9 min read Last updated: January 2026 Choosing between hay and haylage can feel like a trade-off between clear airways, calorie control and storage ease. Here you'll learn when haylage is the safer, low-dust option, exactly how much to feed (about 1.5 times the weight of hay), and how to use opened bales within 27 days for healthier lungs and steadier routines. Quick Summary Short on time? Here are the key takeaways. Area: Forage Choice What To Do: Choose quality haylage for most dust-sensitive UK horses; pick later-cut, drier haylage or steamed hay for good-doers. If you need outdoor storage, consider wrapped hay but weigh up dust needs. Why It Matters: Haylages moisture reduces respirable dust while the right cut controls calories. Common Mistake: Treating wrapped hay as true haylage and expecting the same dust reduction. Area: Portion by Dry Matter What To Do: Feed about 2% of bodyweight as dry matter; when moving from hay (~85% DM) to haylage (5070% DM), increase to roughly 1.5 the hay weight and weigh nets. Why It Matters: Hitting DM targets keeps fibre adequate and weight stable. Common Mistake: Feeding haylage at the same weight as hay, leaving fibre short. Area: Safe Switch Plan What To Do: Transition over 7 days (75/25, 50/50, 25/75, 100%) with fixed timings and from the same bale. Monitor droppings and appetite; slow the change if anything shifts. Why It Matters: Gradual changes protect the hindgut and cut colic risk. Common Mistake: Switching overnight or mixing multiple batches during the change. Area: Respiratory Management What To Do: Use haylage for coughy or allergic horses; if needed, steam forage and improve stable ventilation to cut dust. Handle nets and muck out when the horse is out. Why It Matters: Reduced airborne particles support clear airways and performance. Common Mistake: Soaking haylage (its unnecessary) or persisting with dusty hay. Area: Haylage Storage & Shelf-life What To Do: Store wrapped bales on well-drained ground, guard the plastic, and reseal tightly once opened. Use within 27 days in summer or up to ~3 weeks in winter for drier types, checking smell and look before each feed. Why It Matters: Limiting air and heat prevents mould and spoilage. Common Mistake: Opening a bale larger than your yard can finish safely in time. Area: Bale Quality Check What To Do: Inspect colour (golden/green), smell (clean, sweet), texture (slightly moist, pliable), and weed content; check wrap for punctures. Reject musty, sour, metallic or weedy bales. Why It Matters: Quick checks stop unsafe forage reaching the manger. Common Mistake: Feeding from bales with minor punctures or a faint musty note. Area: Forage Analysis & Calories What To Do: Send forage for analysis (DM, sugars, energy, protein) and adjust type/portions with vet or nutritionist advice, especially for good-doers, laminitics, elderly or performance horses. Re-test with each new batch. Why It Matters: Data-led feeding prevents weight creep and performance dips. Common Mistake: Assuming all haylage is the same and guessing portions. Area: Bale Size & Logistics What To Do: Match bale size to how fast youll use it; single-horse owners should buy smaller bales. Use slow-feed haylage nets to pace intake and reduce waste. Why It Matters: Right sizing keeps forage fresh, cuts costs and supports steady eating. Common Mistake: Buying big bales in warm weather and exceeding safe post-opening times. In This Guide Hay vs haylage: the core difference How much should you feed? Is haylage better for respiratory health? How to switch safely from hay to haylage Storage and shelf-life: how long does haylage last? UK weather: when and why haylage shines Haylage quality checklist: what to look for Choosing between hay and haylage affects your horses lungs, waistline and your yard routine. With UK weather and storage to consider, the right choice is about more than preference its about health, practicality and consistency.Key takeaway: For most UK horses needing dust-free forage, quality haylage is the safer daily choice but you must feed about 1.5 times more by weight than hay and use opened bales within a week.Hay vs haylage: the core differenceHay is typically 8590% dry matter (DM), while haylage sits around 5070% DM, so you need roughly 1.5 times more haylage by weight to deliver the same fibre intake. Haylages higher moisture also traps dust and spores, making it lower risk for respiratory issues than hay.Both are grass forages, but theyre made differently. Hay is field-dried until most moisture is gone, then baled and stored indoors. Haylage is cut earlier, wilted for a shorter period (around three days in the UK), then baled and sealed to ferment slightly. That moisture is the big functional difference: more water, less dust, and a pickier shelf-life once you open the wrap.Dry haylage or wrapped hay sits between the two, with more moisture than hay but not enough for proper fermentation. It can be handy for outdoor storage, but it wont reduce dust as effectively as true haylage and generally retains higher sugars.The biggest benefit of haylage over hay for many owners is that haylage is dust free. The moisture in haylage can absorb any potentially harmful spores that horses can inhale, and they stick to the grass meaning theyre eaten instead of breathed in. Baillie HaylageHow much should you feed?A 500 kg horse needs about 10 kg of dry matter daily: thats roughly 11.7 kg of 85% DM hay or 14.2 kg of 70% DM haylage. As a rule of thumb, feed about 1.5 times more haylage by weight than hay when DM differs.Dry matter (DM) is the fibre and nutrients left after you remove the water. Because haylage carries more water, you must feed a heavier amount to hit the same DM target. For most leisure horses, aiming for 2% of bodyweight in DM per day (so ~10 kg DM for a 500 kg horse) works well.Example with hay (85% DM): 10 kg 0.85 = 11.7 kg fresh weight per dayExample with haylage (70% DM): 10 kg 0.70 = 14.2 kg fresh weight per dayFor precision, get your forage analysed for DM, energy and protein. Thats especially important if your horse is in hard work, elderly, overweight, or laminitic. Higher energy haylage can tip good-doers over their calorie needs; in these cases, consider drier, later-cut haylage, restrict portions, or use steamed hay alongside a low-calorie balancer as advised by your vet or nutritionist.Pro tip: Weigh what you feed. Pop a small luggage scale on your haynet ring and note down what a full net actually weighs in your yard, for both hay and haylage.Is haylage better for respiratory health?Yes haylages moisture helps absorb dust and mould spores, making it effectively dust-free and safer for horses with allergies or compromised airways than hay. If you still need extra hygiene, steam either forage to reduce respirable particles further.Respiratory comfort is the biggest everyday win with haylage. Fewer airborne particles mean fewer triggers for coughs, nasal discharge and performance-limiting inflammation. This benefit is particularly relevant in busy UK yards where indoor storage and mucking out can add to dust loads.Haylage features a dust-free composition, reducing the risk of respiratory issues compared to traditional hay. Its moisture content helps absorb dust and mould spores, making it a safer choice for horses with allergies or compromised respiratory systems. Millbry HillIf your horse requires dust-free forage but needs the extra nutrients and energy that would be lost through soaking, haylage is an ideal solution. Once opened, it needs to be used quickly depending on conditions, this can be anywhere from 27 days. Horse & Rider UKAt Just Horse Riders, we often recommend pairing haylage with targeted support if your horse is particularly sensitive. Explore respiratory supplements for clear airways and trusted brands like NAF respiratory support to complement good forage choices. After riding or mucking out, a thorough brush-down helps too stock up on yard-favourite tools in our grooming collection.How to switch safely from hay to haylageTransition over about 7 days, gradually increasing haylage while reducing hay to avoid digestive upset or colic. Any abrupt forage change can disturb hindgut microbes, so slow and steady is essential.Follow a simple plan:Days 12: 75% hay, 25% haylageDays 34: 50% hay, 50% haylageDays 56: 25% hay, 75% haylageDay 7: 100% haylage (adjust final intake to hit your DM target)Maintain routine feeding times, introduce from the same bale for consistency, and monitor droppings and appetite. If your horse is sharp on richer forage, choose a drier, later-cut haylage and balance overall calories accordingly. For horses prone to ulcers or stress, multiple small haylage nets can keep fibre trickling through the gut and behaviour on an even keel.Quick tip: Single-horse owners should opt for smaller haylage bales to minimise waste once opened especially in warmer months when shelf-life shortens.Storage and shelf-life: how long does haylage last?Unopened, wrapped haylage stores well outside; once opened, use within 27 days in summer, or up to 3 weeks in winter for drier types (around 80% DM). Exposure to air invites mould, so plan bale size to match your yards usage rate.Store unopened bales on well-drained ground, protect the wrap from punctures and keep birds/vermin away. Once opened, reseal tightly and use quickly particularly in warm, humid weather. Drier high DM haylages last better through UK winters, but always inspect before each feed. Good haylage smells fresh and sweet; musty, metallic or acrid notes mean its past its best.Hay, by contrast, needs dry, well-ventilated indoor storage on pallets to prevent ground moisture wicking and mould formation. Barn drying is less common in the UK, so field-dried hay can be more variable; check bales closely on delivery and throughout the winter.If your horse is stabled on hay or haylage through colder nights, ensure they stay comfortable with the right layering browse dependable stable rugs for winter stabling. For practical feeding, brands like Shires offer robust haylage nets and yard tools to keep things tidy and slow feeding sensibly.UK weather: when and why haylage shinesIn the UK, haylage suits unpredictable summers because it needs only about three days to wilt and is typically harvested from early June to September. That shorter drying window means more reliable forage production when consecutive dry days are scarce.UK rain patterns can turn haymaking into a gamble. Haylages faster process reduces the risk of showers washing away nutrients or encouraging dust and mould. Its also friendlier on storage: wrapped bales can sit outdoors, which suits livery yards short on barn space. If your horse lives out while youre feeding in the field, a reliable rug helps weather the drizzle our range of winter turnout rugs keeps horses drier and more comfortable during stop-and-feed routines. And if youre checking fields or moving bales in dull autumn light, stay seen with rider-safe hi-vis gear.Haylage quality checklist: what to look forGood haylage is slightly moist, sweet-smelling, leafy and golden with pliable stalks; reject bales that are faded yellow/brown, weedy, or smell musty, metallic or acrid. Always inspect before feeding.Use this quick checklist:Colour: Golden to fresh green, not dull or brownSmell: Clean and sweet; never sour, acrid or metallicTexture: Slightly moist, leafy, pliable stems (not brittle)Contents: Minimal weeds; consistent, even chopWrap: Intact with no punctures; use bales from the same batch for consistencyOpen bales carefully to avoid tearing the wrap if youll be resealing. If youre aiming for a longer post-opening window in winter, look for drier haylage (7080% DM), and monitor it daily. For horses that still react to any dust (e.g. when swapping back to hay part-time), steam the forage and keep noses clean with a quick flick over from your grooming kit.Pro tip: Forage analysis pays you back in confident feeding. Knowing DM, sugars and protein lets you fine-tune portions, especially for good-doers or performance horses.FAQsIs dry haylage just wrapped hay?Yes. Wrapped hay (sometimes marketed as dry haylage) has slightly higher moisture than standard hay but not enough to ferment like true haylage. It wont reduce dust as effectively and generally retains higher sugars, but its convenient for outdoor storage.Is haylage safe for horses with breathing problems?Yes. Haylages moisture traps dust and mould spores, so its typically safer for horses with allergies or compromised airways than hay. For extra hygiene, steam the forage, keep stables well-ventilated and consider targeted respiratory support via supplements from trusted brands like NAF.How much more haylage do I need to feed vs hay?About 1.5 times more by weight to supply the same fibre. For example, a 500 kg horse needs around 10 kg DM daily, which is roughly 11.7 kg of 85% DM hay or 14.2 kg of 70% DM haylage. Weigh your nets and, if possible, analyse your forage DM for accuracy.How long does opened haylage last?Use opened haylage within 27 days in summer. In winter, drier types at around 80% DM can last up to three weeks if kept sealed and cool. Always check smell and appearance before every feed.Can I store haylage outside in the UK?Yes. Wrapped bales are designed for outdoor storage on well-drained ground; protect the wrap from punctures and vermin. Hay, by contrast, needs dry, raised, and well-ventilated indoor storage.Should I pick haylage or wrapped hay?Choose haylage if you want dust-free forage and can use an open bale quickly. Pick wrapped hay if you need outdoor storage but dont require fermentation benefits. For overweight or laminitic horses, speak to your vet or nutritionist and consider lower-energy options or steamed hay.At Just Horse Riders, were here to help you match forage, management and kit to your horse and yard. If youre adjusting routines for winter, explore practical layers like stable rugs, field-ready turnout rugs, and yard essentials from Shires and breathe easier with smart respiratory support from NAF and our wider supplements range. Shop the Essentials Everything mentioned in this guide, ready to browse. Shop SupplementsShop NAF SupplementsShop ShiresShop Stable RugsShop Turnout Rugs

Two well-known British equestrian brands, Nuumed and Thermatex, have found a new home with Racesafe and will continue to be manufactured in the UK.Racesafe, which makes body protection and performance apparel, is integrating both brands into its existing production base. A statement said the move aims to provide the stable manufacturing structure and technical expertise needed to support long-term growth. Long established across multiple disciplines, both Nuumed and Thermatex have earned loyal followings and their products are fixtures in many tack rooms and shops. In recent years, however, like many UK manufacturers, the brands faced increasing commercial pressures.Nuumed and Thermatex are brands that mean a great deal to riders and retailers alike. They have strong foundations and loyal customers, and we believe they deserve a stable and properly resourced future, said James How, managing director of Racesafe.As a specialist UK manufacturer, we see real opportunity in combining their heritage products with Racesafes technical expertise, product development capability and manufacturing strength. Our intention is not simply to restart them, but to strengthen and evolve them carefully so they can thrive again.Product relaunchProduction will take place in the Racesafe factory, with an initial core range expected to return to the market in the coming months. The company is working closely with retailers to prioritise the most commercially important and much-loved products.Members of the former Nuumed and Thermatex teams are working alongside Racesafes machinists to transfer knowledge and support a careful and structured restart of the ranges.We are proud to keep these brands made in Britain, added James. Retaining skills, knowledge and local production capability is vital for the long-term health of our industry. With the right structure and investment, British manufacturing remains both viable and important.Further updates on product availability and relaunch timelines will be announced in due course.Related contentUpdate on Charles Owens UK operations as statement leaks on social mediaTherapy horse rugs tried and tested to find which really workBest exercise sheets as rated by our team of horse owners and riders14 versatile cooler and travel rugs for horsesThe post Racesafe secures Nuumed and Thermatex, keeping production in Britain appeared first on Your Horse.

A fresh look at where, how, and why injuries happen in todays various equine sportsSoft-tissue injuries, including tendinitis and desmitis (ligament inflammation) are some of the most common career-ending injuries seen in horses. | iStock photoFor some equine athletes a torn suspensory ligament or degenerating pair of hocks marks the premature end of a competitive career. The musculoskeletal injuries we commonly see in different types of horses arent entirely randomthey often reflect the unique physical demands of each discipline. Looking at the current research and speaking with veterinary specialists, heres what we know so far about the predisposition of horses to discipline-specific sports injuries.The No. 1 Reason for Premature Retirement in Sport HorsesKara Brown, VMD, assistant professor of equine sports medicine and rehabilitation at the University of Pennsylvanias New Bolton Center, in Kennett Square, starts by acknowledging musculoskeletal disease as the single most common cause of premature retirement in equine athletes. Osteoarthritis, tendinitis, and desmitis (ligament inflammation) top her list of the most common career-ending injuries. Thats problematic because the inherent poor healing characteristics of cartilage, tendon, and ligaments make these types of injuries difficult to treat and prone to reinjury, she explains. That being said, advances in the management of these disease processes are certainly giving us more opportunities to intervene prior to the need for retirement.How Discipline Affects Equine Injury RiskMuch like tennis players develop the aptly named tennis elbow and long-distance runners often suffer from plantar fasciitis, equine athletes most common injuries closely link to their discipline. Discipline often reflects breedfor example, Quarter Horses in Western events, Warmbloods in dressage and show jumping, and Thoroughbreds or Standardbreds in racing. As a result veterinarians often see specific injuries correlate with specific breeds, pedigrees, conformation, and other related factors beyond the discipline itself.There are certainly many injuries that are overrepresented in certain disciplines and populations of horses, says Kim MacKinnon, DVM, CVA (Eq), an associate veterinarian at Avon Animal Hospital, in Windsor, Nova Scotia, Canada, with primary clinical interests in equine lameness and sports medicine. Different biomechanical forces are at play on a reining horse performing a sliding stop, for example, than a show jumper jumping a 1.45-meter course, or in a three-day eventer competing in consecutive dressage, cross-country, and show jumping phases of the event. We are asking these horses to use their bodies differently based on the maneuver, exercise, or obstacle. There are sport-specific biomechanical patterns that we are able to appreciate, which correspond to repeated loading of specific structures according to discipline.In any discipline Brown cautions equestrians against overusing certain movements and neglecting variety in training. With respect to management and training practices across disciplines, we find that horses that perform repetitive activities without diversity or variability in movement appear to be at higher risk for musculoskeletal injury, she says.Cross-training the horse allows multiple joints and muscles to share cumulative orthopedic stress. | Adobe stockBrianne Henderson, BVMS, MRCVS, of Ferguson Equine Veterinary Services, in Ontario, Canada, says varying training modalitiessuch as hillwork, trail riding, or swimmingallow joints and muscle groups to share cumulative orthopedic stress, reducing focal overload on vulnerable areas including hocks or suspensory ligaments.That being said, to some extent, the types of movements and activities required for performance cannot be altered, and its very important that the horses musculoskeletal tissues are gradually prepared for the stresses they undergo during competition, and also that the athletes are cardiovascularly prepared from a fitness perspective, Brown explains.Performance Level, Fitness, and Age Matter, TooDiscipline tells part of the story, but the level and intensity of competition add another dimension to injury risk. There appears to be a further subdivision between discipline and level of performance in terms of what injuries we are seeing, MacKinnon says. Age also plays a role in the injury patterns we see, as repetitive injuries and degenerative (joint) disease catch up with the horse as they undergo more wear and tear on soft tissue and osseous structures as they age and continue to perform.Researchers on a retrospective analysis of more than 1,000 horses and ponies undergoing orthopedic evaluation found elite competitors in eventing, show jumping, and dressage were far more likely to suffer injuries to specific structures compared to nonelite or general-purpose horses.1 Fitness level matters as much as performance level, it appears. In a different study of elite Thoroughbred eventers, horses labeled as good performers based on VLA4 (velocity at 4 millimoles/liter of blood lactatean exercise physiology marker used to assess aerobic vs. anaerobic capacity) and recovery heart rate had zero injuries, while average performers sustained injuries 50% of the time (P=0.05).11 Additionally, horses that remained sound had significantly lower peak heart rates during conditioning (186 beats per minute) than horses that sustained injury (201 bpm).Most Effective DiagnosticsWith todays diagnostic imaging tools, veterinarians can detect and treat injuries in sport horses before they progress to performance-inhibiting lameness. We are fortunate to have a diverse array of advanced imaging modalities, which are becoming more readily available and accessible in addition to what ambulatory veterinarians have in their trucks on a daily basis, MacKinnon says. The portability and ease of use of digital radiograph (X ray) units and ultrasound machines have elevated our point-of-care diagnostics in the past 1520 years and are now the standard of care. Advanced imaging modalities, such as positron emission tomography (PET) scans, computed tomography (CT) scans, high- and low-field MRI, and nuclear scintigraphy (bone scan) are also now all routinely used to diagnose injuries, prognosticate injuries, and develop treatment/rehabilitation plans tailored to the patient and specific injury.She says she considers the use of PET scans in clinical practice an exciting diagnostic tool. We are continuing to learn more about it in terms of what it can tell us about bone and soft tissue injury, both by itself and in conjunction with other imaging modalities, such as MRI, CT, and nuclear scintigraphy. PET has shown exciting promise to provide functional information about the activity of an injury, elucidating injury prior to appreciating structural change, determining the stage of healing of injuries, and in early detection of injuries prior to other modalities in some cases.Most Effective TreatmentsThe past few decades have brought major advances not only in diagnostic approaches but also in options for treating injured equine athletes. Experts agree the single most influential advancement in the treatment of equine musculoskeletal injuries remains regenerative medicinenotably orthobiologics, which use the healing properties of the horses own cellular components (from blood or stem cells) without the adverse effects of corticosteroids.RELATED CONTENT: Equine Innovators Podcast: Improving Joint Health in Horses With OrthobiologicsBrown says regenerative therapies play a critical role in extending the athletic careers of sport horses, particularly in the case of managing osteoarthritis and soft tissue injuries such as tendinitis and desmitis. For many years management of osteoarthritis was restricted to symptom-modifying treatments like joint injections with corticosteroids and systemic anti-inflammatories. While these can be very effective, from the perspective of long-term management of a performance horse, there are some downsidesthe repeated use of corticosteroids in the joint can be damaging to the cartilage, she says.Additionally, in older horses, the combination of endocrine disease such as pituitary pars intermedia dysfunction (PPID, formerly known as equine Cushings disease) and corticosteroid administration can increase the risk of adverse events, including laminitis, Brown explains. As for systemic anti-inflammatories, their use is often regulated during competition, and long-term administration can have adverse effects on both the gastrointestinal system and kidneys.She suggests regenerative medicine as a viable alternative for delivering targeted anti-inflammatory therapy to the joint without the potential adverse effects associated with corticosteroid treatments. Not only that, but there is now good data supporting the use of regenerative medicine therapies like platelet-rich plasma (PRP), autologous protein solution (APS), and stem cells, to improve the quality of healing soft tissues and decrease reinjury rate, explains Brown. From the perspective of soft tissue injury, optimizing the quality of healing is essential for reducing reinjury, which is a very common problem for tendon and ligament injuries.Take-Home MessageAdvanced imaging and regenerative therapies give equine veterinarians unprecedented ability to detect, treat, and manage musculoskeletal injuries. Identifying injured horses early remains a top priority. By understanding how and why injuries happen in different horse sports and applying that knowledge to reduce their occurrence through strategic conditioning, cross-training, and early intervention, we can improve outcomes and extend the careers of our equine athletes.References1. Murray RC, Dyson SJ, Tranquille C, Adams V. Association of type of sport and performance level with anatomical site of orthopaedic injury diagnosis. Equine Vet J. 2010;38(S36):411416.2. Rogers CW, Bolwell CF, Gee EK. Proactive management of the equine athlete. Animals. 2012;2(4): 640655.3. Singer ER, Barnes J, Saxby F, Murray JK. Injuries in the event horse:training versus competition. Vet J. 2008;175(1):7681.4. Johnson SA, Donnell JR, Donnell AD, Frisbie DD. Retrospective analysis of lameness localisation in Western performance horses: A ten-year review. Equine Vet J. 2021;53(6):11501158.5. Holbrook TC, Schoonover MJ. Veterinary Aspects of Conditioning, Training, and Competing Western Performance Horses. Equine Sports Medicine and Surgery (Third Edition). 2024;12721287.6. Wilsher S, Allen JL, Wood N. Factors associated with failure of Thoroughbred horses to train and race. Equine Vet J. 2010;38(20):113118.7. Parkin T, Lam K, Riggs C, Morgan K. Risk factors for tendon injuries that result in retirement from racing at the Hong Kong Jockey Club. Management of Lameness Causes in Sport Horses. Leiden, The Netherlands: Wageningen Academic, 2006.8. Shrestha K, Gilkerson JR, Stevenson MA, Flash ML. Drivers of exit and outcomes for Thoroughbred racehorses participating in the 20172018 Australian racing season. PLOS ONE. 2021;16(9):e0257581.9. Sousa NR, de Luna SPL, Pizzigatti D, Martins MTA, Possebon FS, Aguiar ACS. Relation between type and location of orthopedic injuries and physical activity in horses. Cinc Rural. 2017;47(2).10. Wright I, Minshall G, Young N, Riggs C. Fractures in Thoroughbred racing and the potential for pre-race identification of horses at risk. Equine Vet J. 2024;56(3):424436.11. Munsters C, van den Broek J, Welling E, et al. A prospective study on a cohort of horses and ponies selected for participation in the European Eventing Championship: reasons for withdrawal and predictive value of fitness tests. BMC Vet Res. 2013;9:182.This article is from the Research Roundup 2025 issue ofThe Horse: Your Guide to Equine Health Care. We at The Horse work to provide you with the latest and most reliable news and information on equine health, care, management, and welfare through our magazine and TheHorse.com. Your subscription helps The Horse continue to offer this vital resource to horse owners of all breeds, disciplines, and experience levels. To access current issues included in your subscription, please sign in to theAppleorGoogleapps ORclick herefor the desktop version.

Long-stem alfalfa hay can help buffer stomach acid. | iStockQ: My horse was recently diagnosed with gastric ulcers, and my veterinarian recommended we work with an equine nutritionist to ensure his diet supports his recovery. What diet changes could help a horse being treated for gastric ulcers?A: Building a team with both your veterinarian and equine nutritionist is a great way to make sure your horse has well-rounded support while recovering from gastric ulcers. When adjusting his nutrition program, keep in mind the type of gastric ulcers your horse has.Horses can develop two distinct types of equine gastric ulcers: squamous and glandular. Squamous disease is closely tied to forage intake and dietary management, whereas glandular disease is more often linked to stress.Forage for Horses With Gastric UlcersWhen building a nutrition program, especially for horses with squamous disease, start with the forage. Your horse should consume about 2% of his body weight in hay daily, and you should schedule his feedings in a way that prevents fasting periods. Many horses will do well on free-choice access to hay, but slow feeders can be helpful in some cases to stretch the daily hay allowance until the next feeding.Owners often overlook hay cleanliness when feeding free-choice hay. If you feed hay on the ground, whether in your horses stall or paddock, it can get dirty, making your horse less likely to eat it. This creates fasting periods and increases the risk of squamous ulcers.Additionally, if you give your horse his last feeding of hay at night check and hes eaten all the hay by morning, youre not providing free-choice hay. You might need to increase the amount of hay he gets or use a slow feeder overnight.Beyond the amount of forage, the type of hay can make a difference. Alfalfa hay has been shown to be a great gastric buffer; therefore, you could consider adding alfalfa to your horses ration. If you can feed some alfalfa before exercise, it might work as a buffer in the stomach during work.Carbohydrate Intake for Horses With Gastric UlcersOnce you have established an appropriate forage plan, evaluate your horses nonstructural carbohydrate (NSC) intake. Diets high in NSCs in the diet can increase a horses risk of developing squamous disease.If your horse eats significant amounts of grain or other high-NSC feeds, reassess whether that level of starch and sugar matches his workload. For horses with a history of squamous disease, replacing some NSC calories with digestible fiber or fat can help reduce dietary risk factors.Nutraceuticals for Horses With Gastric UlcersWith guidance from your veterinarian and an equine nutritionist, you could add evidence-based nutraceuticals into your horses dietary management program, but this should not be the first step. Address any forage issues and balance the base ration first.When choosing a supplement to support your horses gastric ulcer management and treatment plan, always choose research-backed supplements and consult your veterinarian and an equine nutritionist for help evaluating the product.Take-Home MessageNutritional adjustments remain crucial in the healing process and prevention of equine gastric ulcers, especially squamous disease. Start with a critical evaluation of your horses forage intake and check that his ration is balanced and not providing excess NSC content. Then possibly add a research-backed nutraceutical with guidance from your veterinarian and an equine nutritionist. Do you have a question about equine gastric ulcers? We want to hear from you! Submit your question below. Name(Required) First Last Email(Required) Address(Required) City State / Province / Region Submit your ulcer-related question below!(Required)By clicking submit below, you consent to allow TheHorse.com and Kelato to store your information and use it to communicate with you regarding your question and other services.CAPTCHA Related Content: Equine Gastric UlcersYour Questions AnsweredVIDEO: Understanding Squamous Ulcers vs. Glandular Ulcers in HorsesVIDEO: Preventing Squamous Disease in HorsesVIDEO: Preventing Glandular Gastric Disease in HorsesPROTEK GI: A Smarter Way to Manage Chronic Equine Gastric Ulcers

What to know about this new class of drugs for insulin dysregulation.The SGLT2 inhibitors could help prevent laminitis in insulin-dysregulated horses. | iStockLaminitis due to elevated insulin levels (hyperinsulinemia) remains one of the most serious consequences of insulin dysregulation (ID) in horses.1 While careful diet and management form the foundation of prevention and treatment, scientists are studying a class of drugs new to horses called sodium-glucose cotransporter 2 inhibitors (SGLT2i) to help lower insulin levels. Examples include velagliflozin, canagliflozin (Invokana), and ertugliflozin.Horses with equine metabolic syndrome (EMS) have ID, but so can some horses with pituitary pars intermedia dysfunction (PPID) as well as with certain illnesses or drugs such as corticosteroids.1 For this reason scientists are investigating temporary use of SGLT2i around the time of corticosteroid joint (intra-articular, or IA) injections as ID can lead to hyperinsulemia-associated laminitis (HAL).How Do SGLT2 Inhibitors Work?These drugs inhibit glucose reabsorption in the kidneys, which lowers blood glucose and reduces the need for beta cells in the pancreas to release insulin. In horses they also reduce beta-cell responsiveness to glucose and after-meal glucose concentrations.Researchers found that velagliflozin, the first SGLT2i studied in horses, decreased insulin response in ID ponies to a diet high in nonstructural carbohydrates (NSCs). They also found 36% of nontreated ponies developed laminitis, while no treated ponies did. In a study of moderate to severe ID horses, resting insulin levels dropped in two weeks.2Studies of canagliflozin have revealed similar insulin reductions, laminitis improvement, and decreases in fat deposits and body weight. Some of this work involved horses refractory (resistant) to dietary management alone, metformin, and levothyroxine.2 Veterinarians have also widely prescribed the SGLT2i ertugliflozin either as a tablet (Steglatro) or compounded in various oral forms. In a case series of 51 horses, scientists saw insulin drop significantly within 30 days along with improvements in lameness scores, even though horses stayed on the same low-NSC diet. Nearly all also lost weight, with a mean loss of 16 kilograms (6% of body weight). In a recent survey of owners in the U.K. and Australia, giving ertugliflozin to horses with ID led to marked improvements in quality of life and laminitis lameness.2About one-third of ID horses in another study received pergolide or cabergoline for PPID before SGLT2i therapy, suggesting SGLT2i can be used without negative PPID drug interaction and might serve as an adjunctive HAL therapy for PPID horses.2The FDA has not licensed an SGLT2i for horses, but studies are ongoing toward that goal. It recently licensed velagliflozin for cats.Side Effects and Cautious UseDo not give these drugs to avoid management and diet changes. Short- and long-term effects are still being studied in horses, and serious side effects occur in some horses.The most common negative effects of SGLT2i include an increase in triglyceride levels, cholesterol, lipoproteins, and various liver values. In some horses these changes can be serious. In milder cases lethargy and a decreased appetite might be the only signs. In one study about one-third of owners reported adverse effects,1 including excessive drinking, urination, weight loss, and dullness. Owners have also reported intermittent diarrhea.3 These drugs have been used to treat type 2 diabetes in people but have also been linked to muscle lossa risk we also consider in horses.These side effects highlight the importance of close veterinary supervision, lab monitoring, and dietary management when horses are on SGLT2i.Take-Home MessageManaging ID is complex, and while SGLT2i save lives by lowering the risk of insulin-related laminitis, they fall short of a silver bullet. Long-term success depends on effective dietary and management changes.As an equine internal medicine specialist, I am very excited about this drug class and the chance to prevent HAL and other devastating effects of insulin dysregulation. hReferencesRecommendations for the Diagnosis and Management of Equine Metabolic Syndrome (EMS) and Insulin Dysregulation. Equine Endocrinology Group. 2024.Sundra T, Matthews V, et al. SGLT2 inhibitors: Exploring the effects in humans and horses. Equine Vet Educ. 2025;37:216224.Sundra T, Knowles E, et al. Short-term metabolic responses following treatment with dapagliflozin or ertugliflozin in horses with hyperinsulinemia. In: 6th Global Equine Endocrine Symposium. Ocala, Florida.

Hay that was cut a couple of months later in the growing season will be far stemmier and contain many more indigestible carbohydrates than one cut earlier in the season. | Photo: iStockQ. Recently, a horse at the barn suffered an impaction colic, and the treating vet said the hay might be partially to blame. I board my horse at a facility that grows its own hay. Each year they take one cutting, typically in September, which seems late compared to other farmers in our area who cut hay in June. Does this have something to do with why the vet thought the hay might have contributed to the impaction?A. Im sorry to hear that a horse in your barn suffered a colic and hope the horse recovered without major incident. Impaction colic can be deadly and may be caused by a number of factors, such as dehydration, poorly chewed feed, and poor forage quality. I suspect the veterinarian was concerned about poor forage quality being a potentially contributing factor in this case given the maturity of your hay.As grasses grow, they become increasingly stemmy, developing a strong stem structure that allows the plant to remain vertical. The components in the plant that provide this strength are known as structural carbohydrates and include such carbohydrates as pectin, fructan, hemicellulose, cellulose, and lignin. Structural carbohydrates exist in cell walls and are difficult for horses to digest. In fact, mammals dont create the enzyme necessary to break down the bonds that hold some of these carbohydrates together. This requires microbial fermentation.A portion of every herbivores digestive tract is dedicated to forage fermentation. It contains billions of bacteria that produce the enzymes needed to break apart most structural carbohydrates. However, even the microbes struggle with complex carbohydrates such as lignin, and not all cellulose will be fermented. So forages that are high in these structural carbohydrates will have reduced overall digestibility.This leaves somewhat undigested material to negotiate the flexures (bends) of the large colon. Flexures are locations in the horses digestive tract particularly prone to becoming impaction colic sites. As the relative proportion of indigestible structural carbohydrate increases, overall digestibility decreases and impaction colic risk rises.RELATED CONTENT | Horse Hay Analysis: What are ADF and NDF?The more mature a plant is when harvested for hay, the greater the relative proportion of these indigestible carbohydrates. A hay cut a couple of months later in the growing season will be far stemmier and contain many more of these indigestible carbohydrates than one cut earlier in the season. Not all later-cut hays are bad, though. For some horses, a later-cut hay is actually ideal because it typically contains less starch and sugar and has fewer calories, making it a good choice for easy keepers and horses with insulin dysregulation. The trick is to cut the hay late enough to capture these benefits but not so late as to result in increased impaction colic risk.This is why lab analysis of hay is beneficial. Lab tests can indicate the hays overall digestibility and the content of some of the structural carbohydrate fractions, such as cellulose and lignin. Most forage analyses will include a value for the acid detergent fiber (ADF) and neutral detergent fiber (NDF) content. ADF is a measure of cellulose and lignin, and NDF is a measure of hemicellulose, cellulose, and lignin. You can estimate hemicellulose, therefore, by subtracting the ADF value from the NDF value. Some results give a value for lignin, as well, which is the truly indigestible plant component. As lignin levels increase with plant maturity, cellulose digestibility decreases.Typically, NDF values between 40-50% and ADF values between 30-35% are good for horses. ADF values above 45% have little nutritional value, and if the NDF value is greater than 56%, your horse might not even want to eat the hay. I recommend keeping ADF below 40% and below 35% if feeding broodmares, foals, or performance horses, especially harder keepers.See if you can persuade your barn owners to cut their hay a little earlier. Perhaps get last years cutting tested and check the results. If the ADF and NDF are very high, try to educate

On Feb. 17, a 7-year-old Quarter Horse mare used for racing in Weld County, Colorado, tested positive for equine infectious anemia (EIA). The horse was tested due to exposure to a positive horse in Adams County, Colorado, in December. Two additional horses have been exposed.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About EIAEquine infectious anemiais a viral disease that attacks horses immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.ACoggins test screens horses blood for antibodiesthat are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease,but those that do can exhibit:Progressive body condition loss;Muscle weakness;Poor stamina;Fever;Depression; andAnemia.EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

According to the USDAs Animal and Plant Health Inspection Service, one new vesicular stomatitis (VSV)-positive premises has been identified in Maricopa County, Arizona.Since October 2025, VSV has been identified at nine equine premises in Arizona, as well as in one wild horsefrom the Salt River Wild Horse Management Group in the Tonto National Forest. All confirmed caseshave been vesicular stomatitis New Jersey virus (VSNJV) serotype.The last outbreak of VSV in the U.S. occurred from May 2023 through January 2024, affecting 319 premises across California, Nevada, and Texas. VSV circulates annually between livestock and insect vectors in southern Mexico and only occasionally results in incursion to the U.S.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About Vesicular StomatitisVesicular stomatitis is a viral disease of horses, donkeys, mules, cattle, swine and New World camelids that occurs in the Western Hemisphere. It is named for the characteristic vesicular lesions it causes in the form of blisters, crusts and ulceration of the lips, muzzle, nose, tongue, ears, sheath, teats and/or coronary band. The virus is transmitted by biting midges and therefore is seasonal.Clinical Signs for vesicular stomatitis include:Vesicle formation leading to ulcerative lesions on the lips, muzzle, nostrils and tongue. The tongue is often the most severely affected area.Ulceration of the inner surface of the lips.Crusting of the muzzle, nostrils, and/or inside the ears.Excessive salivation secondary to the oral lesions.Difficulty picking up and chewing feed.Lameness due to painful erosions on the coronary band.Lesions can occur on the udder, sheath and inside of the ear.Lesions can develop secondary infections resulting in slow-to-heal wounds.Animals on pastures are at increased risk of vesicular stomatitis.Initial diagnosis is based on recognition of characteristic vesicular lesions. Infection is confirmed via laboratory testing for serum antibodies and/or virus identification in fluid samples from active lesions. Veterinarians are required to report suspected cases to state/federal animal health officials who will direct sample submission to an approved regulatory laboratory for diagnostic testing.There is no specific treatment for vesicular stomatitis. Best practices include implementing good biosecurity and treating affected horses with pain relievers, anti-inflammatories and supportive care as recommended by a veterinarian.Isolating all affected animals and placing the premise on immediate quarantine is required until all horses have fully recovered and no active lesions are present. The State Veterinarian will work with the local veterinarian to determine and implement necessary quarantine procedures.

Skipping past steroids to enhance joint health in horsesResearch work continues on how to minimize cartilage injury on horses with OA. | Photo: Nichole ChiricoVeterinarians and researchers have made, and continue to make, remarkable progress in understanding osteoarthritis (OA, degenerative joint disease) in horses. We now know, for example, that the horses joint is an organ, and OA affects all the associated tissues. This includes the joints synovial lining, the articular cartilage lining the bones, the layer beneath the articular cartilage called the subchondral bone, as well as the supporting joint capsules and ligaments. Scientists have also described many of the key players involved in the pathogenesis of equine OA that lead to inflammation and degeneration of the joint tissues, such as interleukin-1 (IL-1), tumor necrosis factor- (TNF), and matrix metalloproteinases (MMPs), among myriad others.Regenerative therapies, along with oral non-steroidal anti-inflammatory drugs (NSAIDs, e.g., Bute) and intra-articular (IA) corticosteroids, help manage OA pain while keeping horses comfortable and in competition. Interleukin-1 receptor antagonist protein (IRAP), autologous protein solution, stem cell therapy (from either adipose tissue or bone marrow), and platelet-rich plasma now are all widely available for supporting horses diagnosed with OA.Despite these advances, no treatment has yet halted the progression of equine OA. Researchers, however, continue to explore novel approaches. In the past year multiple groups have tested creative strategies to address this persistent problem in horses, and here well highlight some of the most promising findings.Next-Level Stem-Cell TherapiesWhile using stem cells for OA is not new, Ontario Veterinary College researchers looked at using pooled, ready-to-use equine umbilical-cord-derived (eCB) mesenchymal stromal cells (MSCs). In that study, led by Judith Koenig, Dr med vet, DVSc, Dipl. ACVS, ACVSMR, professor of clinical studies, researchers combined pooled eCB-MSCs with hyaluronic acid (HA; Munevar Luque et al., 2024) to evaluate symptom-modifying effects of this treatment in client-owned horses with naturally occurring OA of the carpus (knee) or fetlock.They cultured and cryopreserved eCB-MSCs collected from healthy Thoroughbred and Standardbred foals. Then they mixed 1 milliliter of cryopreserved eCB-MSCs containing either 10 or 20 million cells with 2 mL HA and injected them into the affected joint of each horse. Control horses received only 3 mL of the HA.Evidence suggests that combining cells from several donors may better reduce inflammation than using cells from just one donor, Koenig says. Recent studies, including our own, have shown that injecting 10 to 20 million umbilical-cordderived stem cells into horse joints is safe, with the higher dose even linked to fewer signs of inflammation. Stem cell treatments for joints can be prepared in different solutions, such as HA or saline. Because HA is routinely used to treat OA in horses and other species, we wanted to compare if adding MSCs to HA can improve outcomes compared to HA alone.Researchers included horses with lameness localized to a single fetlock or carpus by blocking (diagnostic analgesia) and radiographs (X rays). They assessed baseline joint effusion (swelling) and lameness immediately prior to injection and again 24 to 72 hours and three and six weeks after treatment. Owners completed a satisfaction survey 18 weeks after treatment. In total, the team included nine in each of three groups: 10 million eCB-MSCs + 2 mL HA; 20 million eCB-MSCs + 2 mL HA; and 3 mL HA.No significant differences in lameness were observed between treatment groups at either three or six weeks following treatment; however, lameness improved significantly over time within each treatment group, says Koenig. Additionally, lameness grade improved by 0.5 grades in the HA group, and by one full grade in both the 10 and 20 million eCB-MSC groups, she adds.By 18 weeks, eight of the nine horses in the 10 million + HA group returned to the same or higher level of exercise, and seven out of nine in the 20 million + HA group returned to exercise. Only five of nine horses in the HA group returned to exercise. While this difference was not statistically significant, Koening says the small number might have limited interpretation of the results.In addition to improving lameness compared with HA alone, pooled and cultured eCB-MSCs appear safe. Only three horses had minor adverse reactions following treatment, with the most serious occurring in the HA group. All three horses responded to treatment with an NSAID and cryotherapy.In sum, both HA alone and HA plus eCB-MSCs reduced lameness in horses with naturally occurring OA, but horses treated with both HA and MSCs had higher rates of return to athleticism than HA alone. The researchers saw no differences in using 10 vs. 20 million eCB-MSCs.Based on the results of this study, we treated an additional 30 client-owned horses with either 10 million activated (treated to enhance function) cord blood (CB)-MSCs in HA, 10 million CB-MSCs without HA, or HA alone. Koenig says, referring to data that will be published soon. Horses that received 10 million CB-MSCs were four times more likely to return to exercise, while those treated with 10 million CB-MSCs plus HA were 1.5 times more likely than the HA-alone group to return to exercise 18 weeks after treatment.Koenig explains that the main goal of this research is to develop ready-to-use allogeneic CB-MSCs harvested and pooled in the spring when foals are born. Those cells are then expanded, thoroughly tested for bacteria, fungi, and viruses, and frozen in standardized doses of 10 million or smaller. When certain OA cases arise, veterinarians can thaw and inject the cells immediately, avoiding delays in treatment.Anti-TNF- TherapyEmilio De Simone, MV, PhD, professor of animal physiology in the Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, in Argentina, and colleagues recently reported on the beneficial clinical and biochemical effects of using anti-TNF- antibodies in sport horses with OA (Perrone et al., 2025).TNF- stimulates a variety of cells within the joint to release MMPs, which are a group of degradative enzymes, he explains. MMP-2 and MMP-9, in particular, contribute to the breakdown of gelatin and other matrix components, amplifying cartilage destruction. Other MMPs are also involved in this degradative cascade. Thus, treating horses with an antibody that binds to TNF- may mitigate damage to articular cartilage by reducing the activity of these enzymes. Further, studies suggest that anti-TNF- therapy inhibits other proinflammatory molecules such as IL-1.In the first study evaluating the use of anti-TNF- antibodies for treating OA in horses, De Simone created llama-derived anti-TNF- antibodies to inject IA. He hypothesized this therapy would significantly reduce clinical scores, decrease activity of MMPs, and increase concentrations of glycosaminoglycans (GAGs, structural components of connective tissue) in the synovial fluid of horses with OA.He recruited 50 sport horses20 healthy horses and 30 with OA of the intercarpal or intertarsal (hock) joints. He and his team treated the affected joint in the 30 OA horses with 10 milligrams anti-TNF- antibody and assessed lameness and synovial fluid at baseline and on Day 30 of the study.Key findings included:Lameness decreased significantly in the treated horses over the 30-day study period, though the lameness grade remained higher in the treated group than the control group. These results suggest anti-TNF- therapy has potent anti-inflammatory effects in articular tissues.The horses treated generally had chronic OA with mild to moderate clinical signs, adds De Simone. While clinical improvement was evident, the lameness scores of the treated horses never matched those of the control group, which mostly consisted of horses without a history of lameness or OA.Therefore, although anti-TNF- therapy appears to be a very effective anti-inflammatory treatment, it likely does not reverse the existing structural bone or cartilage damage in the joint, he explains. For this reason, combining anti-TNF- therapy with regenerative approaches could be of interest to enhance clinical outcomes.They found GAGs were significantly lower at baseline in OA joints compared to healthy joints. They increased significantly by Day 30 to similar levels as the control horses, suggesting GAGs are preserved in synovial fluid following treatment.They also noted MMP levels decreased significantly in OA horses following anti-TNF- treatment, supporting the hypothesis that anti-TNF- inhibits MMPs.These results suggest that early treatment with anti-TNF- antibodies can reduce the activity of proteases involved in joint degradation in sport horses, says De Simone. This therapy is particularly interesting because, unlike commonly used anti-inflammatory drugs such as corticosteroids, it does not appear to have harmful effects on joint metabolism. In fact, corticosteroids, especially when administered repeatedly or intra-articularly over long periods, can inhibit the synthesis of key cartilage components such as type II collagen and proteoglycans, potentially accelerating cartilage deterioration. Therefore, anti-TNF- therapy offers a promising alternative that may control inflammation without contributing to cartilage damage.In terms of next steps, he says, At this stage, more research is needed before clinical use can be widely recommended. The current findings are promising and support the potential of anti-TNF- therapy as a novel anti-inflammatory approach for managing equine joint disease. However, further studies are necessary to validate and homogenize the results, and efforts should be directed toward reducing production costs to develop an accessible, commercially viable treatment.In parallel, we are currently evaluating the combined use of this therapy with regenerative approaches such as platelet-rich plasma, aiming to enhance both the anti-inflammatory response and tissue repair, De Simone adds.BiomaterialsIA Biomaterials Polymeric biomaterials have garnered great interest in the field of equine OA. In the past few years manufacturers introduced two polyacrylamide hydrogels (PAAG, one 2.5% and one 4%) to the equine market, and both continue to gain popularity. While both are hydrogels, they have two different mechanisms of action. The 2.5% hydrogel has been shown to integrate into the synovial membrane, whereas the 4% product provides surface and boundary lubrication (Pluim and Frippiat, 2025). Researchers on multiple studies have shown positive effects of these products and, according to a recently published survey, eight out of 10 veterinarians reported satisfaction with using these biomaterials (Pluim and Frippiat, 2025).Given the positive results, other groups are looking into additional IA biopolymers to support pain-free movement. For example, in a study out of the University of Bologna, in Italy, Rinnovati et al. (2025) explored using a carboxymethylcellulose (CMC) hydrogel, composed of cellulose gum crosslinked with croscarmellose in a physiologic buffer.The study included 30 horses with lameness due to OA of one fetlock joint. Half the horses received a single IA injection of CMC, while the remaining horses were treated IA with a combination of 12 mg of the corticosteroid triamcinolone and 20 mg HA. Horses underwent lameness evaluations and flexion tests on Days 15, 30, and 90 of the study.The researchers defined treatment success as a minimum of one lameness grade improvement (using the five-point AAEP lameness scale) compared to baseline. Using that definition they saw treatment success of 20%, 75%, and 75% in the CMC group at 15, 30, and 90 days, which means little improvement in the short term but a marked improvement as time passed. In the controls (triamcinolone/HA), treatment success was 90%, 75%, and 8% at 15, 30, and 90 days, suggesting only a transient improvement.The research team reports that CMC appears to act primarily as a mechanical barrier and joint lubricant that might modify the IA environment over time. This could explain the observed lag in treatment effect.Overall, the researchers concluded that the small study has limitations but offers promising clinical results and encourages additional studies.Lauren K. Luedke, DVM, Dipl. ACVS-LA, assistant professor of equine surgery and lameness at Colorado State Universitys Equine Orthopaedic Research Center, in Fort Collins, and her colleagues recently examined a biolubricant called pMPC (poly2) that functions to augment the extracellular matrix of cartilage. They evaluated pMPC using a well-established post-traumatic model of OA in 16 horses.Researchers simulated joint trauma by inducing an osteochondral chip fracture in the middle knee joint of one limb in 16 horses. The other knee served as the control. Fourteen days later they treated eight horses with 6 mL pMPC in the traumatized knee, while they treated the other eight with 6 mL saline. They performed lameness exams and synovial fluid analyses at baseline and then intermittently during the 70-day study. The team obtained radiographs at baseline and again on Day 70 and performed microscopic analyses of the joints on Day 70.OA joints treated with pMPC had mild increases in lameness, effusion, and flexion scores, says Luedke. Further, synovial fluid analyses showed inflammation, and radiographs had significantly higher osteophyte scores in the pMPC treated joints, an indicator of OA. The studied biolubricant, however, did show some chondroprotective effects on microscopy, with lower erosion scores and higher cartilage GAGs.Although the results werent as promising as those of other biopolymers on the market, Luedke says, I think its important to realize that while we collectively refer to these biopolymers as the same, their chemical composition varies significantly, which is why they may have differing mechanisms of action. The pMPC showed significant promise in early murine (mice or rat) models; however we did not appreciate the same response in horses. This may indicate the dose used may need to change, or the chemical composition altered slightly to accommodate different joint environments. The product did demonstrate some chondroprotective effects.Other Uses of Biomaterials In addition to intrasynovial lubricants, biomaterials might also be used in a variety of ways to benefit horses with OA as described by Kim et al. (2025). For example, biopolymers can be synthesized in nanoparticle format to deliver therapeutic drugs or even genes to affected joints.These nanoparticles are most commonly derived from poly(lactic-co-glycolic) acid (PLGA) which is a combination of lactic acid and glycolic acid, Luedke explains. By creating microspheres of PLGA, therapeutics can be impregnated into the nanoparticles. The PLGA degrades over time, therefore the particles slowly release drugs over time, resulting in sustained drug release and long-term effects (e.g., anti-inflammatories).As an example of using the biopolymer PLGA for drug delivery in horses, Luedke referred to a study by Katzman et al. (2024). Researchers at the University of California, Davis, injected horses IA with PLGA microparticles containing 122 micrograms of flavopiridol, a cyclin-dependent kinase-9 inhibitor (stops cells from dividing). The authors reported that horses tolerated the microparticles well, with detectable flavopiridol in the synovial fluid for four weeks after administration.The extended-release microparticle formulation promotes intra-articular retention of the drug, and it may be an alternative to other intra-articular medications for treatment of equine joint disease, the researchers reported.Take-Home MessageCurrent therapies for OA help veterinarians manage the clinical signs such as heat, pain, and swelling. Stem cells, cell-less therapies (e.g., PAAG), combination therapies (e.g., stem cells with HA), and various biomaterials still need further study. Other areas of researchomitted here for space, not importanceinclude microfragmented adipose tissue therapy, mitotherapy, and gene therapy.Cartilage loss is a major challenge in treating OA, as current therapies cannot restore its original structure. So, while therapies support horses with OA and slow progression, they neither fully stop the disease nor restore the joint to its previous level of health.One of our most significant challenges with OA is the loss of cartilage, says Luedke. Cartilage is important to the joint because it offers a smooth gliding surface and impact protection/shock absorption to the weight-bearing portion of the joint. There are no therapies that can regenerate or repair cartilage to its previous structural integrity. With cartilage damage, the inflammatory cascades become predominant, which in turn compromises the cartilage. Therefore, our primary efforts are to mitigate the inflammatory process within the joint to minimize further cartilage injury.This article is from the Research Roundup 2025 issue ofThe Horse: Your Guide to Equine Health Care. We at The Horse work to provide you with the latest and most reliable news and information on equine health, care, management, and welfare through our magazine and TheHorse.com. Your subscription helps The Horse continue to offer this vital resource to horse owners of all breeds, disciplines, and experience levels. To access current issues included in your subscription, please sign in to theAppleorGoogleapps ORclick herefor the desktop version.

Turning involves generating a transverse GRF that pushes the horses body sideways. | iStockGround reaction forces (GRFs) shape every stride a horse takes, influencing balance, posture, and performance. During the 2025 American Association of Equine Practitioners Convention, held Dec. 6-10, in Denver, Colorado, Hilary M. Clayton, BVMS, PhD, Dipl. ACVSMR, FRCVS, professor and McPhail Dressage Chair emerita at Michigan State University, in East Lansing, delivered the featured Milne lecture. In her presentation she outlined how these forces and the horses center of mass govern locomotion and inform decisions in both lameness workups and rehabilitation.Clayton began by defining the three-dimensional GRFs and the summative vector they create. When the hoof presses downward against the ground, the ground pushes back against the limbs with an equal and opposite GRF that can be measured using a force plate, she said.When illustrated, the GRF appears as an arrow indicating the forces size and direction. In each gait the GRF vector follows a consistent pattern. We look at the effects of the GRF in vertical, longitudinal, and transverse directions, said Clayton. The vertical GRF always acts upwards, combating gravity. The longitudinal GRF acts to accelerate, decelerate, or maintain speed, and the transverse GRF works from side to side across the horses body to produce turning.Ground reaction forces generated by the horses limbs produce movements and rotations of the body. All forms of locomotion, from galloping to jumping to dressage, result from GRFs. The GRF-induced vertical motion of the body also causes oscillations (variations in magnitude) in pressure on the horses back and tension in the reins.The Role of GRFs and Center of Mass in a Horses BalanceThe center of mass (CoM), which represents the entire substance of the horses body, follows a characteristic trajectory during each gait, rising and falling in rhythm with the limb movements. During each complete stride of walk, vertical body motion is small. The withers and croup are highest when the forelimbs and hind limbs, respectively, are vertical in the middle of their stance phases (when the foot contacts the ground and supports weight).The CoM movements in the trot, however, follow the opposite pattern in that they are highest in the suspension phases and lowest in the middle of the diagonal stance phases, said Clayton. There are two oscillations per stride in walk and trot but only one in canter, in which the CoM is high during the suspension and low in mid-stance.Lowest point of the center of mass (red dot) in walk (left), trot (middle), and canter (right). | Courtesy Dr. Hilary M. ClaytonThe lowest CoM position coincides with peak vertical GRF. The relationship between GRF and body position is important in relation to understanding asymmetrical movements of the poll, withers, and croup in lame horses, Clayton added.How Do Horses Balance?Clayton said when a horses CoM is above his base of support (BoS), he is in a stable position. But if the CoM moves outside the base of support, the horse will take a step to change the shape or position of the BoS so it includes the CoM.Conformational characteristics that confer good balance and stability include large body mass, a low CoM, which is typically due to having relatively short limbs, and a large base of support with the CoM centrally located.Agility in Equine MovementAgility describes a horses ability to change direction quickly and efficiently. When a horse anticipates a new direction, he might shift his weight that way in advance. This moves the CoM toward the edge of the base of support, making it easier for the horse to move quickly in the intended direction. For example, a Thoroughbred in the starting stalls leans forward to prepare for acceleration when the gate opens.Turning, however, involves generating a transverse GRF that pushes the horses body sideways.The easiest way to do this is for the horse to lean into the turn while the limbs push outwards to generate a turning GRF, Clayton said.For example, in her research shes shown that high-earning cutting horses turn by leaning into the turn, then pushing sideways. In contrast, low-earning horses begin the turn by moving their limbs to the side.Clinical Applications for Equine BiomechanicsClayton highlighted the clinical relevance of this work. Knowledge of GRFs and their effects on the CoM is beneficial for understanding how horses move and the ways in which we can teach them to move with better posture and self-carriage, Clayton said. Veterinarians need to understand normal locomotion as a prerequisite to recognizing changes in the movement patterns that can indicate the horse is lame or has a neurological disease. During recuperation from injury, rehabilitation specialists use targeted exercises to restore the normal movement patterns so that the horse makes a full recovery after injury.Take-Home MessageUnderstanding how GRFs and the CoM work together gives veterinarians a clearer picture of how and why horses move the way they do. By recognizing normal motion patterns across gaits and disciplines, practitioners can better identify abnormalities and guide rehabilitation to help horses develop strength, self-carriage, and agility.