioration in quality due to weathering. Cool, dry conditions frequently associated with late fall and winter in Nebraska are favorable for preserving forage in a windrow.

Across Nebraska, the average amount of precipitation increases from west to east. Greater average precipitation in eastern Nebraska does increase the risk of windrow deterioration compared to drier conditions in central and western Nebraska.

Windrow grazing of warm season annual forages such as foxtail millet, sudan grass and sorghum x sudan grass hybrids can provide an excellent way to harvest these forages when they are at an optimum for quality and efficiently utilize them with minimal waste. Windrow grazing of cool season annual forages such as spring triticale, oats and spring barley planted in late summer can provide high quality feed for late fall and winter grazing as well.

Snowfall from October through March can be quite variable; however, extended periods when snow cover would prevent windrow grazing are limited. If cattle know that the windrows are present, they will dig through the snow to get to the windrows.

Nitrate Risks with Windrow Grazing

When windrow grazing annual forages, nitrate poisoning is a potential risk. If possible, clip forages prior to swathing and have a nitrate test conducted to see what level of nitrates are present. If nitrates are high, raising the cutter bar higher can help to reduce the nitrate levels in forage placed in the windrow, as nitrates tend to be concentrated in the bottom third of the stem. Annual forages placed in the windrow should also be tested for nitrates prior to grazing. If nitrate levels are too high for grazing safely, the crop can be baled and then ground and mixed with other feeds to dilute the nitrates to a level that is safe for feeding.

A webinar titled Windrow Grazing in Nebraska is available that highlights more of the details of using this management practice at http://beef.unl.edu .

A UNL NebGuide Windrow Grazing (PDF version, 623KB) is available as a resource as well.

No Bumper Hay Crop, 44% of the Cattle Inventory In Drought

Tue, 12 Sep 2023 19:53:14 GMT

Dry conditions persist across parts of the U.S., with nearly half of the nation’s corn crop and 37% of the nation’s hay crop areas experiencing drought, reports Clinton Griffiths on AgDay.

Specifically, several major growing areas and livestock production states, including Nebraska, Kansas and Missouri, are feeling drought pressure.

“Certainly, when you look at Missouri in particular, we’re down in hay production in 2023,” says Scott Brown, markets and policy professor and interim director of the Rural and Farm Finance Policy Analysis Center at the University of Missouri. “Other states have recovered—some of the states that had more of a drought issue in 2022 than this year—but we’ve kind of been front and center of the dry weather that’s hurt pastures and hay and ponds.”

According to the USDA’s National Agricultural Statistics Service (NASS), released on S ept. 12 , overall yield per acre in all hay harvested is forecast to be slightly higher from 2022 (2.28 tons per acre) to 2023 (2.29 tons per acre). Production across the U.S. iss also forecast to increase in 2023 by nearly four million ton.

However, as Brown notes, total hay production was expected to fall significantly short across some states compared to last year, including Iowa, Minnesota and Missouri.

Heading into the winter feeding months, tight hay supplies leading to further liquidation of cattle in these areas is cause for concern.

“It sure seems like, to me, that’s where we’re headed,” Brown adds. “It’s almost every segment of the industry that we can see that consolidation—all the way from the cow-calf level to the processing and retailers.”

Brown explains that the cattle industry’s large number of participants throughout the supply chain may need to coordinate—leading to concentration or consolidation of the industry.

Meanwhile, overall pasture and range conditions in the U.S. seem to be holding on to improving slightly over the 2023 growing season.

(Farm Journal)

The next few months could be pivotal for the cattle industry if drought persists, encouraging producers to further liquidate the cattle herd. As of now, 44% of the cattle inventory is in an area of drought—the highest percentage since the start of the season in late April, Griffiths reports.

Late Season Pasture Fly Control: What You Need to Know

Mon, 28 Aug 2023 14:55:59 GMT

Late August and September usually signal pasture fly season should be ending. However, over the last few years our fall seasons have remained warm, sometimes well into early November and flies persist at problematic levels longer than typical.

This upcoming fall season may be no different based on several meteorology forecasts. If these predictions hold true, pasture fly control efforts may be required through late fall.

To reduce late season, fly stress on pastured cattle, a review of the common fly pests of pastured cattle, control methods and available products can be helpful.

Horn Fly

[Nebraska] livestock producers normally see two horn fly population spikes, one in early June and the second in late-August through mid-September. The second peak is due to the buildup of the continuous and overlapping fly generations that develop through the season. Depending upon weather patterns these fly populations may be reduced by a fall cold front that sometimes occurs in September. However, if temperatures remain warm horn fly numbers will remain high. Diapause, a biological event triggered by cool fall temperatures naturally lower horn fly numbers. Development from egg to adult is interrupted and instead development stops at the pupal stage that overwinter beneath manure pats. Diapause for horn flies in Nebraska begins when temperatures within the manure pat drop below 60º F. However, existing adult flies will persist through September and October or until a killing frost occurs (below 25º F).

However, if adult flies continue to emerge a rescue fly treatment may be necessary if numbers exceed the Economic Injury Level of 200 horn flies per animal. Insecticidal sprays, either using a low-pressure sprayer or a mist blower sprayer are an effective option. These applications should provide 7 – 10 days of control. A pour-on treatment is another option and provides control for 21 – 28 days. A list of recommended treatment methods and control products are in Table 1.

(Farm Journal)

Face Fly

Numbers have been high this season, especially in areas of the state where rainfall was abundant. Face flies experience a version of diapause, called reproductive diapause. Reproductive diapause occurs when daylength shortens to 12.5 hours or less, beginning in Nebraska around the middle of September. During this process both sexes seek protected places to spend the winter. A killing frost (25° F degrees or below) can impact face fly numbers. However, until diapause is completed, or a killing frost occurs, additional fly control measures may be required.

Face fly control is extremely difficult to accomplish due to the feeding habits of the female, which seek protein from the eyes, nasal area, and other orifices of livestock. Treatment products directed to the face or head area of animals will provide the best control. A list of pour-on and spray products available can be found in Table 2.

In Nebraska, face flies seeking shelter for overwintering often move to buildings and homes. They usually cluster in attics or wall cavities of structures located closest to pastures. The first step in keeping insects from entering structures is exclusion.

To prevent home and structure infestations inspect for points of entry such as around doors, windows, soffits, and vents and use caulk to seal up holes in those areas. Residual sprays containing bifenthrin, deltamethrin or permethrin can also be applied as perimeter barriers.

(Farm Journal)

Stable Fly

High numbers may still be present in areas of Nebraska after September, especially in areas of the state where rainfall was abundant. Stable flies will continue their feeding activity on livestock until we receive a hard freeze. Spray applications provide the best means of reducing their numbers and should be made every 10 days. The sides of buildings or tree windbreaks where large numbers of stable flies are observed resting can also be treated.

Applications to resting sites should be made on a warm sunny day usually near mid-afternoon. Applications to either animals or fly resting sites can be made with a low-pressure or a mist blower sprayer. A list of recommended control products is in Table 3.

(Farm Journal)

Peel: Oklahoma Forage Production Rebounds

Mon, 21 Aug 2023 21:30:26 GMT

Although drought persists north and south of Oklahoma, forage conditions have improved greatly in the state this summer. In late April, at the peak of drought this spring, over 64 percent of Oklahoma had some degree of dry or drought conditions with about 50 percent of the state in D2-D4 drought in the Drought Monitor. In mid-August, just 5.35 percent of the state had D2 or worse drought.

In May, the first seasonal NASS conditions report for 2023 showed that 54 percent of Oklahoma range and pastures were in poor or very poor condition. July was the seventh wettest July on record in Oklahoma. Most of the rain fell in the first half of July and by mid-July just eight percent of ranges and pastures were rated poor to very poor. By mid-August, hot, dry summer weather decreased range and pasture ratings in Oklahoma pastures to 20 percent poor to very poor.

In the August Crop Production report, USDA-NASS provided estimates of alfalfa and other hay production for major hay producing states. Oklahoma total hay production in 2023 is estimated to be up 58.2 percent year over year from the drought-reduced levels of 2022 and up 18.3 percent over the twenty-year average from 2002-2021. Total U.S. hay production is up 5.3 percent year over year.

Other hay production in Oklahoma is up 60.3 percent year over year and alfalfa hay production is up 41.8 percent over one year ago. Other hay typically makes up about 88 percent of total hay production in Oklahoma and 2023 production of other hay in Oklahoma is the highest on record in data back to 1974. Other hay production is up due to both a 17.9 percent increase in harvested other hay acreage over last year and a 36 percent year over year increase in other hay yield. In 2023, Oklahoma is the number two hay producing state following Texas and out-ranks several major hay producing states that typically produce more hay than Oklahoma, including Missouri, California, Nebraska, and South Dakota.

The sharp increase in hay production will restore the hay supply in Oklahoma to more typical levels after the drought-reduced level last year. This is despite the May 1 hay stocks level that was equal to the low level in 2007 and the lowest since 1979. The total hay supply for the coming year is the sum of May 1 hay stocks (beginning of hay crop year) plus current year hay production (Figure 1). Recover in forage conditions should allow cattle producers to stabilize herd inventories and likely begin some heifer retention.

(Farm Journal)