A genetic mutation in the glycogen synthase 1 (GYS1) gene causes PSSM Type 1 (PSSM1). The mutation causes muscle cells to produce glycogen continually. Since it is an autosomal dominant trait, only one copy of the mutation is needed for a horse to be affected.
Is PSSM hereditary?
Yes. Type 1 PSSM is inherited as an autosomal dominant trait. Only one parent needs to pass the genetic mutation to its offspring for signs of tying-up to occur. No matter who is selected as the breeding partner there is a 50% chance or greater that a PSSM1 horse’s offspring will develop the disease.
How common is PSSM in horses?
PSSM is most prevalent in American Quarter Horses and their related breeds (Paint horse, Appaloosa, Appendix Quarter Horse), Draft horse breeds (especially Belgian Draft and Percherons), and Warmblood breeds. The Belgian Draft been shown to have a 36% prevalence of PSSM.
How serious is PSSM in horses?
This is a serious situation, as it can damage the horse’s kidneys if they become dehydrated. Very young foals with PSSM occasionally show signs of severe muscle pain and weakness. This occurs more often if they have a simultaneous infection such as pneumonia or diarrhea.
What cow horse bloodlines carry PSSM?
Polysaccharide storage myopathy or PSSM is a muscle disease that occurs primarily in horses with Quarter Horse bloodlines such as Quarter Horses, Paint Horses, and Appaloosas. PSSM also occurs in other breeds including Drafts, Draft crossbreeds, and Warmbloods.
What are the symptoms of PSSM in horses?
Clinical signs of PSSM range from mild to severe. They include sweating, lameness, sore muscles, undiagnosed lameness, poor performance, and muscle tremors (“tying up”). These may occur with or without exercise. Under saddle, affected horses may be reluctant to go forward or collect.
What do you feed a horse with PSSM?
These low-starch feeds should be fed with good-quality grass hay or a maximum of 50 percent alfalfa hay. Regular turnout for as much time as possible is critical to successful management of PSSM horses. They do not do well confined to stalls or missing days of exercise.
Is PSSM in horses progressive?
The clinical characteristics of PSSM vary between breeds, from muscle pain, cramping and cell damage with exercise, to progressive muscle atrophy. … This mutation results in the accumulation of abnormal complex sugars within skeletal muscle of horses. This form of PSSM is termed Type 1 PSSM.
What is the 5 panel test for horses?
The Five-Panel Genetic Test
These include hyperkalemic periodic paralysis (HYPP), polysaccharide storage myopathy (PSSM), glycogen branching enzyme disease (GBED), hereditary equine regional dermal asthenia (HERDA), and malignant hyperthermia (MH).
What does vitamin E do in horses?
Vitamin E is a fat-soluble vitamin that acts as an important antioxidant for horses. It helps maintain a healthy immune system and supports normal nerve and muscle function. Horses need vitamin E in their diet because they cannot synthesize it endogenously in their body.
What to do if a horse is tying up?
If your horse ties up, here are suggestions of what to do:
- Stop exercising the horse and move it to a box stall. …
- Call your veterinarian.
- Blanket the horse if the weather is cool.
- Determine if the horse is dehydrated due to excessive sweating.
What is PSSM2 horse?
PSSM2 stands for ”Polysaccharide Storage Myopathy Type 2“ and is an umbrella term for multiple muscle diseases with similar symptoms. … If a genetic test for PSSM1 was negative, but a biopsy showed disrupted muscle formation, the horse was diagnosed with PSSM2.
What is horse GBED?
Glycogen branching enzyme deficiency (GBED) is a disorder first recognized by clinicians at the University of Minnesota that causes muscle weakness in Quarter Horse and related breeds. The clinical presentation of this disease is variable. Late term abortion or stillbirth is described for GBED.
What is HYPP?
HYPP is a genetic disease noted by mild to severe episodes of muscle spasms and trembling. HYPP links back to the Quarter Horse sire Impressive. Breeders should refrain from using any HYPP horses for breeding. Lowering diet potassium levels and providing regular exercise can help manage HYPP in affected horses.