Bulls

Stopping Flies in 2026: 4 Steps to Battling These Economic Pests

Wed, 06 May 2026 14:27:47 GMT

With fly season approaching, now is the time to evaluate and refine your fly management plan for 2026.

“Every year, stable and horn flies cause significant economic losses, but a good fly control program can minimize this impact,” says Cassandra Olds, Kansas State University Extension entomologist. “Although often grouped together, these are very different flies that need different control approaches.”

Dr. Ashby Green, Neogen senior technical services veterinarian, says, “If you are seeing flies, ticks, lice or insect damage to your cattle herd, we know there is an economic impact; however, that impact can become far greater than production or weight gain loss alone. Insect pressure affects grazing patterns of cattle; it affects their comfort and it can lead to health issues. Some of those health issues can be definite, such as anaplasmosis.”

The vectors responsible for spreading anaplasmosis include horse flies, stable flies and ticks. This condition has been reported in most states across the U.S., while the disease has been recognized as endemic throughout the South and several Midwestern and Western states.

Jonathan Cammack, Oklahoma State University assistant professor and state extension specialist, says, “With horn flies, we’re looking at mastitis risk, so that’s going to impact both dairy cattle and also our cow-calf operations. A lot of times, horn flies will feed on the udders of the animals, and they transfer the Staphylococcus aureus bacteria because they land on the manure, then they go back to the animal to feed and bring those bacteria with them.”

Several other conditions are propagated by flies, including pinkeye, which can be spread by face flies and causes inflammation and ulceration of the eyes. Pinkeye-affected calves are, on average, 35 lb. to 40 lb. lighter at weaning compared to healthy calves, according to a University of Kentucky report.

Cammack predicts flies are costing the U.S. cattle industry $6 billion annually in losses.

“That encompasses everything from actual loss in production due to decreased weight gain or decreased milk production, veterinary needs associated with treatment of cattle with exposure to pathogens from some of these insects, and then also the control measures associated with managing those individual fly species,” he explains.

David Boxler, Nebraska Extension livestock entomologist, says if previous control efforts underperformed, consider adjusting your approach.
“The best control method will depend on several factors including efficacy, cost, convenience and your current herd management practices,” he summarizes.

He also reminds producers that horn flies can migrate from neighboring untreated herds, masking the effectiveness of your efforts and increasing fly pressure. For this reason, Boxler recommends a comprehensive, integrated fly control.

Olds shares these tips for stopping flies, or at least reducing their impact:

Step 1: Know What You Have

“The first step in developing a good fly control program is knowing who you have,” Olds explains.

(Kansas State University)

Horn flies feed 20 to 30 times a day and stay associated with their chosen animal 24/7, with females only leaving briefly to lay eggs. Stable flies in contrast only feed once or twice a day, remaining on the host for a short period of time (3 to 5 minutes).

When not feeding, flies are resting in shaded areas such as building sides and vegetation. This short feeding time means producers often underestimate their stable fly burdens. While both flies affect pastured cattle, horn flies are not a problem in confined settings such as dairies and feedlots. This is because horn flies need fresh, undisturbed manure as a breeding site while stable flies can develop in any decaying plant matter such as hay bales, feed bunk spill over and decaying grass.

“Their populations can build rapidly and often exceed the economic injury level defined as 200 flies per animal,” Boxler adds about horn flies. “Once fly numbers surpass this threshold, cattle experience reduced weight gain and milk production due to fly-induced stress and altered grazing behavior.”

Step 2: Reduce Populations

Olds explains with either fly species, using non-insecticidal control methods is essential for slowing insecticide resistance. For horn flies, pasture burning in spring kills any flies overwintering, which can significantly reduce fly populations emerging as weather warms. A healthy dung beetle population will also significantly reduce your fly numbers for free.

“Dung beetles are very susceptible to macrocyclic lactones so avoid using injectable and pour-on avermectins (abamectin, eprinomectin, ivermectin etc.),” Olds says.
Because horn flies die within hours of being removed from cattle, non-chemical walk-through traps can be effective if animals pass through it regularly.

Step 3: Eliminate Breeding Grounds

Round hay bales result in significant wastage, which when mixed into the manure-contaminated mud around bales provides a prime breeding site for stable flies.
Olds explains each round bale can produce 200,000 stable flies.

“Reducing hay waste and spreading/drying areas around finished bales is key to reducing stable fly numbers,” she says. “In feedlots, minimizing feed spillage and waste is critical to remove breeding sites for stable and house flies.”

Parasitoid wasps are available from multiple sellers and should be released around fly breeding sites. These are very effective if released before fly populations emerge and released repeatedly through the fly season.

Be careful using insecticides if using parasitoid wasps as they are very small and sensitive to these chemicals. Keeping vegetation surrounding pen areas short and exposed will remove sheltered resting areas, making life more difficult for the flies.

Step 4: Consider Chemical Control Options

Olds stresses chemical control options should be used as a supplement not the basis of a fly control program.

(Kansas State University)

“For horn flies, insecticidal ear tags are an effective method of control if correct rotation is used,” she adds. “Rotate the chemical class of your tag annually, in year one using pyrethroid-based products, year two use organophosphate-based products and year three use macrocyclic lactone tags. Repeating this three-year cycle will reduce the selection pressure on the fly populations, slowing down the spread of resistance.”

Olds also shares these tips for effective tagging: “Tag both ears and place the tag directly into the ear. For the tag to be effective, it must come into direct contact with the animal’s skin, which is greatly reduced when daisy chained.”

Little of the tag touches the body when attached to another tag.

(Cassandra Olds, Kansas State University)

She also instructs producers not to tag young calves and adds mature bulls with thick necks might not benefit from tagging unless the tag can touch the skin.

“Although the box may label products as effective for four to five months, field trials have shown that tags only remain effective for 90 to 100 days,” Olds says. “If possible, wait until fly populations are noticeable before tagging animals to get control over peak fly activity period. After 90 days, remove the tag to reduce the risk of insecticide resistance developing.”

(Neogen)

To increase coverage, pour-ons of the same chemical class as the ear tag can be used to increase coverage.

“Be aware that a macrocyclic lactone pour-on will impact dung beetle populations,” Olds says. “Make sure animals are dosed accurately according to weight and ensure head to tail coverage. Due to their low contact time with the host and preference for the legs, topical insecticidal treatments are generally not useful against stable flies.”

Spraying the legs can provide some relief, although it should be used sparingly as most sprays are pyrethroid-based, not allowing for effective annual rotation. Baits and premise sprays can be useful in controlling both house and stable flies, look for areas where flies are found resting such as building walls, fence posts and inside sheds and shelters.

Another option is feed through insect growth regulators (IGRs) to control horn fly. Olds says it is important cattle consume the correct amount, which can be difficult under free-choice conditions.

“Under-dosing will result in resistance developing over time, reducing product efficacy,” she says. “Although labeled for stable fly control also, when manure containing the IGR is diluted in the mud and hay, it is no longer effective.”

Often marketed as dung beetle safe, Olds says evaluations of these claims in most species have not been carried out, and their true impact remains unknown.

“Insecticide resistance to IGRs can and does happen; to slow this, rotate annually between Methoprene-based (Group 7A) and diflubenzuron-based products (Group 15),” she adds.

The Veterinary Entomology website , veterinaryentomology.org/vetpestx, provides a searchable database that can help producers select the right products. Producers can select from type of animal, insect and application method.

“For on-animal use, select the best product to allow an annual rotation between pyrethroid (Group 3A), organophosphate (Group 1B) and macrocyclic lactone (Group 6) groups,” Olds says.

Green also recommends using a multi-pronged approach to insect control. He says fly tags, IGR products, pour-ons, back rubbers and dust bags can help diminish the population.

“Both back rubbers and dust bags can be highly effective if managed correctly,” Green advises. “Keep in mind, when these are put out to withstand the elements, including moisture and rain, it’s key to keep the dust fresh or the oil recharged in your back rubbers. Otherwise, they will diminish in their ability to control flies quickly.”

Cammack stresses the importance of accurate dosing by the individual animal’s weight and following label guidelines.

To best control flies and insects on cattle operations, “the easy and effective way is the best way,” Green summarizes. “It’s up to you and with the help of your veterinarian to help create that combination.”

Stop the Guesswork: Build a Targeted Parasite Plan

Mon, 04 May 2026 13:51:51 GMT

As grass greens up and cattle head back to pasture, many producers are “throwing darts in an open field” when it comes to parasite control, says Tennessee Hereford breeder Ryan Proffitt.

The real-world frustration of deworming programs is knowing if they are working, Proffitt says.

Norbrook Technical Services Veterinarian Megan Bollin explains fecal egg count testing, targeted treatment, concurrent deworming, maintaining refugia and smarter pasture management can turn parasite control guesswork into a targeted plan that protects herd health, preserves dewormer efficacy and ultimately adds pounds to the calf crop.

Both Bollin and Proffitt agree a pragmatic roadmap for modern parasite control is anchored in diagnostics, targeted treatment and strong relationships with veterinarians.

Bollin shares five practical strategies to get the most out of today’s dewormers and preserve them for tomorrow:

1. Sit Down with Your Vet.

She encourages producers to map out a herd‑specific internal and external parasite plan with diagnostics built in.

“Your local vet should be your key partner in designing a program that fits your parasites, climate and management style,” Bollin says.

2. Use the Right Product at the Right Time.

Use the correct class, correct dose and consider concurrent deworming when resistance is a known issue. Your local veterinarian can guide you on proper treatment timing to avoid wasting money.

3. Manage Pastures with Parasites in Mind.

Bollin says pasture management is as important as treatment. Pasture type, quality, topography and drainage should all be considered in your plan, knowing we can’t always do much to change them.

“Only about 10% of the parasite life cycle is in the animal; 90% is on pasture,” she says.

Larvae generally stay below 4” on the grass blade. She says it is important to avoid overgrazing pastures below this height and manage stocking density accordingly.

“When you get a big rain after a drought, the larvae that had been waiting in the manure pats can quickly become infective and significantly increase the risk of infection, especially in young calves,” she says.

4. Prioritize High-Risk Animals.

Calves, stockers, bulls and replacements should be prioritized with the strictest parasite control and monitoring programs.

“Calves, replacement heifers and bulls are typically heavier shedders and more susceptible to the effects of parasites than mature cows,” Bollin explains.

Proffitt notes that many producers historically concentrate on keeping mature cows dewormed while underestimating calves’ role as carriers.

“We don’t need to, and shouldn’t be, treating every animal like we always have,” Bollin adds. “That has gotten us in a pickle with resistance.”

5. Measure and Adjust Treatment.

Bollin says it is important to know where you started. Get a baseline fecal egg count, understand your resistance patterns and monitor the efficacy of your treatment program. So many variables change from year to year: climate, weather conditions, new animals and other stressors. It’s critical to routinely evaluate your deworming program and avoid blindly doing the same thing year after year.

(Proffitt Family)

Diagnostics Are Essential, Not Optional

Fecal egg count reduction tests (FECRTs) are the most practical method we have to determine if dewormers are still working and at what level.

Bollin explains the process includes:

Collecting rectal fecal samples and recording identification.
Treating animals with product or products of choice.
Resampling the same animals by taking rectal fecal samples, 10 to 17 days later, depending on the drug or drugs used.

The lab will count how many eggs per gram are in that fecal sample. There will be a pretreatment and a posttreatment sample. Bollin says the goal should be greater than 95% reduction.

Proffitt argues FECRTs are worth the hassle.

“If we don’t have a game plan on what we’re doing and we’re just rushing,” he says. “What did we win at the end of the day if we don’t know what we’re doing?”

Proffitt says testing tells him which cows he can skip treating, which saves him money.

Bollin explains in many cases mature cows 3 years and older, shedding low levels of eggs, on a good plane of nutrition, with no other stressors or health concerns (including liver flukes), should not need to be dewormed.

“This supports ‘refugia’ — intentionally leaving low-risk animals untreated to slow resistance,” she explains. “Because they’re mature, they’ve got a competent immune system that can actually fight off these parasites by themselves without a dewormer.”

To reduce costs further, Bollin says producers can pool fecal samples from multiple cows into a single submission.

(Deb Gustafson)

Beating Parasite Resistance Starts at the Chute

Bollin says dewormer resistance, long documented in sheep and goats, is being seen more frequently in U.S. cattle herds.

She says overuse, underdosing and treating every animal regardless of need are major drivers in resistance.

“All of these deworming products, when they were originally approved, had very high levels of efficacy. We’re talking 99% and above,” Bollin explains. “As we’ve continually used these products, efficacy has been challenged because resistance has increased.”

If you’re using products that are no longer effective in your herd, you’re spending money on drugs that don’t work, and you’re not getting the production benefits. One way to restore efficacy when resistance is present is to use concurrent deworming.

Why Concurrent Deworming Matters

Bollin says concurrent deworming is using two dewormers from different classes at the same time. She stresses producers need to work with a veterinarian to avoid unknowingly pairing two products from the same class, which doesn’t provide the intended benefit.

She explains the benefits of concurrent deworming are:

· Higher overall efficacy when two partially effective products are combined. “Say you’ve got two products, for example, each with 70% efficacy. By using them together, you can raise your overall efficacy to levels exceeding 90%,” she says.

· Broader spectrum of parasite coverage.

· Models would suggest a slowing of resistance.

· Only sustainable long-term when used in conjunction with a refugia program. This means we don’t treat every animal. We want to keep a few “good” worms around that are still susceptible to the drug.

Bollin gives the example of pairing a benzimidazole, or a “white dewormer,” such as fenbendazole, albendazole or oxfendazole, with a macrocyclic lactone such as ivermectin, moxidectin or eprinomectin.

She emphasizes the industry unfortunately doesn’t have a lot of studies looking at this, but a study published in 2025 highlighted the benefits of concurrent treatment with fenbendazole in situations where resistance to macrocyclic lactones is likely.

Dung Beetles Are Valuable Allies

Dung beetles break up manure pats, exposing eggs and larvae to sunshine and dry conditions. Some dewormers are more compatible with dung beetle health.

“Two of the dewormers that are not harmful are moxidectin and fenbendazole,” Bollin says. “Those are two molecules that are generally safe for dung beetles, and those could be a good option to pair together.”

Facility where researchers collect blood samples and weigh cattle before and after they are transported. Steers have painted numbers on their backs so their activity can be followed on camera.

(Stephanie Hansen)

Application Technique and Dosing Accuracy Matter

Bollin says accurate body weights, not visual estimates, are critical, explaining underdosing is a key driver of resistance.

“One of the biggest contributors to resistance is that we are just not giving them enough active ingredient,” she says. “If you don’t have scales, it is best to treat to the heaviest body weight in the group, so that you make sure that they’re all getting enough.”

She also stresses the importance of storing deworming products correctly.

“Leaving them by the chute in temperature swings can reduce efficacy,” she says.

Proffitt also reminds producers to read labels and understand rain windows with pour-ons and to avoid mud or manure on hides. Bollin notes that injectables can provide more certainty that the animal is getting the full dose, whereas oral drenches can be spit out and pour-ons can run off or be groomed off by penmates.

Both Bollin and Proffitt frame parasite control not as one more chore on an overloaded to-do list but rather as a strategic, data-driven opportunity to protect animal health, slow resistance and convert good management into pounds sold.

Your Next Read:

Determine Parasite Load and Follow With Treatment

What the Semen Microbiome Reveals About Bull Fertility

Fri, 24 Apr 2026 17:05:33 GMT

Bacteria in bull semen have long been viewed as a problem to manage. New research suggests they may also be a signal to interpret. A recent study published in Animals from the St. Petersburg State University of Veterinary Medicine links the semen microbiome to fertility outcomes, raising a different question: What does that microbial profile reveal about the bull itself?

How Bacteria in Bull Semen Have Traditionally Been Managed

For years, the focus has been on controlling bacterial populations in semen to protect sperm function and prevent disease transmission. Hygiene protocols, extender formulation and antibiotic inclusion all reflect that priority.

This approach has been effective for preserving semen quality and limiting biosecurity risks. It has also shaped how fertility is evaluated. Motility, morphology and concentration remain the primary metrics, each focused on the sperm cell itself.

What this framework largely excludes is the biological environment surrounding those cells.

What a New Study Shows About the Bull Semen Microbiome

The new work set out to characterize that missing layer. Using 16S rRNA sequencing, the authors profiled the semen microbiome across bulls, quantifying both microbial diversity and the relative abundance of bacterial taxa.

Rather than treating bacteria as background noise, the study evaluated microbial communities as a variable of interest. The analysis identified dominant phyla within bull ejaculates, including Proteobacteria, Firmicutes, and Actinobacteria, with measurable variation between individuals.

The study then examined how those microbial patterns aligned with fertility outcomes. The result was not a single causative organism, but a set of associations between microbial profiles and reproductive performance.

They found bulls with excellent quality semen had a higher abundance of Actinobateriota: from around 2% of the microbiota of low-quality sperm to around 14% in excellent-quality sperm. Further, Bacteriodes fagilis was detected in 75% of samples of low-quality sperm, while it was only in 20% of excellent-quality sperm samples.

It is important to note the study did not test whether bacteria influence fertilization directly, but whether the microbiome tracks with differences in sperm quality.

Is the Semen Microbiome Random or Structured?

One of the most consistent findings across studies is that the semen microbiome is not random.

The dominance of a small number of bacterial phyla observed in the Animals study aligns with earlier work. For example, Cojkic and colleagues reported bull semen microbiota are structured and repeatable, with Proteobacteria often comprising a large proportion of total abundance.

At the same time, variation between bulls appears to be meaningful. In the Animals study, microbial composition differed across individuals, and those differences aligned with fertility outcomes. Similar patterns have been reported by Koziol and colleagues who found significant differences in microbial communities between bulls with satisfactory versus unsatisfactory semen quality.

Taken together, these findings support a shift in interpretation. The semen microbiome behaves less like noise and more like a measurable, variable characteristic.

Does the Semen Microbiome Affect Fertility or Reflect It?

The central question is not whether the microbiome is associated with fertility. Multiple studies now support that conclusion. The question is what that association represents.

There is a plausible case for biological interaction. Work from the University of Georgia reported associations between microbial composition and sperm function, including motility and mitochondrial activity, with statistically significant differences observed between microbial profiles.

These findings suggest microbial communities could interact with sperm physiology under certain conditions.

However, the alternative explanation remains equally important.

Microbial composition has also been shown to shift with external and host-related factors. Studies from North Dakota State University and the Swedish University of Agricultural Sciences have documented changes in semen microbiota associated with age, environment and management conditions, with measurable variation in dominant taxa across groups.

These patterns indicate the microbiome may reflect the broader physiological and environmental context in which sperm are produced and handled.

Taken together, the available evidence supports a cautious interpretation: The microbiome may not be acting on fertility. It may be reporting on it.

A Missing Layer in Bull Evaluation

If that interpretation holds, the implications are practical.

Current fertility evaluation tools focus on the sperm cell. Motility, morphology and concentration provide valuable information, but they offer limited insight into the biological context surrounding those cells.

The semen microbiome introduces a potential additional layer. By capturing aspects of the reproductive tract environment and systemic conditions, microbial profiles may help explain variability that is not accounted for by conventional metrics.

Emerging work supports this direction. Integrative approaches combining microbiome, genomic and metabolic data have reported improved prediction of fertility-related outcomes compared to single-measure approaches.

At the same time, these approaches remain in early stages of development and are not yet part of routine evaluation.

Before the Semen Microbiome Can be Used in Practice

Translating microbiome data into practical tools will require further refinement. Across studies, reported microbial compositions vary depending on sampling technique, sequencing platform and analytical approach, making it difficult to define consistent reference ranges or thresholds for interpretation. It also remains unclear whether diversity metrics, specific taxa or broader community structure will prove most informative for evaluating fertility.

At the same time, none of this diminishes the importance of bacterial control in semen processing. Hygiene and antibiotic use remain essential for maintaining semen quality and preventing disease transmission. However, research indicates bacterial populations can persist despite these measures, with detectable microbial communities present even after standard processing and antibiotic inclusion.

Taken together, these findings point to a subtle shift in perspective. For years, the focus has been on controlling bacterial populations in semen. Emerging research suggests they may also be worth interpreting. The value of the semen microbiome may not lie in changing fertility outcomes, but in helping explain them.

Bulls Remain the Weak Link in Trichomoniasis Control

Thu, 02 Apr 2026 20:01:59 GMT

A breeding season can appear routine until the pregnancy check tells a different story. Conception rates fall short of expectations, cows return to heat off schedule and open females begin to stack up. What looks like a management issue is often something far more specific and far more costly.

Across the U.S. beef industry, bovine trichomoniasis continues to drive significant reproductive loss. Economic modeling published in the Journal of Agricultural and Applied Economics shows even modest reductions in disease prevalence can produce meaningful gains, with losses largely tied to fewer calves born and extended calving intervals. In affected herds, pregnancy rates commonly fall by 20% to 40%, and the financial impact compounds quickly over time.

At the center of it all is a consistent and often underestimated risk: the bull.

The Biology That Drives the Problem

Trichomoniasis, caused by the protozoan Tritrichomonas foetus, is a venereal disease transmitted during natural breeding. While both sexes are involved in transmission, the disease behaves very differently in cows versus bulls.

Most cows clear infection within two to four months. However, that clearance comes after early embryonic loss, often delaying conception by 30 to 90 days and stretching the calving season.

“The cow can mount a short-term immune response and clear the infection. She can eventually rebreed and carry a calf to term, but she’s going to lose that initial pregnancy that she had,” said Jennifer Koziol, associate professor of food animal medicine and surgery at the School of Veterinary Medicine at Texas Tech University on a recent episode of DocTalk .

Bulls, by contrast, create the long-term problem.

“The bull is a silent carrier because he doesn’t have any symptoms. He’s just going to spread it from female to female during breeding,” Koziol says.

A recent review published in the International Journal of Molecular Sciences explains why. The organism colonizes the preputial crypts, where immune clearance is limited. As bulls age, these crypts deepen, increasing the likelihood of persistent infection. Once infected, bulls typically remain carriers for life.

This biological mismatch is what makes control so difficult. The cow eventually clears the infection, but only after reproductive loss. The bull never clears it and continues to transmit it.

Recognize the Pattern in the Herd

Trichomoniasis rarely presents as a single obvious sign. Instead, it emerges as a pattern of reproductive inefficiency that can be easy to misinterpret early on.

“We see low pregnancy rates ... cows returning to estrus at intervals they shouldn’t, we can see abortions, ” Koziol says, discussing the big indicators that something is wrong in the herd.

These clinical signs reflect disruption during early gestation. Most losses occur within the first 60 days of pregnancy, often before confirmation, which is why the problem may go unnoticed until later in the season.

The full impact often becomes clear at pregnancy check.

“We go out and do pregnancy checks, and we’re only getting 50% to 60% conception rates. That’s a pretty terrible day when you’re just saying open, open, open,” Koziol says.

In heavily affected herds, calf crops can drop into the 50% to 70% range, well below the 85% to 95% typically expected in well-managed operations. At that point, the biological effects have already translated into economic loss.

“This is not an individual animal problem — it’s a herd-level problem. Once we find a positive, we have to start thinking about the entire bull battery and the whole herd,” Koziol says.

Epidemiologic studies, including one published in Theriogenology, show herd structure and management decisions drive disease persistence. The use of older bulls, multi-sire breeding systems and the introduction of untested animals all increase risk. Even a single infected bull can maintain transmission within a herd, particularly when multiple bulls are breeding simultaneously.

How Trich Continues to Spread

Despite long-standing awareness, trichomoniasis persists because of how easily it moves between herds and how difficult it can be to detect with absolute certainty.

“A lot of times the way a herd gets infected is if a neighbor bull breeds cows, then your bull breeds behind him and becomes positive. That’s why testing before and after the breeding season is so important,” Koziol says.

Fence-line contact, shared grazing and commingling all create opportunities for exposure. Diagnostic research, including recent work on evolving testing approaches, highlights another challenge: no single test guarantees detection. While PCR has improved sensitivity compared to traditional culture, false negatives can still occur due to sampling technique, organism load or intermittent shedding.

For that reason, Koziol suggests repeated testing should be used to improve confidence in bull status, specifically at the start and end of the breeding season. Even virgin bulls should be screened.

“We don’t trust a virgin-status bull,” Koziol warns. “When we buy a bull, we want to test him and know that he’s negative.”

No Treatment, Only Prevention

A defining limitation of trichomoniasis control is the absence of an effective treatment for bulls. Prevention depends on verification, not assumption. Bulls must be tested prior to introduction, regardless of perceived risk.

Once a bull tests positive, removal from the breeding population is the only effective option. There is no reliable method to eliminate infection.

Vaccination plays a supportive role, primarily in cows, where it can reduce the severity and duration of infection. While experimental vaccine trials in bulls have been performed, they have not yet produced a practical solution for eliminating the carrier state. As a result, vaccination should be viewed as an adjunct, not a replacement for testing and culling.

The Economics of Getting it Wrong

For producers weighing the cost of testing, the comparison is straightforward.

“The test costs about $45 to $60 depending on the state. That’s pretty economical compared to losing multiple $2,000 cows,” Koziol says.

Economic analyses reinforce this at scale. Losses are driven not only by fewer calves, but also by extended calving seasons, reduced uniformity and increased replacement pressure. Even relatively small drops in pregnancy rate can have a measurable impact on profitability, particularly in larger herds.

Where Control Succeeds or Fails

Operations that successfully control trichomoniasis tend to follow a consistent set of practices:

Test all bulls before and after each breeding season
Remove positive bulls immediately
Minimize commingling and fence-line exposure
Verify the status of all incoming breeding animals

When these steps are applied consistently, trichomoniasis becomes a manageable risk. When they are skipped, even once, the disease can establish and persist.

Trichomoniasis is not a new disease, and it is not a mysterious one. Its persistence is tied to a single, well-defined weakness in herd management.

Bulls remain the weak link because they are both the reservoir and the vector, carrying infection silently and indefinitely. The visible losses show up in the cow herd, but the source remains easy to overlook. Control depends on consistent use of the tools already available.

Trichomoniasis erodes reproductive performance quietly, one breeding at a time. In most cases, the problem begins — and continues — with the bull.

Zoetis to Acquire Neogen’s Animal Genomics Business

Mon, 02 Mar 2026 13:52:23 GMT

Today, Neogen Corporation , an innovative leader in food safety solutions, announced it has entered into a definitive agreement to sell its global genomics business to Zoetis Inc. , the world’s leading animal health company, for $160 million, subject to customary closing adjustments.

Neogen’s planned divestiture, which had been previously announced, was part of the company’s portfolio review strategy to simplify the business and focus on core strategic markets.

“Neogen’s genomics business ( GeneSeek ) has been a pioneer in advanced DNA testing for livestock and has set a high standard for innovation across the livestock sector, with globally recognized solutions spanning genomic prediction, herd improvement and data integration,” says Tom Schultz, Neogen head of commercial global genomics."We’re excited to build on that foundation in our future with Zoetis and to continue advancing tools that strengthen animal health, performance and overall profitability. Customers can expect a thoughtful transition and continued excellent service,”

According to a Zoetis release , “This acquisition aligns directly with Zoetis’ strategy to drive future livestock innovation through genomics, reinforcing its commitment to livestock producers worldwide and advancing its precision animal health portfolio. By integrating Neogen’s genomic technologies and data solutions, Zoetis is expanding its capabilities to deliver predictive insights, individualized care and greater value to customers across major livestock and companion animal species.”

Neogen’s genomics business serves customers in more than 120 countries through its five laboratories in the U.S., Brazil, Australia, China and the United Kingdom, as well as an office location in Canada. The business leverages a comprehensive genotyping platform of fixed array and sequencing technologies, as well as software solutions that empower customers to make informed and data-driven decisions. The business is a leader in U.S. beef and dairy genomics , and its cutting-edge technologies enable highly accurate, scalable genetic testing and deeper insights into animal health, productivity and sustainability.

“This transaction is part of the company’s strategic portfolio review and allows the company to accelerate de-leveraging and improve profitability going forward,” says Mike Nassif, Neogen’s chief executive officer and president. “Furthermore, this deal allows us to focus in areas where the company has the most significant competitive advantage and further leverage our core capabilities in food and animal safety. We are committed to a smooth transition for customers, employees and other stakeholders, and believe the business is well positioned to thrive under Zoetis’ ownership.”

GeneSeek has been a pioneer in advanced DNA testing for livestock and companion animal industries, leveraging a global presence to deliver highly accurate, data-driven insights that contribute to improved animal performance and health, as well as profitability, in the beef, dairy and other industries. Through the flagship Igenity and GGP portfolio and rapid turnaround times, the business offers returns-focused genomic tools and globally recognized standards in genomic prediction to accelerate herd improvement and enable genomics trait screening. Supported by the Encompass platform for genomic data integration and strategic partnerships advancing DNA-backed traceability, GeneSeek is committed to continued innovation and scientific excellence.

“We’re excited to build on our innovative genomics portfolio offerings in our future with Zoetis and to continue advancing tools that strengthen overall animal health, performance, and profitability,” Schultz says. “At Zoetis, genomics becomes a core part of a company fully dedicated to animal health. Zoetis brings deep scientific capabilities, operational scale, and a long-term commitment to genetics and data.”

Jamie Brannan, Zoetis chief commercial officer, adds, “The addition of Neogen’s genomics business strengthens our commitment to advancing animal health through innovation, data and technology. As we continue to grow our leading innovative solutions in Precision Animal Health, this acquisition brings complementary capabilities that expand predictive insights and individualized care, enabling us to deliver added value to customers. Together, we are shaping the future of animal health, empowering customers with the tools they need to support healthier animals and sustainable livestock production globally.”

The transaction is expected to close by the end of the first half of the company’s 2027 fiscal year, subject to regulatory approval and customary closing conditions. The net proceeds from the transaction are expected to be used primarily for debt reduction. The Neogen genomics business generated approximately $90 million in sales during fiscal year 2025.

“At the time of the announcement, nothing will change,” Schultz explains. “Our customers’ contacts and ordering processes remain the same — products, services and support also remain the same. Customers can expect a thoughtful transition, continued service continuity, and future benefits from Zoetis’ focus in the business. Any changes will be communicated well in advance.”

Zoetis says it is committed to a seamless integration, supporting continuity for colleagues and customers, and building on Neogen’s legacy of innovation in genomics.

Zoetis Launches First Commercial BRD Genetic Predictions to Help Build More Resilient Beef Herds

Wed, 04 Feb 2026 13:34:06 GMT

Zoetis Inc. today announced the launch of bovine respiratory disease (BRD) genetic predictions in INHERIT^® Select for commercial cow-calf operations and as an upgrade to its INHERIT Connect test for seedstock. This marks the first time that cattle producers can select replacement females and evaluate sires based on genetic predictions for BRD health and survival.

BRD costs the beef industry nearly $1 billion each year due to calf and production losses and increased treatment expenses. Until now, producers had no way to evaluate and select for the genetics that influence calf BRD health and survival after weaning.

“This is a breakthrough for the beef industry,” says Brett Bristol, head of Zoetis Precision Animal Health. “For the first time, producers can make selection and breeding decisions based on Genomic Expected Progeny Differences for BRD health and survival, in addition to production traits. Long-term, this innovation is expected to have meaningful economic impacts on commercial cow/calf producers and downstream backgrounders and feeders.”

Genetics That Compound Over Time

As the rebuilding of the U.S. cow herd begins and replacement costs are at historic highs, producers are looking for ways to build cow herds that last longer, raise healthier calves and deliver predictable value. Genetic advancement from testing and selection compounds over time; the breeding decisions made today influence future herd health and productivity.

INHERIT Select and INHERIT Connect with the BRD Upgrade include three BRD genetic predictions in the form of Genomic expected progeny differences (GEPDs):

BRD Health (BRDH) GEPD: Predicts genetic differences in the likelihood that calves (progeny) will stay healthy after weaning without requiring treatment for BRD. Higher BRDH and lower percent rank are better.
BRD Survival (BRDS) GEPD: Predicts genetic differences in the likelihood that calves (progeny) will survive from arrival for backgrounding to harvest without dying from BRD. Higher BRDS and lower percent rank are better.
$BRD Economic Index: Combines BRDH and BRDS into a single dollar value that estimates revenue impact per calf (progeny). Higher $BRD and lower rank are better.

These predictions are based on feedlot health and performance data from a commercially representative population of more than 50,000 head of cattle across North America. These phenotypes, along with continual genetic data additions, are updated weekly and included in the Zoetis Multi-Breed Genetic Evaluation.

Select Replacements That Build Healthier Calf Crops

“GEPDs for BRD and $BRD bridge an economically important gap in current beef genetic evaluations,” says Kent Andersen, Zoetis Precision Animal Health
director of beef technical services. “BRD predictions give us a way to select for post-weaning BRDH and BRDS and related economic impact that we couldn’t before. That matters when used along with predictions for maternal, feedlot, carcass and adaptability traits, and simplified via economic indexes.”

With BRD genetic predictions in INHERIT Select, commercial cow-calf producers can:

Select replacement heifers with stronger genetic potential across all major economically important traits to set the stage for healthier and more productive calf crops.
Identify and invest in genetics for greater profit potential and less health risk that compounds over time.

Using the population of more than 440,000 commercial animals tested using INHERIT^®, researchers compared the top versus bottom 25th percentile rank based on GEPDs for BRDH, BRDS and $BRD. The comparison shows progeny of the top 25th percentile that are genetically:

25% more likely to stay healthy and not require treatment for BRD from feedlot arrival to harvest
14% more likely to survive and not die from BRD from feedlot arrival to harvest
$12 per calf advantage in net return from combined genetics for BRDH and BRDS

Evaluate Bulls for BRD Health Genetics

For seedstock, the INHERIT Connect + BRD Upgrade provides a powerful way to evaluate bull batteries and potentially differentiate sale bulls based on BRD GEPDs and $BRD.

With the INHERIT Connect + BRD Upgrade, producers can:

Potentially differentiate sale bulls with BRD predictions that benefit commercial buyers and downstream backgrounders and feeders
Evaluate A.I. sires and bull batteries to benchmark genetic merit for BRD and identify favorable and unfavorable outliers
Document genetic merit for BRDH and BRDS and position future calf crops for premium prices

When comparing bulls tested using INHERIT Connect + BRD Upgrade, bulls in the top 25th percentile rank for $BRD have a $1200 predicted advantage over bulls in the bottom 25th percentile rank, assuming they sire 100 calves during their lifetime.

Producers can contact their Zoetis Genetics representative or visit beefgenetics.com to learn more and get started with testing.

How Data, Genomics and Collaboration Are Transforming Cattle Genetics and Herd Profitability

Tue, 18 Nov 2025 14:50:11 GMT

Avoiding the pitfalls of the past, Marty Ropp and his team at Allied Genetic Resources (AGR) integrate science, service and transparency to advance genetic potential across the beef supply chain.

Ropp was the featured guest in “ The Future of Beef Show ” podcast, episode 14 .

Ropp and the podcast hosts explore the evolution and future directions of genetic improvement in the beef industry. He shares his unique journey from swine to beef genetics, emphasizing the critical role that data, technology and customer collaboration play in driving progress and profitability for ranchers and the broader supply chain.

Raised in the pig genetics industry, his formative years included education at Bethel College, Kansas State University and the University of Missouri, where he earned a master’s in pig genetics. In 1998, a pivotal year for the pork industry when market collapse forced many out of business, Ropp transitioned into beef genetics, thanks in large part to Jerry Lipsey, former American Simmental Association (ASA) CEO. Ropp says his 12 years at ASA set the stage for his founding AGR in 2010.

Lessons Learned

The 1998 crisis in pork is a foundational lesson for Ropp. He describes how the industry’s failure to adopt technology, gather and apply data, and engage with customers led to widespread business failures. Many pig genetics providers focused on tradition and appearance, neglecting scientific data and market signals — ultimately opening the door for larger, technology-driven players who could deliver what the market needed.

He says this experience shaped his determination to avoid repeating those mistakes.

“This is not sustainable, and it won’t last, and then it didn’t,” Ropp explains. “And so, I’ve been trying to apply that thought process to what I do in the beef industry ever since.”

What is AGR?

AGR is a member-owned company designed to be a full-service genetic provider for the beef industry, offering services and products that help ranchers and cattle producers improve genetics, collect and apply data, and ultimately increase the profitability and value of their herds. The company combines seedstock, feeder calf marketing, genomics and data services under one umbrella, with an emphasis on actionable genetics, customer support and continuous innovation.

He explains he started AGR because he saw critical gaps in the genetics industry.

“The idea that genetics providers needed to do more than just what they were doing, which was making what they wanted to make, and marketing them as the best genetics in the world — they needed to build closer relationships with their customers, and ultimately become part of the food business, part of the supply chain,” Ropp says.

AGR’s core mission is to increase the total value across the beef industry through better genetics, rather than simply re-distributing existing value among producers and stakeholders.

“Our program is designed to add to that pie, take cost out and add income,” Ropp summarizes. “Anything like being more involved with systems farther down chain, try to get more value from the genetics that we’ve produced and our customers make — anything like that has to be in our future plan.”

Here are some key takeaways from the discussion:

1. Data and technology drive progress. The future of cattle breeding relies on rigorous genetic evaluations, genomic testing and using data to improve both profitability and sustainability for ranchers and producers.

“We 100% believe in the genetic and genetic evaluation of data and genomic evaluation — 100% use that data to prove sires move forward as fast as they can on the back end. Then the feedback has to come,” Ropp says. “That data-driven genetic improvement for the future is what we need, and that’s how we stay engaged.”

2. Customer relationships and service. AGR emphasizes close, long-term relationships with customers, helping them through customized genetic evaluation, actionable recommendations and support services extending beyond seedstock sales.

3. Value creation through data. Collecting and utilizing high-quality commercial and seedstock data is critical. However, data’s value depends on creating actionable insights that directly improve breeding decisions and market outcomes, rather than simply accumulating or selling raw data.

“The data is necessary and valuable,” Ropp says. “But again, if you can’t feed that into a system that pays for improvement down chain, then that data is only valuable from a cost reduction ... and not really from an industry participation standpoint.”

4. Genomics for all sectors. While genomics is standard among seedstock producers, new efforts like the Right Bull program are bringing actionable, simplified genomics solutions to commercial producers, even in group-managed operations.

“Investment in genomics by itself does not drive any profitability; those genomics have to be used in tools and actionable tools that you can take advantage of immediately,” he says.

For more about the Right Bull program: Avoid Costly Bull Mistakes: Genomic Solutions for Smarter Ranching

5. Feedback loops and incentives. Effective genetic improvement requires a feedback loop where improvements lead to measurable value for the commercial producer: higher calf prices better conception rates, incentivizing continued participation.

6. Industry collaboration and partnerships. AGR and its divisions actively work with both members and non-owners, as well as with technology companies, breed associations and other stakeholders to advance genetic progress across the beef industry.

Ropp sees a need for more comprehensive commercial data, better feedback loops and systems that translate genetic progress into tangible rewards for producers. He advocates continuous innovation — using new technologies, transparent service models and collaborative partnerships to ensure that genetic improvements benefit the entire industry, not just a select few.

Check out the podcast to learn more about Ropp’s strategy of fusing technology, data and expert service to deliver actionable solutions helping ranchers achieve sustainable profitability and industry resilience.

Fat Matters: How Back Fat Impacts Bull Fertility

Wed, 10 Sep 2025 18:36:03 GMT

A bull’s job is to breed cows. From a fertility standpoint, a bull should be sound and ready to go to work each breeding season.

To better understand how a bull’s condition affects his soundness, a recent research project at the University of Georgia (UGA) looked at the relationship between a bull’s subcutaneous backfat thickness and its semen quality .

“Over conditioning is very common within the seedstock world, and we’re interested in understanding to what extent that over conditioning or increased subcutaneous back fat thickness may have an influence on that bull’s fertility,” says Molly Smith, a UGA doctorate student.

She says the project included more than 700 bulls — a combination of Angus and Sim-Angus crosses from three different bull development programs. The research process included two key steps: a carcass ultrasound and a breeding soundness evaluation (BSE).

The study categorized bulls into three groups based on their subcutaneous backfat thickness, using 10% and 20% thresholds.

When examining semen characteristics, Smith says they found some intriguing results.

“We saw no differences in the amount of motility, but we did see differences in morphology,” Smith explains.

Morphology refers to the shape, size and structure of the sperm. Sperm motility is how it moves.

Specifically, bulls in the top fat thickness categories showed concerning semen quality characteristics.

“Those bulls that were in the top threshold actually had a less percent, a less amount of normal sperm cells and a greater amount of primary and secondary abnormalities,” Smith says.

BSE Impact

Pedro Fontes, UGA associate professor, recently visited with Smith about her project during a “UGA Beef Tips” podcast .

He asked Smith if the backfat affected the bull’s ability to pass the BSE.

Smith says, “Bulls that have a greater than about 0.5" of subcutaneous back fat thickness had a greater probability to fail their breeding soundness evaluation.”

Quantifying this, she adds, “10% of them failed their breeding soundness evaluation, which is greater than two times the bulls that were in our other two categories.”

Fontes clarifies the failures were specifically related to semen quality, excluding other potential reasons for failing a BSE.

“Most of the issues that you (Smith) observed were associated with morphology and non-motility. So those cells are moving well, but they look different,” Fontes says.

Performance and ADG

When evaluating performance or average daily gain (ADG), Smith reports there was no change between bull groups.

“There actually were no differences between our categories of top, middle and bottom bulls, our top bulls were not gaining any more than our middle and bottom bulls were, so they were all kind of following the same trend,” Smith reports.

Fontes interprets this finding as significant, suggesting that “it’s not a matter of allowing those bulls to express their genetic potential for growth” but rather about understanding fat deposition.

Smith agrees, saying, “It’s about essentially where that fat deposition occurs, and that’s how it matters.”

While producers might worry about restricting bull growth, the research suggests that careful monitoring of fat distribution is more important than preventing weight gain.

Fontes summarizes the key takeaway from the research is the ability of bulls to pass a BSE appears more related to body condition score and over-conditioning rather than their overall growth potential. Excessive back fat can negatively impact a bull’s reproductive potential, even if it doesn’t affect its growth performance.

Your Next Read: Wanted: Bulls Ready to Work

Strategies to Improve Pregnancy Rates in Cow Herds

Thu, 28 Aug 2025 14:32:25 GMT

For many producers and veterinarians, it’s time to line up PG and ultrasound appointments to establish a pregnancy rate and sort off open cows. It can be a nerve-wracking day until it’s over — and even then ranchers may not be entirely satisfied with the outcome.

So, what can ranchers do if they aren’t satisfied with their herd’s pregnancy rates?

It’s beneficial to look at both an industry average and a herd average in these instances.

“If you have a 60 to 80 day breeding season and are over 90% for pregnancy rate, you are doing pretty well, according to previous North Dakota surveys,” says Lacey Quail, North Dakota State University extension livestock management specialist. “If you have a shorter breeding season, you can expect that percentage to be a little lower.”

Next, take a look at your herd records from previous years.

“If you get your PG or ultrasound results and aren’t happy, it implies you have previous records to compare it to,” Quail says. “We need to keep herd records so we can dig out something that might go under the radar and potentially cause profit loss.”

Fertility is multifactorial, which can sometimes make it challenging to pinpoint one specific cause.

She recommends producers start by asking themselves a series of questions to start narrowing down what may have caused lower pregnancy rates and where the problem occurred.

Several management questions producers can ask themselves to start to tease out the potential cause of lower pregnancy rates are:

Did you see cows cycling?
Did you see bulls mounting and breeding?
Did you see breeding activity at the beginning or end of the season?
Were the majority of open cows in one pasture or management group?
Are some of the open cows thinner than the rest of the group?
Were the majority of open cows of a certain age?
Did you experience a heat spell or other potential stressor?

Quail says, “Fertility is like a domino train. You are waiting for the last domino to fall, but the train may have fallen off track a long time ago in a different room.”

Once you answer the above questions, be mindful of the following missed opportunities.

“On the bull side, make sure you are having full breeding soundness exams completed by a veterinarian and take into account social hierarchy when putting together breeding groups,” Quail says.

After that, it’s important to remember breeding activity.

“A big missed opportunity is not taking the time to observe breeding behavior in your herd,” Quail says. “We want to evaluate if cows are cycling, and if bulls have the libido to seek, mount and breed. Noticing issues early can save a great deal of loss.”

Don’t just stop at noting activity in general. When did the activity happen?

“Take a closer look at when cows are getting pregnant, and not just if they are getting pregnant,” Quail says. “This can have a big impact on overall productivity and profitability.”

Nutrition also can’t be overlooked.

She says, “In many cases, cows calving early might reach peak lactation and breeding season before growing forages can support all their nutrient requirements. Keeping females in adequate body condition going into and out of the breeding season is going to go a long way toward overall pregnancy rate.”

Environmental stressors can’t entirely be avoided, but they can be mitigated.

“Another missed opportunity is fine tuning environments to reduce stress,” Quail says. “We can’t control the heat, but we can control to some degree how far cows and bulls have to walk to access water.”

Ranchers shouldn’t feel like they have to go through this process alone. They can reach out to specialists, veterinarians and their nutritionists for help.

“Consulting with a veterinarian regardless of your pregnancy rate is a good thing to do,” Quail says. “Some records to be aware of and share with your vet are differences in pregnancy rate and calving rate as well as any co-mingling with neighboring cattle.”

May your pregnancy rates be favorable this fall. But if not, remember to start with herd records and basic questions to help get to the cause.

You can listen to the full conversation on the Casual Cattle Conversations podcast .

Why Bull Rest Matters: Time to Prepare for the Next Breeding Season

Thu, 14 Aug 2025 14:03:32 GMT

While spring breeding season is wrapping up, and bulls are pulled from pastures it’s not time to ignore the key to your breeding program.

Kansas State University veterinarians Brad White and Todd Gunderson, and beef cattle nutritionist Phillip Lancaster say rest and proper nutrition are essential for helping bulls recover and prepare for the next breeding season.

During a recent “ BCI Cattle Chat ” podcast, the experts discussed the importance of a comprehensive approach to bull management.

“A bull may lose anywhere from 100 lb. to 200 lb. of bodyweight during a breeding season,” Gunderson says. “He’s going to need at least a couple of months to recover body condition and complete spermatogenesis (a process of sperm cell development).”

The experts recommended an approach to bull management that considers:

Reproductive health assessment
Gunderson says simply moving a bull from one breeding pasture to another without proper preparation could compromise his performance.
A key recommendation was conducting a breeding soundness exam before the next breeding season. While a previous exam might have shown positive results, the bull’s reproductive health can change significantly during a breeding season. Sperm structure and motility can develop defects that might impact fertility. Therefore, Gunderson suggested reevaluating the bull’s reproductive health to ensure optimal breeding potential.
Nutritional supplementation
The nutritional strategy varies depending on the forage environment. White highlights the importance of proactive management. Producers must anticipate nutritional needs and supplement accordingly considering the specific forage resources available.
Body condition monitoring
Simply monitoring body condition score is insufficient, as it represents a lagging indicator.
“We typically want bulls in a body condition score of 6 when turning them out for breeding,” Lancaster adds. “If he’s losing 100 lb. to 200 lb., he’ll likely drop to a body condition score of 5, (so) producers need to plan supplement strategies based on their forage resources.”
Forage resource evaluation
The experts emphasize bulls require strategic nutritional support, whether on warm- or cool-season grasses, to ensure optimal fertility and performance in subsequent breeding seasons.
They add each operation looks different based on forage resources and other regional conditions, but it’s important to care for bulls even when they are not covering cows.

The discussion underscored several critical management principles:
- Biological recovery time is essential for bull fertility
- Reproductive health should be professionally assessed periodically
- Nutritional strategies must be tailored to specific environmental conditions
- Proactive management prevents potential breeding performance issues

To learn more about bull management practices, preweaning calf management and preparing for fall processing, listen to the full episode of “Cattle Chat” online.

Your Next Read: Is It Time to Pull Bulls?

There’s a Lot of Info in That Little TSU

Tue, 29 Jul 2025 17:06:26 GMT

“The sky’s the limit if you have that sample,” says Jim Butcher, a Simmental seedstock producer from Lewistown, Mont.

He’s talking about all the things you can learn about the genetic potential of your cattle that is contained in a tissue sampling unit (TSU). The genomic information you get from each sample can, collectively and individually, help you more quickly move your herd’s genetic progress forward in an intentional, science-assisted direction.

There’s lots of info in that little vial.

(Allflex)

For commercial cow-calf producers, submitting the DNA sample in a TSU will return a scoresheet on each animal ‘s genetic merit for different indexes and specific traits, says Leoma Donsbach, owner and founder of Data Genie, LLC.

She calls herself a data accountant, helping customers attach the data on their operation to their record-keeping system. She says almost all her customers use TSUs to collect DNA and obtain genomic data.

Genomics are becoming more and more popular with commercial beef producers, she says.

“For replacement females, the ability to have a snapshot of that female’s genetic potential leads to increased confidence in keeping that heifer. You can say, ‘This heifer is more likely to be here until age six or seven by looking at her stayability metrics.’”

Say, for example, you’ve done your visual appraisal and picked 50 heifers as potential replacements, but you only need to keep 40. Visually, those heifers are very similar. But genetically, they could be very different, depending on what genes they received from their parents.

That’s where the TSUs and the genomic data they provide come in. First, test all 50 replacement candidates.

“Then breed them and find out which ones are bred,” she says. Even if everything went right, that still leaves some extras. “You can go back and use the genomic data to select the traits you want and/or use a maternal or terminal index to make those final decisions. You use it like comparing genomically enhanced EPDs when buying bulls.”

Beyond replacement selection, you can extrapolate the DNA data on your heifers when marketing your steers, she says. “On average, your steers will have similar genetics to your heifers. That information may add to their sale price.”

Then There Are The Bulls

Just like heifers, bulls can be full siblings and still be remarkably different in their genetic makeup.

“We’re great phenotype collectors of birth weights, weaning weights, all that,” Butcher says. “But you really don’t know what you have until you know what genes that particular animal picked up.”

When seedstock producers send in a TSU, they get back genomically enhanced EPDs. That, Butcher says, allows him to supply more accurate information about young bulls for his customers and help them make the best bull-buying decisions they can within their budget.

Indeed, not every bull is suited for every ranch. Studying the genomically enhanced EPDs gives you greater confidence in the true genetic potential of young bulls.

“You lessen the probabilities that you’re buying an animal that won’t help you move your program forward,” Butcher says.

Your Next Read: Building the Next Generation Cow Herd Using Genomic Testing

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.

Your Next Read: 5 Strategies to Help Cattle Cope with Heat

Is That Cattle Herpes or a Rash?

Mon, 02 Jun 2025 14:44:22 GMT

A cow with signs of a urinary tract infection was treated by a veterinarian and then later developed bumps on her vulva. The veterinarian diagnosed the cow with infectious bovine rhinotracheitis (IBR). Also known as “red nose,” IBR is a contagious viral disease caused by the bovine herpesvirus type 1 (BHV-1).

Kansas State University’s Beef Cattle Institute experts discussed the diagnosis and cattle herpes during a recent “ Cattle Chat ” podcast.

K-State veterinarian Bob Larson says herpes is a common and highly contagious virus in cattle. The virus typically creates vesicles (small bumps) in two primary locations — the respiratory tract and the reproductive tract. These vesicles appear on areas such as the nose, penis, prepuce and vulva.

While the virus is widespread, clinical symptoms are relatively rare due to existing immunity from vaccines and natural exposure. However, when symptoms do appear, they can be significant. The most concerning potential complication is abortion, which can occur weeks after the initial infection.

Brian Lubbers, K-State veterinarian, says like human herpes, the cattle herpes virus can become dormant in nerve roots after initial infection. This means the virus can remain inactive and then reactivate under stress, similar to how humans experience cold sore recurrences.

The discussion highlighted how herpes can enter a herd, particularly in closed herds. In this case, a recently purchased bull likely introduced the virus. Most cattle herds already have animals that are carriers, making transmission relatively common.

Diagnosing IBR
The K-State veterinarians emphasized the importance of proper veterinary diagnosis. While the veterinarian suspected herpes in the example mentioned, Lubbers notes the need to rule out other conditions like trichomoniasis, which can cause similar reproductive tract symptoms.

He says the key diagnostic considerations include:

Examine the location and nature of bumps (external versus internal reproductive tract)
Check for additional symptoms like discharge
Conduct appropriate veterinary testing to confirm the specific disease

Management Strategies

The discussion included several management recommendations.

“Our vaccines for IBR herpes virus are pretty effective,” Larson says. “So, a lot of cattle have decent immunity to herpes virus, either from natural exposure or vaccines, or probably a little bit of both.”

If you suspect IBR after vaccination, Larson suggests reviewing and potentially updating current vaccination strategies.

“Recheck your vaccine protocol, make sure that you’re using the vaccines appropriately,” he explains.

He adds vaccinating during an active outbreak might not change the immediate outcome.

If a producer suspects IBR, they should closely watch the herd for potential abortion events in the weeks following the initial infection.

Selling Considerations

The experts addressed the concern about selling an infected cow.

“Lots of herpes carriers are getting sold,” Lubbers notes.

The K-State experts encourage producers not to sell one that is clinically ill and to consult sale barn regulations regarding disease-specific selling restrictions.

Proper understanding, veterinary guidance and proactive management can help producers effectively navigate cattle herpes.

Your Next Read: Five Pre-Pasture Turnout Tips

Can We Get Calving Ease Without Sacrificing Performance?

Thu, 01 May 2025 15:53:27 GMT

Sire selection for natural service or artificial insemination (AI) is critical. Over time, 90% of genetic change is the result of sire selection. Your bull (or bulls) contribute more to the genetic makeup of your herd in a calving season than a cow does in her lifetime.

Effective sire selection should be based on genetic values in the form of EPDs or expected progeny differences . Selection on EPDs is 7 to 9 times more effective than selection based on individual performance data, within herd ratios or performance testing because all this information (plus more) is taken into consideration in calculating EPDs.

Selecting genetically superior sires is the fastest approach to herd improvement and bottom-line profitability when you select genetic superiority that matches your management, production and marketing system.

If you are identifying bulls to breed heifers this spring and calving ease is a priority, current sexing technology can work to your advantage. Research shows that heifer calves are, on average, approximately 5 lb. lighter than bull calves at birth. The lighter birth weights will equate to less likelihood of dystocia.

If sexed heifer semen is your preferred path to calving ease, expect to pay a little more (approximately $20/straw) per unit than typical of conventional semen. As well, timing of AI should also be delayed by six to 12 hours if using sexed semen.

Charting the genetic trend of beef breeds indicates purebred cattle breeders have been very successful over the past 30 years of applying selection pressure to maintain calving ease while improving the additive genetic merit for weaning and yearling weight performance. What we commonly refer to as “curve benders” are easier to find than ever, especially when sorting through bull stud offerings of potential AI sires.

So to answer the questions in the title, yes it is possible. With ample calving ease sires available in the current marketplace, you should still be able to identify sires that give you the growth, carcass merit or levels of maternal performance you seek to improve your operation’s bottomline.

Mark Johnson, Oklahoma State University Extension beef cattle breeding specialist, discusses the changes occurring in the cattle industry.

Your Next Read: Accurately Comparing Bulls: Updated Adjustment Factors Released

Body Condition Scoring Bulls: Now is the Time to Make Sure Bulls Are Ready for Turnout

Mon, 31 Mar 2025 16:55:46 GMT

As cattle producers prepare for pasture turnout and breeding season, it is important to evaluate bulls and make sure they are ready to go to work. Along with breeding soundness exams to ensure a bull is fertile and ready for his job, another tool for producers to use is body condition scores (BCS) to make sure the bull is in good condition — not too skinny or too fat.

Phillip Lancaster, Kansas State University beef cattle nutritionist, and Brad White, K-State veterinarian, offer advice on how to assess bull body condition .

According to Lancaster, producers can use the same scoring system for bulls as they do females.

“We use the same system for all classes of cattle, 1 to 9 scale ,” Lancaster explains. “That scale is related to body fat composition.”

Bulls should be evaluated like cows: observing the amount of fat the bull is carrying on his back, ribs and hooks and pins.

“As an animal moves from one point on the body condition score to another, they are either gaining or losing body fat and potentially muscle mass,” Lancaster says. “If they start with a lower body condition score and lose weight, that change will lead to a decline in more muscle mass than fat. Conversely, if they are at the other end of the scale, the animal will lose more fat than muscle mass.”

Bulls require more weight change to move between BCS points due to their larger size.

“A rule of thumb,” Lancaster says, “is about 7% of their normal weight at a body condition score of 5 is what they should gain or lose.”

He gave the example of a 2,000-lb. bull that had a weight change of 150 lb. leading to a score change. In contrast, Lancaster says, a cow will shift a body condition score at 100 lb. due to the differences in size and muscle mass.

Monitoring BCS has special implications for yearling bulls who are still growing, White explains.

“Yearling bulls typically have a different body condition than mature bulls at pasture turnout, and the goal is to have the bulls in a positive energy balance heading into breeding season so that they can maintain it through the season,” he says.

Monitoring body condition scores is important year round. White reminds producers the goal should be to keep bulls in a positive energy balance during breeding season, which allows for fat deposition.

White also gave an example that for a cow to improve a body condition score the standard thought is to increase body weight 100 lb. At 2 lb. per day gain, it takes a female 50 days. In comparison, a bull will need longer, so it is important to be proactive.

“Now is the time to make sure the bulls are in the right body condition so that there is time for them to gain weight a head of turnout,” White says.

Your next read: Wanted: Bulls Ready to Work

Lidocaine Infused Bands Minimize Castration Discomfort for Young Calves

Mon, 25 Nov 2024 23:37:43 GMT

As consumer concern for animal rearing practices rises, and industry awareness of animal welfare increases at the same time, food animal rearing practices are changing in step.

One of those practices: castration, a necessary yet painful rite of passage for every male animal destined for the beef market. A recent study at Kansas State University – presented at the American Association of Bovine Practitioners Conference in Columbus, Ohio -- demonstrated how lidocaine-infused castration bands can help calves transition through the castration phase more smoothly and comfortably.

In the study, 26 beef-cross calves under two weeks of age were banded with either the lidocaine-infused band, or a conventional castration band. Calves were individually housed for close observation, and followed via 24/7 video surveillance for 42 days.

Among the results, researchers found:

· The calves treated with the lidocaine-infused bands had significantly more bouts of lying, and more total lying time, than those treated with conventional bands.

· The greatest disparity in lying time occurred between days 21 and 35, which is significant because that is the typical time when bands start cutting through the tissue. “It is great to see the lidocaine-banded calves were comfortable lying down at a time that we often say is the chronic part of the pain related to castration,” noted Eduarda Bortoluzzi, DVM, and assistant professor of animal welfare in the Department of Anatomy and Physiology, Kansas State University.

· While weight loss would be expected immediately after castration, calves receiving the treated bands gained a bit of weight the first week after castration, while those with conventional bands lost weight during the same time period – an indication that the lidocaine-banded calves returned to appetite more quickly.

· At the end of the study, the final bodyweight was an average of more than 3 pounds higher for the calves receiving the lidocaine-treated bands compared to those receiving conventional bands.

“In addition to weight gain, it’s also about doing the right thing for our animals and providing some type of analgesic relief during castration because we know it’s painful,” declared Bortoluzzi. “I would use it to decrease their stress during this period. We now have a type of analgesic that was not available before.”

In other news from Bovine Veterinarian:
New Veterinary Teaching And Research Hospital To Break Ground
Does Your Veterinary Business Culture Need To Change?

BSEs can Add Dollars to Producer Pockets, Thanks to Improved Calf Weaning Weights

Mon, 18 Mar 2024 19:13:59 GMT

Calves are worth their weight in gold these days. That’s a bit of an exaggeration but not much of one. Calf values are a big reason why thorough bull breeding soundness examinations (BSE) are so important.

If producers turn out a subfertile bull this spring, it means some cows in the herd won’t get bred. A greater problem on farms and ranches today: many cows won’t get bred in a timely manner -- during the first third of the breeding season.

Those problems are costly to cow/calf producers, reports Dr. Chance Armstrong, Auburn University College of Veterinary Medicine.

“You’re losing 50 to 60 pounds of weaning weight every 21 days when the bull’s not efficient,” says Armstrong, who addresses the topic of BSEs, in partnership with Dr. Jennifer Koziol at Texas Tech School of Veterinary Medicine.

Remove Subfertile Bulls From The Herd:

Koziol and Armstrong want producers and veterinarians to focus on identifying subfertile bulls and removing them from the beef herd.

The best way to do that is with a breeding soundness examination, which is a four-part process involving: a physical examination, motility, scrotal circumference and morphology.

It’s important to understand the value of assessing morphology. Veterinarians are able to evaluate sperm shape, the various elements that make up the sperm and how it moves. Morphology involves more than just looking at sperm to see if it “wiggles.”

BSEs Are Good Insurance For Cow/Calf Producers:

Armstrong says the cost of a BSE offered by a bovine veterinarian in most parts of the country is usually under $100 per bull. That’s good insurance, especially given the alternative. Not having a BSE performed by a qualified veterinarian can cost a cow/calf producer thousands of dollars.

Below are calculations from two scenarios Armstrong shared with producers at the 2024 National Cattlemen’s Beef Association annual conference. The numbers are based on two 100-cow herds, one serviced by a fertile bull and the other by a subfertile bull.

When the final numbers were tallied, the herd serviced by the fertile bull delivered a whopping net advantage of $22,590.62 over the subfertile bull.

At least three things contributed to those additional dollars: more cows were bred, the cows were bred in a more timely manner so calves were born earlier in the season, the fertile bull’s offspring were able to gain more pounds by weaning time.

Calving Timing Impact
1st third of calving season: 226 days x 2.1 #/day + 75# = 549.6#
2nd third of calving season: 205 days x 2.1 #/day + 75# = 505.5#
3rd third of calving season: 184 days x 2.1#/day + 75# = 461.4#

Pounds of Calf
Fertile Bull (94 cows bred) Subfertile Bull (78 cows bred)
60 head x 549.6 lb. = 32,976 lb. 40 head x 549.6 lb. = 21,984 lb.
24 head x 505.5 lb. = 12,132 lb. 24 head x 505.5 lb. = 12,132 lb.
10 head x 461.4 lb. = 4,614 lb. 14 head x 461.4 lb. = 6,460 lb.
Total lb. = 49,722 lb. Total lb. = 40,576. lb.

Dollars Per 100 Cows
Fertile Bull Subfertile Bull
49,722 lb. @ $2.47/lb. = $122,813.34 40,576 lb. @ $2.47/lb. = $100,222.72

Net advantage of the fertile bull: $22,590.62

For more information on BSEs, check out these additional articles:

Veterinarians Raise The Bar For Bull Breeding Soundness

Cattle Chat: Evaluating bulls for breeding soundness

Schedule Breeding Soundness Exams Before Turnout

Breeding Soundness Exam: A risk management tool

The Importance of Breeding Soundness Exams

BSEs help Veterinarians Provide a $7 ROI for every $1 Cow-Calf Producers Invest, on Average

Fri, 08 Mar 2024 17:41:18 GMT

As a bovine veterinarian, you have many irons in the fire at any given time during the year. That fact alone may cause you to second guess whether emphasizing breeding soundness exams (BSEs) before bull turnout this spring is worth your time and effort. The short answer to that question is, yes, they are, according to Chance Armstrong, DVM, MS, DACT, Auburn University College of Veterinary Medicine.

Armstrong likes to tell producers and veterinarians that BSEs are vital to conduct 30 to 60 days ahead of turnout for every bull, every year.

“It’s one of the best insurance policies your beef producers can have,” he says. “It helps them and you know their bull will get the job done and done well.”

A Snapshot In Time

Illness, effects from a harsh winter, inadequate nutrition and a variety of other factors can render a great bull from last season subfertile this spring. Or, you could simply be dealing with a young bull that needs more time to mature.

“I am an equal opportunity evaluator of bulls,” Armstrong says. “I evaluate them the same way every time so human elements don’t come into play if they fail. As veterinarians, that consistency is important to maintain.”

A consistent BSE strategy will help you do the best job of identifying subfertile bulls, according to Jennifer H. Koziol, DVM, MS, DACT, Texas Tech University School of Veterinary Medicine.

“We need to identify those subfertile bulls, because they can really hurt the producer’s bottom line,” Koziol says.

“With a subfertile bull what happens is the cow’s cycling, and the bull should have got her pregnant but missed her,” Armstrong adds. “Research shows us we can lose 50 to 60 pounds of weaning weight per 21-day cycle. We simply can’t afford that inefficiency in the beef industry.”

Show And Tell
For a bull to be deemed a “satisfactory potential breeder,” the Society for Theriogenology maintains that 70% morphologically normal sperm is the standard. Along with that, the bull must have a minimum of 30% progressively motile cells.

“Multiple studies have shown us that about 80% of the bulls that fail breeding soundness exams do so because of poor sperm morphology,” says Koziol.

Armstrong adds that beef producers benefit from knowing the quality of their bull’s sperm. Factors like nuclear vacuoles and pyriform heads can quickly impact fertility of the ejaculate.

“Information on the morphology is an important point of differentiation between you, the veterinarian, and what a layman is able to tell the producer,” Armstrong says. “We need to use that information to our advantage and to educate our producers.”

A good electroejaculator and a high-quality microscope can help the process along. While a phase-contrast microscope can make it easier to see certain sperm morphology defects, Koziol says a good brightfield microscope can get the job done just as well.

“Diadem defects (a sperm morphology abnormality) are a great way to know if your microscope is good enough or not,” she says. “If you can easily see diadem defects and recognize them on sperm morphology slides, then your microscope is good. If you never see them during an entire bull-checking season, then perhaps you should think about investing in a new microscope.”

In addition, Koziol says camera systems for microscopes have become more economical and can transmit the microscope image to a TV screen or monitor.

“This is a great way to add value to our examinations, as it takes the mystery away from what we are seeing in the microscope,” she says, noting that bull owners can quickly learn what normal and grossly abnormal look like.

“In my experience, owners who have observed the results will often call a bull unsatisfactory, even before I can finish counting 100 cells,” she says. “It makes my life easier when I can show an owner why their bull is not going to cut the mustard this breeding season.”

No Short Cuts To Excellence
Armstrong says a complete physical exam helps provide certainty that you have done due diligence for the bull and the producer.

The four key aspects of a complete breeding soundness exam are:
1. Physical Examination
2. Measuring Scrotal Size
3. Evaluation of Semen Morphology
4. Evaluation of Semen Motility

“When a bull passes all four parts of the exam, he is set up for reproductive excellence, meaning he should achieve a 60% to 65% conception rate every 21 days on those cycling cows that are healthy,” Armstrong says. “At the end of three cycles, the bull can have 90% to 95% of those cows bred, with most of them delivering in the front end of the calving season.”

“We actually make the operation money with the BSEs,” he adds. “The research shows us producers get about $7 for every $1 they invest in the process, and that’s a great return-on-investment.”

Society For Theriogenology Manual Updates
The Society for Theriogenology updated its recommendations regarding BSEs in 2018. Three of the Breeding Soundness Examination of Bulls manual changes are:

With respect to morphology, the abaxial tail implantation and the distal droplet are no longer to be categorized as abnormalities.
Also, the classification scheme designating sperm morphology abnormalities as Primary or Secondary was discontinued and descriptors with respect to location (head, midpiece, and tail) are currently utilized.
With respect to motility, assessment should be by evaluation of progressive motility; the minimum standard (30% progressively motile) however was not changed.

Winter Weather Challenges for Bulls Can Affect Breeding Season

Wed, 24 Jan 2024 15:26:56 GMT

Livestock producers know winter can be a challenge for their cowherds, and Karla Wilke, Nebraska Extension cow-calf/stocker specialist, reminds them not to forget about their bulls in their winter management plans.

“Bulls are one of our bigger investments in the cow herd, and 90 percent of the cows are still impregnated through natural service with a bull rather than artificial insemination,” Wilke said. “So, they also require year-round maintenance.”

While most cows are in larger groups, bulls tend to be in small groups, resulting in more exposure to the elements. Keeping them protected from the elements is crucial. A bull’s testicles can get frostbite, which could decrease semen production and quality, making it hard to pass their breeding soundness exams. Wilke suggests windbreaks and some bedding of poorer quality feed bales or corn stalk residue bales to protect and maintain the bull. Winter weather can also create scenarios where bulls can be injured, such as on ice. If it doesn’t recover by the breeding season, it can create a loss, having to be sold or culled in the spring.

Winter is not the only season a bull can be at risk. Especially for young bulls, where they can lose weight with low-quality forages in drought. A young bull can lose one to two points on a body condition score of one to nine during the breeding season. Maintaining a body condition score of five to six in winter will result in higher quality semen than when bulls have a body condition score of four.

A livestock producer will also need more bulls for the breeding season if all their bulls are young. “A young bull, who is typically 12-16 months old, can breed 10-15 cows. A mature bull of 30 months or more can breed 25-30,” Wilke said. When mixing young and older bulls, keep an eye on the older bull. Older, larger bulls can injure younger bulls when fighting for dominance.

“It’s really important to have yearly breeding soundness exams done on all bulls,” she said. When a bull breeder sells a new yearling, that bull will have had to pass to go through sale. Producers will want to make sure older bulls continue to get soundness exams. A dominant bull who cannot pass a breeding soundness exam and prevents younger bulls from having access to the cows can result in cows that do not get bred or get bred late in the breeding season. It takes a bull two months to produce semen. Again younger bulls are still growing and will sometimes fall apart in the winter if their nutritional needs are not met.

What's A Good Bull Worth?

Wed, 27 Dec 2023 13:54:56 GMT

The question that has been asked forever, or at least as long as we have been breeding cattle with a notion of trying to make the next generation better. It is a classic and timeless question. It is an important question. At this time of year, when many bulls are being marketed and we are planning ahead for spring breeding season, it is the question that is asked a lot! Perhaps it is all the above because it is so challenging to answer.

The Answer

I remember first hearing the answer nearly 40 years ago as a student at OSU. “A good bull is worth the value of five calves he sires”. I’ve heard that answer again many times over the years. I believe it is a good answer and a good rule of thumb to follow, the problem is it doesn’t exactly narrow down the range. If we do a little math, this answer may in fact lead to more questions. Such as ………

When are we marketing our Calves? What is their Value?

According to the most recent USDA Cattle Market Report:

500 lb. weaned steer calves (Large, 1) are worth about $2.00/lb. for a value of $1,000 per head. Therefore, if my future marketing plan is to sell weaned steers, $1,000 x 5 = $5,000 is the answer.

875 lb. yearling steers (Large, 1) are worth about $1.57/lb. for a value of $1,374 per head. Therefore, if my future marketing plan is to sell yearling steers, $1,374 x 5 = $6,869 is the answer.

920 lb. beef carcasses are worth $2.26/lb. for a value of $2,079 each. Therefore, if my future marketing plan is to retain ownership through finishing and sell fed cattle on a carcass value basis, $2,079 x 5 = $10,395 is the answer.

So, in the current market, a good bull is worth somewhere between $5,000 - $10,395 to a commercial cattle operation. Where exactly in that range depends on your marketing plan and the market conditions at that time. Not an exact number because there are “many layers to this onion”. One important point illustrated here is that the longer you will own the offspring before marketing, the greater the amount you can afford to pay. Retained ownership gives you more time and opportunity to capture the value of your investment in genetics.

And we haven’t even considered the value added to replacement females if we select daughters as our next generation of cows. More on that next week when we discuss looking at your unique operation to shed more light on this question and determine where to apply selection pressure. Until then, keep the following chart in mind as another way to evaluate ownership cost of bulls on a per cow or annual basis.

(Farm Journal)

Winter Management Strategies of Herd Bulls

Tue, 31 Oct 2023 14:16:22 GMT

Bulls are often a part of the cow herd that slips through the cracks during the winter months as breeding seasons come to a close. All things considered, the working season for a herd bull is relatively short, with an active breeding season of 60 to 90 days for most producers.

When winter weather moves in, and the bulls are pulled from the cow herd, it is imperative to manage herd bulls properly to prevent frostbite of the testes and properly manage body condition score before the next breeding season. Bull management strategies during the winter months can impact a bull’s performance in the upcoming breeding season.

Frostbite
Frostbite presents as a scab, discoloration, and/or sloughing of the bull’s scrotum. These tissue damages limit or prevent the ability for a bull to regulate testis temperature. This is caused by the inhibition of the raising and lowering of the testes that occurs naturally. Come breeding season, this can result in a decrease in fertility.

Dry areas to lay are important to consider when wintering bulls. These areas can be achieved by providing bedding or areas within a pasture that provide adequate cover from wind and snow. Wet and cold conditions increase the risk of frostbite. Table 1 illustrates the effect of frostbite severity of semen quality.

(Farm Journal)

Nutrition
Nutrition of bulls depends on a variety of factors, including age and weight loss that occurred over the breeding season. Mature bulls that are in good condition following breeding season can be managed on pasture or an all-forage diet without supplementation, as long as the forage contains 8 to 10 percent crude protein and is available daily at 2 percent of body weight.

Yearling bulls following their first breeding season are still growing and require more energy and nutrients regardless of condition when compared to mature bulls. A ration developed for young bulls should target an average daily gain of 1.5 to 2.0 pounds dependent on weight lost during the breeding season. A diet crude protein of 10 to 11 percent should be targeted for young bulls. Regardless of diet available and the age of the bull, a good vitamin and mineral program should be followed.

Body Condition Score
At the beginning of the breeding season, ideally bulls should have a body condition score (abbreviated as BCS) of 6. This BCS allows for bulls to lose some weight during the breeding season without negatively impacting sperm quality. It is common for bulls to lose 100 to 200 pounds over the breeding season.

In contrast, over-conditioned bulls are not able to efficiently do their job of breeding cows. At higher body condition scores, fat deposition within the scrotum increases, resulting in poorer thermoregulation of the testes. This reduction in temperature regulation decreases overall sperm quality. To prevent last-minute efforts to improve condition score, producers should evaluate their bull’s BCS 90 to 120 days prior to turnout to provide adequate time to improve or decrease body condition if necessary.

Housing and Exercise
Bulls should be housed in a pen large enough to allow for adequate exercise. Additionally, a large pen allows for the less-dominant bulls to move away from more-dominant bulls. Bulls will fight to determine social ranking; however, providing space for animals to get away from each other may reduce injuries. If bulls are being fed at the same time, 24 to 30 inches of feeder space should be provided per head to allow access for all animals and lessen incidences of fighting.

It is important to provide room for exercise to keep bulls in shape for the next breeding season. If proper exercise is not permitted, bulls can lose their endurance and struggle to keep up in the beginning of the breeding season, resulting in a potential reduction of cows bred during the beginning of the season. Exercise can be encouraged by placing feed and water on opposite ends of the pasture. Ideally, the winter housing area would be located away from cows to allow bulls to fully focus on eating and other behaviors rather than breeding cows.

Management of a New Yearling Bull Sets the Stage for Performance Success

Thu, 19 Oct 2023 21:24:28 GMT

Young beef bulls new to their jobs on the farm or ranch often need extra time and attention to get acclimated to their environment and roles. During a recent Beef Cattle Institute podcast, livestock experts at Kansas State University addressed how to best manage a young bull, thanks to a cattleman who submitted this question: “I just purchased a relatively expensive yearling bull and am preparing to turn him out with my herd. What are your tips to making sure we have a successful year with this bull?”

“I’m going to say really pay attention to him,” advised Robert (Bob) Larson, DVM and professor of production medicine at the university.

“This is not a proven bull, so make sure you consider all things about his health. Body condition score, feet and legs soundness – all the types of things that can cause a bull to have health problems and structural problems,” Larson said. “Monitor all of that pretty closely because he’s young, and he’s just getting to know his way around the operation.”

Turnout duration is an important management decision. Young bulls tend to run themselves a bit ragged, and producers need to take that into consideration in their management, according to Bob Weaber, Extension beef specialist at K-State.

“We can control that by not leaving him out with the cows for the entire breeding season,” Weaber said.

The benefits of not pushing a young bull to perform throughout a long breeding season are at least two-fold. The first is the producer is better able to maintain that animal’s well-being. Second, the producer can minimize the potential for having a bunch of open cows, because the yearling bull was new to his job.

Weaber said he would use the yearling bull for about half the breeding season and then bring in another bull to finish the season.

“I’d turn out multiple bulls, though maybe not at the same time so you can minimize the potential for social dominance problems,” Weaber said. “In a multi-bull pasture a concern that arises is injury due to the bulls fighting and aggression.”

Weaber said when the young bull is pulled out of the herd, it’s important for producers to have the ability to place him somewhere else on the farm or ranch, so he’s not over-worked or in competition with other working bulls.

Brad White, production medicine director for the Beef Cattle Institute and host of the podcast, said he would assume the yearling bull in question had had a breeding soundness examination prior to being purchased. He asked what Weaber and Larson would watch for during the breeding season, specifically related to the bull’s ability to breed.

Larson reiterated that regardless of age and experience, some of the main things to evaluate during the season are a bull’s feet and legs.

“Foot rot, injury, anything that affects mobility is going to affect his ability to follow the cows and breed them, and it can impact sperm production as well,” he said.

Larson recommended that producers schedule a specific time every two to three days to check out how well the bull is moving. “Pencil it on your calendar to get out and check how he’s walking. Make sure he’s healthy in that way,” he said.

Good body condition during the breeding season is important. “Body condition for a bull tends to change slowly and the only reason it would likely drop is if he’s really in trouble, but it’s something to watch,” Larson noted.

Weaber said taking the ratio of bull-to-cow numbers into consideration can help maintain body condition for a young bull. As a rule of thumb for a young bull, Weaber recommends allowing the bull to service one cow per month of age at turnout.

“So, if he’s 15 months old, for instance, when you turn him out he can cover 15 cows for a 45- to 90-day breeding season,” Weaber explained.

For cattlemen with a two-season calving strategy, the team encouraged allowing extra recovery time for a young bull between breeding seasons.

“Make sure he gets plenty of recuperation time. And because he’s still trying to grow, put some extra feed into him so he’s in good shape at turnout for fall covers,” Larson said.

The complete podcast discussion is available to watch here .

Producers and veterinarians can submit a question to the Beef Cattle Institute at bci@ksu.edu.

50% of Bulls Fail BSEs due to Poor Sperm Morphology

What’s A Good Bull Worth?

Bull Management After the Breeding Season

Schedule Breeding Soundness Exams Before Turnout

Wed, 03 May 2023 16:46:56 GMT

This spring season has seen average temperatures in North Dakota 10 to 20 degrees colder than normal. Cold temperatures and wind can result in damage to bulls’ ability to produce viable semen. Bull breeding soundness exams offer the opportunity to identify and remove bulls from the breeding herd that have a low probability of siring calves.

“Since the number one determinant of profit potential in a beef cow-calf operation is birth of a live calf, turning out infertile bulls can have tremendous impact on profitability,” says Karl Hoppe, North Dakota State University Extension beef cattle specialist. “Breeding soundness exams can uncover potential problems with young bulls that were just purchased and older bulls that have already sired calf crops.”

However, less than 20% of producers in the United States perform breeding soundness exams on their bulls prior to spring turnout, according to a National Animal Health Monitoring Survey.

The breeding soundness exam performed by your veterinarian includes examination of the bulls’ physical structure, reproductive organs and semen.

“The physical examination is important because bulls with proper structure are more likely to hold up to the rigors of breeding season compared with bulls with structural problems,” says Dr. Gerald Stokka, NDSU Extension veterinarian and livestock stewardship specialist.

Structural problems with feet and legs or movement in general are a big issue because bulls are asked to cover a lot of ground and need to be free of physical problems to successfully breed cows. Young bulls will lose body condition during a breeding season, so they must enter the breeding season with adequate condition.

Vision is also an important part of the breeding season for bulls. Seeing the mounting behavior of cows in heat helps the bull identify who is ready to breed from across the pasture.

Evaluation of the reproductive organs is another important part of the breeding soundness examination. The penis, testicles, vesicular glands and other internal structures are evaluated. These organs need to be free of injuries, infections or defects in order for a bull to successfully breed cows.

Scrotal circumference is heavily scrutinized in young bulls as it serves as an indicator of semen production and fertility. As young bulls grow, the standards for adequate scrotal circumference also increase. For example, a bull that is less than 15 months old should have a circumference of at least 30 centimeters, whereas a bull greater than 24 months should have a scrotal circumference of at least 34 centimeters. Bulls with inadequate scrotal circumference should be discriminated against, as fertility and number of cows bred are a main concern. Extreme circumference size, for example greater than 40 to 45 centimeters in yearling bulls, has been linked with high failure rates of the breeding soundness exam.

A sample of semen is evaluated for motility, morphology and concentration. Motility is the movement of sperm. Ideally, a rapid swirling movement in the sample will be observed. If sperm are not moving in a synchronized manner, they may not be able to successfully navigate through the female reproductive tract to the site of fertilization. If a bull has less than 30% of sperm with proper motility, they are not recommended for breeding, whereas a bull with greater than 70% proper motility receives a very good rating for the motility portion of the exam.

Morphology is an evaluation of the structure of the sperm. Ideally, the sperm will have head and tails of proper shape. Examples of common defects include tapered heads, detached heads, folded tails and coiled tails. Sperm that have the incorrect structure will not result in successful fertilization, and a minimum of 70% of the sperm cells need correct morphology for a bull to pass a breeding soundness exam.

“Just because a bull sired calves last year does not mean he can do it again this year,” says Lisa Pederson, NDSU Extension livestock specialist. “Injuries during the non-breeding months as well as effects of extreme cold weather and frostbite can render once-fertile bulls infertile.”

The process of making sperm, spermatogenesis, takes 60 days, so frostbite or other injuries that occur in March may still be lingering in May. Perform breeding soundness exams close to the time of breeding to ensure recovery from winter injuries and enough time in advance of turnout to find new bulls if the exam finds fertility problems.

An important indicator of breeding season success is stocking rate, or how many cows a bull is required to breed in a breeding season. The nationwide average stocking rate is 25 cows per mature bull or 15 cows per yearling bull. Stocking rates of up to 50 cows per bull are used in some systems, but high stocking rates may lead to cows not becoming pregnant on their first heat of the breeding season and subsequently calving late the following year.

The breeding soundness exam does not, however, evaluate libido or willingness to breed.

“This is very important to keep in mind, especially when using young or virgin bulls,” says Hoppe. “Young bulls may have all of the qualifications to pass the breeding soundness exam, but if they aren’t actively breeding cows, producers must find a different option. Watch breeding activity closely because catching and correcting problems during the breeding season is much more profitable than waiting for open cows to calve.”

50% of Bulls Fail BSEs due to Poor Sperm Morphology

Mon, 16 May 2022 17:24:04 GMT

Data show that one of every five bulls tested fails a breeding soundness exam, according to the Society of Theriogenology, an organization dedicated to animal reproduction. A variety of reasons for that exists, says Jennifer Koziol.

“Multiple studies have shown us that about 50% of the bulls that fail breeding soundness exams do so because of poor sperm morphology,” says Koziol, DVM, MS, DACT, clinical assistant professor, Purdue College of Veterinary Medicine.

For a bull to pass a BSE as a “satisfactory potential breeder,” the Society maintains that 70% morphologically normal sperm – along with 30% progressively motile cells -- is the minimum standard.

But evaluating sperm morphology is not always a simple process. “The assessment is tedious and takes time,” notes Ahmed Tibary, DVM, MS, DSc, PhD, DACT, Washington State University professor and president-elect of the Society.

Some abnormalities of semen are difficult to see with the common staining techniques practitioners use. “Slide preparation is important; when in doubt fix semen samples in phosphate-buffered saline,” he recommends. “It’s also important to have a system to keep the slides and semen warm for evaluation of motility.”

Koziol says veterinarians need to look at sperm morphology at a high power with oil, with either brightfield or phase microscopy. “Looking at morphology slides at anything less than 1000X under oil or just looking at sperm motility and calling a bull satisfactory isn’t good enough,” she says.

Glen Jensen encourages practitioners to consider using a complete differential spermiogram (CDS) in their assessment of sperm morphology. A CDS breaks down and lists each of about 24 morphological abnormalities recognized by the Society, providing a more complete picture of the bull’s sperm production and quality.

“A significant benefit comes when we utilize the potential influences each type of morphological abnormality can have on fertility,” says Jensen, DVM, Emery Animal Health & Integris Cattle, Castle Dale, Utah.

Examples of this include detached heads and distal midpiece reflexes, which he says have very little negative effect on fertility until they reach levels of between 30% and 40 % in the ejaculate. On the other hand, he says proximal cytoplasmic droplets, nuclear vacuoles, and pyriform heads will begin to negatively impact fertility at around 15% to 20% of the ejaculate.

“Without a CDS this information is missing, and some subfertile bulls will be used while other bulls will receive an unsatisfactory classification yet would perform well,” Jensen says. “Using a CDS, veterinarians can better help producers make informed breeding management decisions through selecting the correct bulls for optimal herd reproductive performance.

Tibary routinely addresses common bull sperm abnormalities with his students at the Washington State University Veterinary Teaching Hospital.

“Describing the proportion of individual abnormalities is often not done in regular breeding soundness evaluations. However, in cases where the bull has a great value or there are many bulls failing because of the same abnormalities, this becomes very important in determining the possible causes and prognosis,” he adds.

Here are nine of the common abnormalities Tibary says to be on the lookout for:

Below are cropped copies of the nine photos above to, hopefully, give you a better perspective on the common sperm problems Dr. Tibary identified and highlighted in photographs:

1. Coiled principal piece

2. Detached heads are the black arrows/purple sperm. White arrows point to normal sperm.

3. Severely coiled midpiece

4. Proximal cytoplasmic droplet

5. Distal midpiece reflexes

6. Abnormal Head

7. Double Tail

8. Pyriform Head

9. Tapered/pyriform head with abnormal midpiece

When is the right time to castrate bulls?

Tue, 15 Mar 2022 18:43:42 GMT

The practice of castrating animals goes back to ancient times. Egyptian farmers found castrating bovine bulls made the animal much easier to handle. It’s doubtful the Egyptians were concerned about the value-added components of their animals. But today, adding value to market cattle is the name of the game and castration is a key component to any preconditioning program that can greatly influence market price premiums or discounts, especially in older bull calves.

Castrating bull calves has become common practice in U.S. beef herds. In 2017, the USDA-APHIS NAHMS Beef Cow Calf study indicated that 62% of commercial cow-calf herds used castration methods in their management practices. Castration has provided economic benefits to both the cow-calf producer and feedlot operators through increased market prices and meat quality. Castration also decreases unwanted pregnancy and increases the safety of workers and other animals.

There is a perceived notion that intact bulls have an advantage in body weight gains during the preweaning period and post greater weaning weights than calves castrated at or near birth. However, numerous studies have shown the weaning weights are similar for bulls and steers (approx. 600 lbs.). Advantages in calf weight gain due to testosterone production are presumably realized at a time following average weaning dates closer to puberty.

The timing of castration can influence weight gain and stress management. Studies examining how timing of castration effects average daily gains (ADG) in cattle castrated either in early life (birth to 2 mo.) or those castrated at weaning or postweaning (6-10 mo.) demonstrated higher ADG during the post-weaning period in the early castrated calves (approx. 0.30 lbs/day greater) than those castrated at or after. The period calves experience weight loss post-castration increases with age as does risk of disease susceptibility. The stress experienced is also related to the time of castration as the level of discomfort and trauma increases with the size of testicles. Calves castrated at 5 ½ months of age or later experienced a greater duration of stress than those castrated at birth or at branding.

Bull calves entering the stocker or feedlot segments of the industry have numerous health and performance factors associated with late life castration such as increased risk or morbidity and mortality, sick treatments and decreased ADG. Therefore, price discounts for bull calves being sold at market can be substantial when compared to steers marketed in the same weight class. Lighter weight bulls (300-400 lbs.) are viewed as less risky, and discounts are generally minimal if any. As the weight of a bull increases, so does the risk. Discounts can average $6-12/cwt or $30-60 per head.

A herd management practice that dates to ancient times and still used today has clearly proven beneficial. Utilizing the practice and with a timing that makes sense may be the difference between dollars made or dollars lost.

Castration is an important part of adding value to your calves through preconditioning. For more details and to enroll in the OQBN program go to www.oqbn.okstate.edu

Cows, Calves, and Cold Weather Concerns: Prepare for Winter Conditions

Tue, 25 Jan 2022 01:35:01 GMT

A high percentage of the U.S. beef herd resides in areas of the country where moderately to extremely cold winter temperatures are common. By planning for winter weather, ranchers can avoid being caught off-guard by extreme events and can manage the typical winter conditions so that cattle do not have to continually utilize body fat as an energy source to keep warm – leading to excessive loss of body condition.

Situations that are most likely to cause cold stress are: cattle with thin fat cover and short hair coats (due to movement from a warmer environment to a colder environment; or extremely cold temperatures early in the fall/winter season), cattle with wet hides, or high wind speed accompanying cold temperatures. Wind chill is a better predictor of cold stress than temperature alone because cold wind draws heat away more quickly than still air at the same temperature. Wet or mud-caked hair losses its ability to insulate the animal and a wet winter hair coat only provides as much protection from the cold as a typical summer hair coat. If cold wind is combined with a wet hair coat (as can occur during a winter storm), the effects can be very profound.

Adult cattle with a dry hair coat, adequate body condition, and abundant, adequate-quality forage can withstand most winter situations, especially if they have the ability to find protection from wind and have been exposed to moderately cold condition for several weeks which allows them to acclimate by growing a thick winter hair coat and increasing feed intake. As temperatures drop, cattle increase heat production which means that the number of calories they need for maintenance increases. This increase is met by consuming more feed and moving it through the digestive tract faster, but the cost of this faster movement is that feed is not digested as fully. The effect of needing increased calories for maintenance at the same time that feed digestibility is decreasing means that if cows do not have access to plenty of digestible feed, they will have to “burn” body fat as a calorie source. Another factor that can limit feed intake in winter conditions is if water sources are frozen or unavailable. If feed intake cannot keep up with energy demands, and body fat is mobilized to meet energy demands, then the cows will have less fat insulation and will be more susceptible to cold temperatures – causing a viscous cycle that can lead to cold stress and even more weight loss.

Cold weather brings a special concern with bulls because of the potential to have frostbite damage to the scrotum and testicles. It is very important that bulls have protection from the wind and adequate bedding if they are housed on concrete or dirt.

Cold temperatures have the greatest potential to cause serious problems in young calves, particularly calves in the first day of life. Because calves are born wet, have thin skin and very little body fat, they lose body heat very rapidly and if they are not able to become dry, can quickly become severely cold stressed. Contact with snow or wet ground will increase the amount of time that a calf stays wet and in danger. Body temperature of newborn calves can drop to dangerously low levels in 3 hours or less.

Calves are born with a body temperature of about 100˚F. When exposed to a cold environment, calves are able to produce heat in two ways, shivering and the heat production of brown fat (fat that surrounds the kidneys of a new-born) and they can conserve heat by reducing blood flow to the body surface and extremities (feet, ears, etc.). In early stages of cold exposure, calves will shiver vigorously and have a fast heart rate and breathing rate. If that does not keep the body temperature up, the calf’s body sends less blood to feet, ears, and nose in an effort to minimize heat loss. Severe cold stress occurs when the body temperature drops below 94˚F. At this temperature, the brain and other organs are affected and the calf becomes depressed, unable to rise, unwilling to suckle, and will temporarily lose the ability to shiver. The good news is that if the calf can be warmed-up and its body temperature can begin to rise, the shivering response will return and the core body temperature will slowly increase.

During periods of cold or wet weather, newborn calves (less than 1 to 2 days of age) should be checked every few hours with a thermometer and any calf with a below-normal temperature, even if it appears OK, should be warmed. Calves suffering from cold stress must be warmed so that body temperature can rise above 100˚F. If body temperature has not dropped too far, putting the calf in the cab of a pickup out of the wind and rain or snow will warm the calf. In more severe cases the calves can be placed in warm water, specially designed warming boxes, or near a heat source such as an electric blanket, heat lamp, or hot water bottles. To avoid skin burns, the heat source should not exceed 108˚F. In addition to an external heat source, cold-stressed calves should be fed warm colostrum, milk, or electrolyte fluid with an energy source using an esophageal feeder.

Prevention of cold stress involves management to ensure that calves can be born in a short period of time and both the calf and dam can stand shortly after calving so that they can bond and the calf can begin suckling. Anything that prolongs calving or reduces the chance that a calf will suckle soon after birth should be addressed by management changes. Calving difficulties are minimized by proper heifer development, proper bull selection for calving ease, and proper nutrition so that heifers and cows calve in a body condition score of 5 to 6 on a 9-point scale. Cows with large teats or that are not attentive mothers should be culled.

Use of pasture as the primary forage source during calving encourages cows to keep spread apart and minimizes development of muddy areas. If the herd forage plan includes feeding hay, consider feeding hay in early to mid-gestation and saving stockpiled pasture for the calving season. If supplemental hay and grain are fed during calving, these should be provided at locations that are separate and distant from water sources and windbreaks. I discourage the use of bale rings in calving and nursery pastures and suggest that if using large round bales, they be unrolled and the feeding area changed with each feeding. Unrolled bales will have greater hay waste, but reduced chance for mud caused by concentrating the herd into small feeding areas, and unrolled hay provides bedding for newborn calves so that they are not in direct contact with the ground.

In addition to monitoring the weather forecast for severe winter weather events and to be alerted to times when additional feed is needed, minimizing the effects of cold temperatures on newborn calves involves planning ahead and considering calf comfort and protection when making heifer development, bull selection, nutrition, and pasture management decisions. Making sure that cows will have adequate access to forage and water even in situations with significant snow cover is necessary to provide sufficient calories to maintain body fat and heat production. And, protecting the cowherd (and bulls) from winter wind and providing bedding if on concrete or mud/dirt will minimize the effects of severe weather.

The Bull Lameness Exam

Thu, 28 Oct 2021 20:28:17 GMT

The bull lameness exam Lameness can mean the difference between a valuable bull and hamburger. Identifying lameness and correctly diagnosing the cause of bull lameness can result in treatment success and potentially the retention of a valuable animal.

Meredyth Jones, DVM, MS, Dipl. ACVIM, Kansas State University, says 90% of lameness cases can be isolated to the foot, with 90% of claw lesions in the hind feet, mostly in the lateral claw. The causes of lameness in bulls are many (see sidebar), so it’s important to take a targeted approach to diagnosis.

Footrot is the most common cause of lameness in cattle, but most of those cases are managed on-farm. “The most common things I see on farms as primary care cases are toe abscesses and subsolar abscesses,” Jones says. “I also see a fair number of subcutaneous abscesses that occur over the shoulder or thigh, usually as the result of fighting. Beyond those, spinal trauma, developmental orthopedic diseases such as osteochondritis dissecans and spastic paresis occur with enough regularity that I keep an eye out for them.”
Spastic paresis, spastic syndrome, and corkscrew claw all likely have a heritable component. “We certainly see spastic paresis associated in cattle with overly straight hocks,” she says. “The developmental orthopedic diseases, like osteochondritis dissecans, are multifactorial with genetics, nutrition and environment likely all contributing. The real take home message is that, when making breeding and culling decisions, musculoskeletal and hoof quality should be important considerations.”

Jones offers these recommendations for conducting a lameness exam on a bull.

1. START WITH HISTORY
Jones starts every lameness exam with as complete of a history on the bull as she can get. “Duration of the lameness and any previous history of lameness or systemic illness prior to this episode are useful to know when evaluating the animal,” Jones says. “Of particular interest to me when I’m evaluating a case is the progression of this episode of lameness, treatments that have been done on the farm and any response to those treatments.”
Jones says one of the most common things she sees is that the bull becomes lame, he gets treated with antimicrobials, usually oxytetracycline because it’s presumed to be footrot, and then he doesn’t respond. “At this point, the bull needs to be examined because a simple case of footrot will almost always respond to a single dose of oxytetracycline,” she explains. “When that is the history, the veterinarian knows to go on a more aggressive hunt for the cause of the bull’s lameness.”

2. WHAT’S HIS JOB?
Depending on how the bull is used can influence treatment choice or disposition. The primary career choices for bulls are to be range or pasture bulls, AI sires or a combination. “We generally don’t see bulls in the feedlot, or prefer not to, but this may be a career option for young bulls that perhaps were intended to be sires, but were channeled into the feeder route because of another reason,” Jones says. “Certainly, producers are generally more willing to go for more aggressive therapy with higher economic value bulls. I believe and teach my students that every case you see has three options for management: low-cost, middle-of-the-road and the Cadillac. Each of those has a cost estimate, aftercare and prognosis associated with it and veterinarians are there to educate their clients so they can make informed decisions.”

From another perspective, what the bull is expected to do for a living plays heavily in his prognosis for certain diagnoses. “For example, if the bull has distal interphalangeal septic arthritis in the lateral claw of the hind limb, we may be able to surgically manage him to be an AI sire or for small pasture breeding, but he may have reduced longevity in a large rangeland situation,” Jones says. “We want to be able to be very up front with producers about the prognosis for return to soundness for each type of breeding situation so that they can decide in their own mind if that is acceptable to them.”

3. LOOK AT THE WHOLE PACKAGE
Jones says when she looks at a bull for any reason, his body condition is always something on her mind. “If a young bull presents for lameness and he is very obese, it may be a clue as to his nutritional management (very high energy feeds and overfeeding) and would move developmental orthopedic disease up on my list,” she says.
Jones adds how he got to the body condition he’s in may be a bigger factor in his disease and recovery than his actual condition at the time of evaluation. “Has he been out covering a lot of cows over a lot of ground? Is he still a young, growing bull that is breeding cows and is not being fed to meet both of those demands and he’s just getting run down in general? If he’s overfat, is that extra weight contributing to the strain on his joints or will it make his recovery more difficult? In many cases, body condition may not have a direct impact on lameness, but it certainly adds to the bull’s entire story which must be considered when managing him.”

4. THE “DISTANCE EXAM”
Certainly, the mantra of most veterinarians is that they want the animal caught up when they arrive on the farm, and Jones holds to that as well, but with a slight difference. “For lameness cases, my definition of ‘caught up’ is in a small trap or pen where there is room to walk him around. I don’t need 400 acres to see him walk, but likewise, I cannot evaluate his gait or see his whole body in the alleyway or chute either.”
Jones explains that when she can see the whole bull and walk him, she can look for subtle swellings, figure out exactly which leg is the problem or see if it is her impression that the problem might be up in his spine. “His degree of lameness also gives me a lot of information about the cause of his lameness. If I see a swelling in the area of a joint and the bull won’t put the leg down, then I have a pretty good feeling that the joint is septic, rather than just having a sprain or effusion.”

Jones says while she don’t see them with great regularity, diseases like spastic paresis and spastic syndrome are actually best diagnosed while observing the gait and once they are in the chute, there’s not really much to do with them except rule out other disease processes.

Jones adds that she can also evaluate his symmetry and detect any muscle atrophy by watching him walk. Disuse atrophy generally becomes noticeable after about two weeks of disuse, which helps the veterinarian get a sense of the duration of the lameness.

In cases where animals that are severely lame or have evidence of neurologic disease, Jones has to really consider the wisdom of even putting the animal in the chute and risking not being able to get them out. “In those cases, I’m going to consider casting restraint or sedation in a pen if further evaluation is necessary.”

5. RESTRAINT AND PALPATION
After Jones has seen the bull walk and feels comfortable sending him to the chute, she prefers to palpate the entire limb, particularly when it is a hind limb, prior to using a rope to pick up the foot. “We know that greater than 90% of lameness lesions are in the foot, so it’s logical to go there first, but if this guy has a partially ruptured cruciate ligament and I put a rope on his foot and pick it up and he struggles for a minute, which they always do, then I may have just finished off his cruciate.” The same could be true for fractures or other unstable upper limb lesions.
Many cases have obvious swelling and when that’s the case, Jones palpates for any heat or coolness of the area and determining the character of that swelling: is it soft and fluctuant, firm or hard like bony proliferation? As the swelling increases in firmness, the chronicity of the process is usually increased and will likely result in the need for more aggressive therapy.

From the elbow and stifle up, palpation is more challenging. “I will often go back and forth from one elbow or shoulder to the other comparing the size and character of the joint to convince myself that the joint on the lame leg is normal or abnormal,” Jones suggests. “In the case of the stifles, I am generally able, even on large bulls, to place my hands on both stifles from behind the bull at the same time, making the comparison of size more direct.”

Evaluation of the hip requires palpation of the position of the greater trochanter of the femur relative to the ileal wing and ischiatic tuberosity. The three should form a triangle with the greater trochanter at the low point and if the greater trochanter is displaced , this indicates a hip dislocation. Further evaluation of the hip and pelvis really requires rectal palpation and casting restraint or sedation to put the limb through range of motion to palpate for crepitus.

6. HAVE THE RIGHT TOOLS
Jones carries in the truck a foot box that contains a hoof tester, hoof nippers, half-round hoof nippers, Swiss knife, regular hoof knife, stainless steel teat cannulas, lidocaine, innertube tourniquet and butterfly catheters for foot anesthesia, and supplies to place a wooden block. “The most common hoof issues that I see are toe abscesses and subsolar abscesses. They can be discovered by trimming with foot trimmers or paring away the sole with hoof knives. Once discovered, these need to be opened completely, wide enough to provide good drainage. This is not for the faint at heart and, if I’m going to get down to sensitive tissue, I will place a tourniquet at the mid-cannon bone and perform a Bier block (regional intravenous perfusion of lidocaine) to anesthetize the foot to allow me to be aggressive. As I’m working, I use a teat cannula to probe to find every bit of undermined tissue and get it removed.”

Jones advises to not quit too soon. “Sometimes, I’ve had cases where I removed the entire sole. If it is undermined, it has to go. I have found halfround hoof nippers to be the best tool for peeling off the dead, infected sole.”

Jones finds that ultrasound is useful in evaluating the fluid character of effusive or enlarged joints, and for diagnosing septic tenosynovitis, as a backup to her clinical impression. “People who are really experienced with ultrasound can find cartilage flaps, bursitis and even fractures with ultrasound,” she says. If arthrocentesis is to be performed for cytology, protein concentration and culture of the joint fluid, ultrasound guidance is useful.
Radiographs are also useful in some lameness cases and portable units can provide some good images of lower limb conditions. “All that said, I really believe that the vast majority of cases can be accurately diagnosed, prognosed and treated after a thorough clinical exam.”

For more on bull health and bull examinations, read these articles on BovinVetOnline:

BSEs for Young and Mature Bulls

Don’t Forget the Bulls

Build Business with BSEs

Sidebar

How bull lameness happens

Bulls are aggressive and frequently groups of bulls are put together, often ranging in age. Young bulls, when placed with an established group of bulls, should be monitored closely to ensure that they don’t become the whipping boys which usually manifest as shoulder injuries, explains Meredyth Jones, DVM, MS, Dipl. ACVIM. “Whenever possible, bulls should be allowed to spread out. Confinement, even for a short time, often results in a fight.”

A bull’s hind legs and back are under a tremendous amount of strain during breeding. “Acute injuries, from mild sprains to ligament tears can occur, but the chronic wear-and-tear is what prematurely ends the careers of most bulls,” Jones says. “Spinal and limb pain may be severe enough to reduce semen quality to an unacceptable level or can result in a bull limiting or even totally ceasing to mount cows.”

Bulls often have to travel long distances such as in range pastures, and footing is a contributor to lameness. “Two environmental conditions that most significantly affect a bull’s feet are very dry and very wet,” Jones says. “Very dry ground predisposes hooves to cracking vertically, which can get deep enough to pinch the sensitive laminae with every step. Very wet ground is a big risk factor for footrot, but can also result in softening of the soles, making them more vulnerable to bruising.”

Causes of lameness
Jones offers this list of common causes of lameness, categorized by which part of the foot or leg they are usually found. “My goal with this is to give veterinarians a starting point of ideas to entertain when they localize a lameness to a particular anatomic location,” Jones explains.

“In general, this can be done fairly easily during the clinical evaluation, but every once in a while, they can be tricky. In lameness evaluation of horses, local anesthesia as a means of lesion localization has become mainstay. We do it some in cattle, but it certainly isn’t common. The disease processes which cause lameness in cattle tend to be infectious or inflammatory, making them fairly easy to spot in most cases.”

Foot: Mechanical causes
• Sole ulcer/sole abscess/toe abscess
• Corkscrew claw
• White line disease/laminitis
• P3 fracture>P2>P1
• Interdigital fibroma (corn)
• Vertical wall crack
• Horizontal crack

Foot: Infectious/septic causes
• Septic arthritis of DIP joint>MTP>PIP
• Septic tenosynovitis
• Pedal osteitis
• Papillomatous digital dermatitits

Metatarsus/Metacarpus
• Physitis
• Fracture
• Cellulitis

Carpus
• Hygroma
• Septic arthritis

Elbow
• Septic arthritis

Humerus
• Hematoma
• Fracture

Shoulder
• Hematoma
• Septic arthritis
• OCD

Hock
• Conformation issues
• Septic arthritis
• OCD

Tibia
• Fracture
• Cellulitis

Stifle
• Septic arthritis
• Cranial cruciate rupture
• OCD

Femur
• Diaphyseal fracture
• Distalphyseal fracture

Hip
• Slipped capital physis
• Coxofemoral luxation

Spine
• Trauma
• Fracture/luxation
• Spastic syndrome
• Ankylosing spondylitis
• Spinal lymphoma
• Epidural abscess
• Vertebral body abscess