This will need to be tailored to your individual horses needs and abilities. Horse Ownership Once inside the cell the muscles of PSSM horses make much more glycogen than a normal horse due to a mutated (overactive) enzyme called glycogen synthase. Muscle Biopsy: PSSM can be diagnosed based on microscopic evaluation of a muscle biopsy in horses over two years-of-age, however, a definitive diagnosis of the type 1 form of PSSM requires genetic testing. 52nd Proc American Assoc Equine Pract 2006;53:340-346. Some affected horses, however, do not exhibit any clinical signs. The success of the management of EPSSM is mostly based on the correct and, Regular exercise is the best way to prevent and manage PSSM in horses. Ribeiro W, Valberg SJ, Pagan JD and Essen Gustavsson B. If you immediately decrease starch and add fat without the horse needing the extra calories the horse will become obese and this will cause a whole new set of problems. However, this condition is not limited to Quarter Horses, and other horse breeds are also at risk. This article will describe the signs and symptoms of PSSM and the two different types, explain options available to veterinarians to diagnose PSSM, and outline the use of diet in . }). 11.5% were Draught breeds. Update: PSSM in Horses - Kentucky Equine Research The glucose is used for the production of energy within the cell by catabolism. Breeding and foal care The glycogen deposited in the cells is used for energy production. Thus, this mutation isn't attributed to any given stallion or pedigree within a breed. Many horses achieve acceptable levels of performance, but some cases prove extremely difficult to manage. Type 1 Polysaccharide Storage disease (PSSM1) is a potentially life-threatening glycogen storage disease (glycogenosis) that affects skeletal muscles. Horses with PSSM can exhibit symptoms without exercise. A recent study did not find a significant association between the commercial genetic test variants P2, P3 (a and b), and P4 and horses with a diagnosis of PSSM2 or MFM based on histopathology (the gold standard for evaluation of muscle disease). However, with proper management and care, horses with PSSM can live long and healthy lives. 2009 Mar;179(3):336-47. Required fields are marked *. Approximately 50% of affected horses with PSSM1 show improvement under dietary management alone. When horses stop moving they may stretch out as if to urinate. Healthcare and medication, , Clinical signs of PSSM range from mild to severe. The form of PSSM resulting from the mutation was termed type 1 PSSM. There is no cure for PSSM, but most affected horses can be managed successfully through diet and exercise. This group was created to make it a little easier for mare owners to find stallions who have been tested for genetic diseases. If your horse does tie-up, it is important to call your veterinarian immediately so they can start treatment. PSSM can also be found in Drafts and Draft crossbreeds. In-Depth Muscle Disorders. Our laboratory now distinguishes type 1 PSSM (PSSM1) and type 2 PSSM (PSSM2). Polysaccharide storage myopathy (PSSM1) is characterized by the abnormal accumulation of the normal form of sugar stored in muscle (glycogen) as well as an abnormal form of sugar (amylase-resistant polysaccharide) in muscle tissue. There are cases of PSSM that are not associated with the GYS1-R309H variant. If you are benefited by reading, please share it with your friends who owned horses. The degree to which horses exhibit clinical disease with the PSSM1 mutation varies between breeds. PSSM in Horses - Polysaccharide Storage Myopathy 1 & 2 - SmartPak Equine The urine in such horses is often coffee colored, due to muscle proteins being released into the bloodstream and passed into the urine. Make a Gift to the UC Davis School of Veterinary Medicine, School of Veterinary Medicine - Social Media Hub, VIPERFacultyAlumniFuture Veterinary Medical CenterCampus Directory. When there is an imbalance of electrolytes, it can disrupt muscle function and lead to tying-up. There are other causes for tying-up besides PSSM, including malignant hyperthermia, glycogen branching enzyme deficiency, and myosin heavy chain myopathy, so it is important to rule these out to ensure the horse is treated appropriately. Michigan State University Type 1 PSSM is the form of PSSM caused by the genetic mutation in the glycogen synthase 1 () gene. Vet Clin Equine 34 (2018) 253276. Polysaccharide Storage Myopathy (PSSM) is a chronic muscular condition in horses that comes under the broader heading of "tying up," or exertional rhabdomyolysis. 784 Wilson Road, D202 Diagnostic Approach to Muscle Disorders. If a horse is N/N but is showing signs of tying-up or muscle pain, it is possible that the horse has another muscle disorder which must be diagnosed by muscle biopsy. Insulin can further worsen PSSM because it causes the GYS1 gene to produce even more glycogen. Yes, PSSM in horses can be hereditary. PSSM is a condition that causes the horses muscles to break down, which can lead to pain, stiffness, and lameness. These stallions were probably just tested before the 5-panel was available and have no Impressive breeding and since they were PSSM n/n didn't test for MH. .hs-submit{display: inline-block; color: white;} Check the caloric density of the ration balancer, you may want to use one for overweight horses. One is to feed a diet that is high in calories and low in carbohydrates. It was first recognized in horses with Quarter Horse bloodlines such as Quarter Horses, American Paint Horses and Appaloosas and in draft and warmblood breeds with continental European bloodlines (Belgian and Percheron, for example). McCue ME, Valberg SJ, Lucio M, Pagan J and Roe C. Effect of triheptanoin on muscle metabolism during submaximal exercise in horses. @media only screen and (max-width: 768px) { 4 Quarter Horse Bloodlines to Consider Avoiding - Horsey Hooves 2006 May;43(3):257-69. **This article may not be reproduced without the written consent of the UC Davis Center for Equine Health. It stimulates the muscle to take up sugar from the bloodstream. One theory suggests that horses with PSSM (polysaccharide storage myopathy) are more prone to tying-up because they have difficulty metabolizing glycogen. 2010;236(6):663. The mutation in the PPIB gene results in defective collagen that causes the outer layer of the skin to split from the layer underneath. The condition is known as exertional Rhabdomyolysis. Shortened stride. Note the lack of a uniform texture in the PSSM1 biopsy. The most common signs of PSSM in horses are . Type 1 PSSM is inherited as an autosomal dominant trait. PSSM in horses is the abnormal deposition of polysaccharides (Glycogen) in the horses muscle cell. Equine Vet J. Baird JD, Valberg SJ, Anderson SM, McCue ME, Mickelson JR. An autosomal dominant disease caused by mutation in the ryanodine receptor 1 (RYR1). Photo: Wikimedia Commons. hbspt.forms.create({ PSSM is a progressive disease, which means that it will continue to get worse over time. Stephanie Valberg, DVM, PhD, DACVIMMary Anne McPhail Dressage Chair in Equine Sports Medicine, Department of Large Animal Clinical Sciences East Lansing, MI 48824, Equine Neuromuscular Diagnostic Laboratory. PSSM in Horses: Types, Symptoms, Diagnosis, and Management - The Vet Expert PSSM is caused by a build-up of glycogen in the muscles, which can be caused by a genetic mutation. In addition to grains, you should be aware of the sugar content in your PSSM horses forage. Do not force the horse to walk. Equine Pract. They are painful, stiff, sweat profusely, and have firm hard muscles, particularly over their hindquarters. The Quarter Horse gets its name from its ability to outrun other horse breeds in races of a quarter mile or less; some have been clocked at speeds up to 44 mph (70.8 km/h). With proper management, most horses with tie-up can return to normal activity levels. Researchers have not yet determined what causes PSSM Type 2. Treatment will vary depending on the severity of the episode and may include IV fluids, anti-inflammatory medication and rest. , BEMER horse therapy blankets help to regulate blood flow for peak performance. The unique feature of PSSM is that the muscle cells in PSSM horses remove sugar from the bloodstream and transport it into their muscle at a faster rate, and make more glycogen than normal horses. McCue ME, Valberg SJ. , The muscle biopsy technique identified an apparent glycogen storage disease and the terms PSSM or EPSM and EPSSM were used to describe the condition. Weanlings can be fed 6.5 lbs of Re-Leve and mixed grass/alfalfa hay (8 lbs/day). The total non-structural carbohydrate (NSC) should not be not more than 12% of the diet. Provide small paddock turnout once the horse walks freely, usually in 12-24 hours. Polysaccharide storage myopathy (PSSM) is a disease that results in an abnormal accumulation of glycogen (sugar) in the muscles. Type 1 PSSM is caused by a mutation in the GYS1 gene. Type 1 is caused by a known genetic mutation and a DNA test is available. A genetic mutation in the, Polysaccharide storage myopathy type 2 (PSSM2) also results in abnormal glycogen storage in muscle, but horses do not have the, PSSM1 is diagnosed through the genetic test for the, There are other causes for tying-up besides PSSM, including. The management of Equine Polysaccharide Storage Myopathy includes the combination of diet, exercise, and metabolism of carbohydrates within the cells. How do I know if my horse is having an episode of tying up? Genetic Testing: Whole blood or hair roots can be submitted for PSSM1 genetic testing to the University of Minnesota Veterinary Diagnostic Laboratory (800) 605-8787. The malfunction causes excessive calcium to be released into the myoplasm (the contractile part of a muscle cell). Provide fluids: small frequent sips of water. Many feed companies have low starch fat formulated diets for horses that work for horses with PSSM. Reference: Tryon et al J Am Vet Med Assoc. Firshman AM, Valberg SJ, Baird JD, Hunt LM and DiMauro S. Insulin Sensitivity in Belgian Draft Horses with Polysaccharide Storage Myopathy 2008 Jun;69(6):818-23. Horses with Type 1 PSSM can be identified by genetic testing. Prevalence of polysaccharide storage myopathy in horses with neuromuscular disorders. The glycogen deposited in the cells is used for energy production. Foals that survive to birth generally die or are euthanized within 8 weeks of age. We know that both are the result of the abnormal accumulation of muscle glycogen which is the storage form of glucose in muscles. A review of the diagnosis and treatment of rhabdomyolysis in foals proceedings Am Assoc Equine Pract 2002 pp117-121. The variety of acronyms used are in part related to preferences of different laboratories, as well as to differences in the criteria used to diagnose polysaccharide storage myopathy. Who Are the Members of My Animal's Veterinary Health Team? Over 60% of Percherons and 90% of Belgian Draft horses are affected. Myosin-Heavy Chain Myopathy (MYHM) - UC Davis The following table describes the number of randomly samples horses that tested positive for the PSSM11 mutation out of the total number of horses tested as well as the % of horses that were positive for the mutation (prevalence). Horses with the GYS1 mutation (type-1 polysaccharide storage myopathy, or type-1 PSSM) accumulate abnormally large amounts of glycogen (the storage form of glucose), as well as the abnormal . Most PSSM1 horses are calm and not easily stressed, however, if stress is a precipitating fact, stressful environmental elements should be minimized. It is always important to let your veterinarian know if an animal has tested positive for PSSM1. Please email requests tocehadmin@ucdavis.edu. The abnormal polysaccharide always remains within the muscle tissues and does not decrease in amount over time. Stress can also trigger an episode in a PSSM1 horse. Clinical signs may include reluctance to move, sweating, and muscle tremors, also known as "tying-up". The routine exercise includes walk, lunging, riding, and turnout. Episodes of PSSM usually begin after light exercise such as ten to twenty minutes of walking and trotting. CanStockPhoto/Vanell. Familial basis of polysaccharide storage myopathy and exertional rhabdomyolysis in Quarter Horses and related breeds. The management of Equine Polysaccharide Storage Myopathy includes the combination of diet, exercise, and metabolism of carbohydrates within the cells. There is less evidence-based data available regarding management of horses with PSSM2 than those with PSSM1, but they are often treated similarly. International Conference on Equine Exercise Physiology , Equine Vet J Suppl. In: Current Therapy in Equine Medicine 5. ed Robinson E Saunders, Philadelphia PA, 2003, pp 727-734. Regular exercise is the best way to prevent and manage PSSM in horses. J Vet Int Med 1998;12:173-177. Allele frequencies of inherited disease genes in subpopulations of American Quarter Horses. Get the monthly horse newsletter by email. University of Minnesota Extension discovers science-based solutions, delivers practical education, and engages Minnesotans to build a better future. If additional calories are needed, a low-NSC and/or high fat feed source should be incorporated. She is an established authority in the pet blogging community, and her blog, "Paws and Claws," has been featured in numerous publications. How do I Remove Thompsons Water Seal from Wood? Symptoms of PSSM can vary depending on the severity of the disease, but may include: Muscle stiffness This occurs more often if they have a simultaneous infection such as pneumonia or diarrhea. if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'thevetexpert_com-medrectangle-4','ezslot_6',114,'0','0'])};__ez_fad_position('div-gpt-ad-thevetexpert_com-medrectangle-4-0'); Glucose is the end product of carbohydrate metabolism. For riding horses with type 2 PSSM1, a prolonged warm-up with adequate stretching is recommended. Valberg, S.J., Finno, C.J., Henry, M.L., Schott, M., Velez-Irizarry, D., Peng, S., McKenzie, E.C., Petersen, J.L. Horses should begin small paddock turnout as soon as reluctance to move has stopped. Neuromuscul Disord. The disease results from the accumulation of abnormal glycogen (carbohydrate storage molecule) that can damage muscle cells. Enhanced glucose uptake in horses with polysaccharide storage myopathy (PSSM1). List of STallion's Test Results | Facebook (Credit: Briana Malmquist), April 10, 2018 | 2009 Feb;40(1):94-6. For chronic cases, prolonged rest after an episode appears to be counterproductive and predisposes PSSM horses to further episodes of muscle pain. If both diet and exercise are altered, then 90% of horses have had no or few episodes of tying-up. There is no cure for PSSM, but it can often be managed successfully. High sugar content in hay can trigger a horses insulin response. Vet Pathol. These areas are slow to heal, and many horses with HERDA are euthanized due to slow-healing injuries. The cause of PSSM2 remains unknown, though multiple causes are suspected. Two types of PSSM have been identified, PSSM1 and PSSM2. Tying-up also occurs in other breeds of horses such as Thoroughbreds and Standardbreds, but this form of tying-up has a different cause. 2010 Nov 13;167(20):781-4. Genetic testing is also part of the AQHA 5 panel genetic test and is performed at the Veterinary genetics Laboratory at the University of California Davis. PSSM is a common condition in Quarter Horses, with a prevalence of 40.1%. Exercise: Regular daily exercise is extremely important for managing horses with PSSM1. The amount added is usually between 1/2 and 2 cups. PSSM is a muscle disorder that affects horses. if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[250,250],'thevetexpert_com-banner-1','ezslot_10',116,'0','0'])};__ez_fad_position('div-gpt-ad-thevetexpert_com-banner-1-0'); Polysaccharide storage myopathy is a frustrating and frightening disease to many horse owners. Thus, this mutation isnt attributed to any given stallion or pedigree within a breed. McCue ME, Valberg SJ, Miller MB, Wade C, DiMauro S, Akmand HO, Mickelson JR. Glycogen synthase (GYS1) mutation causes a novel skeletal muscle glycogenosis. Horse Ownership, , Select and feed hay that contains less than 10 percent NSC (sugar). 2018. Medications: There are several medications that can be used to help manage PSSM, including antispasmodics, antihistamines, and tranqilizers. BEMER's research in pain relief for horses is shaping the equine industry. If both diet and exercise are altered, then 90 percent of horses have no or few episodes of tying-up. The sample is taken from the semimembranosus muscle, which is part of the rear limb hamstring muscles. Your veterinarian can prescribe the best medication for your horses needs. Make sure to provide ample turn out and exercise for your PSSM horse. Park, H.B Marklund, S. Jeon, J.T , Mickelson J.R. Valberg S.J, Sandberg K, and Andersson L. Molecular characterization and mutational screening of the PRKAG3 gene in the horse. All rights reserved. .hs-main-font-element{color: #29353d} Muscle glycogen concentrations in affected horses are up to four times greater than in normal horses. The effect of varying dietary starch and fat content on creatine kinase activity and substrate availability in equine polysaccharide storage myopathy J Vet Int Med 2004;18:887-894. An important part of the management of PSSM1 horses is daily exercise. This enhances glucose utilization, and improves energy metabolism in skeletal muscle. Myosin-heavy chain myopathy (MYHM) is a muscle disease in Quarter Horses and related breeds that results in two distinct clinical disease presentations, immune-mediated myositis (IMM) and non-exertional rhabdomyolysis. 2018. PDF Polysaccharide Storage Myopathy - AAEP Ensuring an adequate source of quality protein in the diet appears to be important. 1). Once conditioned, some PSSM1 horses thrive with 4 days of exercise as long as they receive daily turn out. Consequently, after light work the horse may experience soreness and muscle cramping. Remove grain. The greatest difficulty in owning a horse with PSSM1 is the time commitment to keep the horse fit and the moderate expense of special feeds. The disease is also known as Equine Polysaccharide Storage Myopathy (EPSM) or tying up of the horse. Valberg SJ, MacLeay JM and Mickelson JR. Polysaccharide storage myopathy associated with exertional rhabdomyolysis in horses. Horses with Type 2 PSSM lack the mutation that is specific for Type 1 PSSM. .hs-submit{display: inline-block; color: white;} There is no cure for PSSM, but there are treatments that can help improve the horses quality of life. At present there is not a specific genetic test for type 2 PSSM and there is not conclusive evidence that it is inherited. Type 1 PSSM can be inherited by autosomal dominant traits, which means that only one parent needs to pass on the genetic mutation for the offspring to contract the disease. 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BEMER Equine Therapy for Horses | What You Should Know Finno CM, Spier S and Valberg SJ. The GYS1 gene carries the instruction for the enzyme glycogen synthase. This research determined that the horses had 1.8 fold more glycogen (storage form of sugar) in their muscles, a deficit in energy when they exercised and persistent elevations in serum CK activity with exercise unless fed low starch high fat diet. Of these, 62.9% of them were Quarter Horse-related breeds. Dr Valberg worked with KER and Hallway Feeds (1-859 255-7602) to develop the first of these diets called Re-Leve** . There are several possible theories as to why some horses are more susceptible to tying-up than others. Healthcare and medication .hs-email{max-width: 100% !important; width: 100%; display: inline-block; vertical-align: bottom;} What is type 1 polysaccharide storage myopathy (PSSM1)? Only one parent needs to pass the genetic mutation to its offspring for signs of tying-up to occur. Horses with PSSM1 have deep purple inclusions of an abnormal complex sugar stored in fibers. There is no specific treatment available for EPSSM. PSSM is a disorder that causes muscle cramping in horses from abnormal glycogen (sugar) storage in the muscles. Stanley RL, McCue ME, Valberg SJ, Mickelson JR , Mayhew IG, McGowan C, Hahn CN ,. Daily exercise is critical for managing horses with PSSM. Because insulin stimulates the already overactive enzyme glycogen synthase in the muscle of type 1 PSSM1 horses, selecting a hay with 12% or less NSC is advisable. Equine Vet j. E-pub ahead of print. Breeds Affected: Animal Genetics offers DNA testing and detection for markers identifying horses that could suffer from PSSM in American Paint horses, Appaloosas, Draft Breeds, Quarter horses (horse with quarter horse blood) and Warmbloods. Muscling in on the cause of tying-up. 2023 2007;231(5):746-50. After a confirmatory diagnosis of the disease, you can go for a few managemental procedures to correct the condition in your horse. Type 2 PSSM refers to PSSM symptoms that occur in horses without the known PSSM1 variant. Further, Type 1 PSSM is inherited from both mares and stallions. PSSM is a muscle disorder that affects horses. hbspt.forms.create({ Exertional rhabdomyolysis in Quarter Horses and Thoroughbreds; one syndrome, multiple etiologies. Affects: American Quarter Horses and several other breeds; the percentage of affected horses is unknown. Episodes usually begin after very light exercise such as 10-20 minutes of walking and trotting. Polysaccharide Storage Myopathy (PSSM) is a condition in horses where there is abnormal glycogen storage occurring in muscles resulting in the accumulation of excessive amounts of glycogen and an unusable polysaccharide. PSSM Type 1 and 2 can present the same symptoms but are caused by different issues. MH is triggered by the use of the anesthetic halothane, the muscle relaxant succinylcholine and stress. The symptoms of PSSM include tying-up, cramping, and muscle pain. region: "na1", Polysaccharide storage myopathy is a glycogen storage disorder and is characterized by the abnormal accumulation of the normal form of sugar stored in muscle (glycogen) as well as an abnormal form of sugar (polysaccharide) in muscle tissue. There is a 50% chance that the PSSM1-positive horses offspring will contract the disease, regardless of who the breeding partner is. Muscle biopsies are required to test for PSSM 2. Dranchak, PK, Leiper FC, Valberg SJ, Piercy RP, Carling DC, Molly E. McCue, ME Mickelson JR. Biochemical and genetic evaluation of the role of AMP activated protein kinase in polysaccharide storage myopathy in Quarter Horses. PSSM occurs primarily in horses with Quarter Horse bloodlines, but can also occur in Warmbloods and Draft breeds. . This can cause a hypermetabolic state (increased metabolism) and may result in death. The primary cause of the disease is overfeeding of readily digestible carbohydrates by the horse and genetic factors. The primary cause of the disease is overfeeding of readily digestible carbohydrates by the horse and genetic factors. While a good balance of Omega 3 to 6 ratio may be important for other health reasons it does not appear to impact the response to fat diets in PSSM1 horses. Horses that are managed properly can generally go on to have successful performance careers. If only the diet is changed, researchers have found that approximately 50 percent of horses improve. A mutation in this gene causes the muscle cells to continually make glycogen. 2000;22(8):782-788. Animal Welfare and Advocacy, 2023 AQHA Guidelines and Rules for Drugs and Medications, , There are two types of PSSM. An autosomal recessive disease caused by mutation in the peptidyl-prolyl isomerase B (PPIB) gene. Type 1 PSSM is caused by a mutation in the GYS1 gene and occurs in over 20 horse breeds. Gradually adding up to 2 cups per day. .hs-email{max-width: 100% !important; width: 100%; display: inline-block; vertical-align: bottom;} Hyperkalemic periodic paralysis HYPP is a completely separate muscle disorder in Quarter Horses from PSSM1. Type 1 PSSM is caused by a mutation in the GYS1 gene. Episodes of muscle pain and stiffness can be quite severe, resulting in a horse being unable to stand and being uncomfortable even when lying down. PSSM1 is diagnosed through the genetic test for the GYS1 variant. High fat concentrates should be used as alternative energy sources in exercising horses. These signs are most commonly muscle stiffness, sweating, and reluctance to move in conjunction with increased serum creatine kinase (CK) activity. The dietary recommendations based on total daily calorie intake are provided in the table belwo to help nutritionists select the most appropriate feed/. Polysaccharide Storage Myopathy (PSSM) | EquiSeq Valberg, S.J., Finno, C.J., Henry, M.L., Schott, M., Velez-Irizarry, D., Peng, S., McKenzie, E.C., Petersen, J.L. This can be performed on hair or blood samples. Horses with mild or moderate cases of PSSM, with proper management, can return to normal performance. By definition horses with PSSM1 have a distinctive genetic mutation in the gene. This disorder causes the horses body to abnormally store or store too much sugar (glycogen) in the muscles. Increase in Creatine Kinase enzyme in blood and urine. Thousands of horses have been identified with tying-up associated with polysaccharide accumulation in muscles. .actions{margin-top: 10px; margin-bottom: 0px;} Insulin sensitivity and skeletal muscle glucose transport in Equine Polysaccharide Storage Myopathy. Plain water should always be available as an alternative. The knowledge on the condition, how it occurs, the signs, and the mode of correction will reduce the owners tension. How to Feed a Horse with Polysaccharide Storage Myopathy (PSSM) The signs are most often seen in horses when they are put into initial training or after a lay-up period when they receive little active exercise.