Grazing Management Plans

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.

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.

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

Oregon Ranchers Are Continuing to Battle Grueling Wildfires as Financial Losses Mount

Wed, 07 Aug 2024 18:10:08 GMT

As of Friday, more than 1.1 million acres has burned in Oregon. Lightning continues to spark new fires and with the flames still not under control, it will go down as one of the most devastating wildfire fires in the state’s history.

Clint Sexson ranches in eastern Oregon. He says between cattle lost and grazing areas burned, it’s been a grueling summer. The exact livestock losses are unknown at this time.

“I don’t even want to speculate,” Sexson says. “I mean, the one that’s pretty public is that the 300 head in the Durkee Fire that were lost,” Sexson says. “I know one producer who has lost probably hundreds.”

That particular fire, the Durkee Fire, has been a monster. At 86% contained, it’s already scorched 295,000 acres.

Plenty of Fuel for Fires

Just this week, lightning sparked more fires. Sexson says the reason the fires have been so bad is the amount of grass available to fuel the fires.

“There’s more fuel on the ground,” Sexson says. “Some of these areas have burned before. There hasn’t necessarily been a clean up after a burn, so there’s just a lot of fuel.”

A Devastating Loss of Grass to Graze

The livestock losses are heartbreaking and severe, but the amount of grass burned is causing concern in the state. As the fires rage, the losses of valuable grazing ground are mounting, which impacts livestock producers across the state.

“This part of the world is different,” Sexson says. “A lot of people don’t feed cows, but maybe 30, 60 days a year. The rest of the year, we are grazing cattle. It’s a budgetary thing and a management thing that they will have to work through. Emotionally, it’s tough on those people, especially those generational ranches.”

Sexson was fortunate. On July 20, as the fires raged and closed in on his land, he was able to get cattle out thanks to fellow ranchers who showed up with trucks and trailers.

“I work for Select Sires and every one of those trucks that showed up, they were all customers,” he says, as his voice cracks and tears fill his eyes. “We got the cattle out and right back to a customer’s feedlot. They were ready for them, and we were pretty fortunate.”

An Emotional Sale of Support

That emotion was felt late last week as Superior Livestock Auction sold special benefit lots as part of their video sale in Winnemucca, Nev. This was an example of ranchers helping ranchers. That money went to the Oregon Fire Relief Fund, which will help those producers in need.

“These are primarily purebred breeders who have made donations in sale credit or semen credit,” Sexson says. “They’re not directly focused on their customers alone. They’re just focused on the general beef industry in Oregon and the devastation some of these people are dealing with. I know two or three people who had their entire ranches burned by the fires. They may not have lost a cow, but it burnt all their private grazing ground.”

The special sale was a touching gesture, as the ranching community comes together at a time of need and the fires continue to burn. Emotions are high, losses are mounting and cattle producers impacted are feeling the financial pain.

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.