Polysaccharide Storage Myopathy (PSSM)

Equine Exertional Rhabdomyolsis – Azoturia – Tying Up – Monday Morning Disease
This is a painful condition which can develop shortly after the start of exercise, commonly after some days’ rest.    It damages a horse’s muscle tissue and is considered to be largely the result of  genetic weaknesses. This pre-disposes victims to excessive accumulation of an abnormal form of glycogen (storage form of glucose) in the muscles. This in turn leads to problems with the energy mechanism required for exercise. Harmful waste substances thus produced cause damage to the muscle cells, leading to stiffness of varying severity and in some  cases the leakage of broken protein fragments into the bloodstream. These are excreted in the urine, giving it a very dark reddish-brown colour.
Symptoms include reluctance to move, stiffness or shortened gait and muscle spasms or cramps, with hard, painful muscles (especially the hindquarters). Other signs are sweating, elevated heart and respiratory rates as a result of the pain, anxious expression, shifting of weight from side to side, and standing hunched and tense. Management  afflicted horses should be moved as little as possible, as this can cause further muscle damage. If necessary use a trailer or horsebox for substantial distances. Veterinary advice and treatment is then essential to effect a prompt recovery. There is considerable advice available on-line e.g.
https://en.wikipedia.org/wiki/Equine_exertional_rhabdomyolysis and
https://ker.com/equinews/managing-horses-pssm
Diet needs to be as low in starch & sugar as possible, so avoid feeding cereals such as oats, barley, wheat (bran), & maize. Legumes such as peas & beans should be avoided, as should most forms of molasses. Condensed Molasses solubles (CMS) is safe to use as it only has about 3-4% sugar.  Safe feeds will include chopped forage such as alfalfa and dried grass, together with high energy protein sources such as cooked linseed, soya & copra. Mineral & vitamin supplements will be required, in particular a high level of vitamin E. Care should be taken with many proprietary E supplements as they usually contain selenium which is toxic at the levels required. Pure vitamin E should be used if necessary.
For further advice complete & submit the Nutrition Enquiry form or call John Chapman on 0344 8844 850 /07721 384508 /07807 479495.

Back to menu at top


Copyright Horseheath Nutrition. All rights reserved.
If any images have been inadvertently used without the copyright holders’ permission (e.g. supplied by customers) then that copyright is hereby acknowledged; copyright holders should contact Gravenhorse Feeds at the earliest opportunity so that appropriate arrangements can be made.

%d bloggers like this: