Expectations: It is important to note that a horse diagnosed with PSSM will always have an underlying predilection for muscle soreness and the best that can be done is to manage horses to minimize clinical signs. With adherence to both the diet and exercise recommendations about 70% of Warmblood horses show notable improvement in clinical signs and many return to acceptable levels of performance. There is, however, a wide range in the severity of clinical signs shown by horses with PSSM; those horses with severe or recurrent clinical signs will require more stringent adherence to diet and exercise recommendations in order to regain muscle function.
Re-Leve®** by Hallway Feeds (www.Re-leve.com) In Minnesota, Re-Leve is carried by Assurance Feeds\Phone (651) 463-8041. Developed with University of Minnesota researchers,
Re-Leve is the only feed proven to be effective for PSSM and is good for finicky eaters. Starch content is low (9.0% by weight) and fat content high (12.5% by weight). Additional selenium should not be fed. Two forms of Re-Leve exist.
Re-Leve original is for hard keepers needing more concentrate to maintain body weight. Feed 8-10 lbs for thin horses or horses in heavy work
Re-Leve Concentrate is best for many PSSM horses that are easy keepers 3-5 lbs fed for light to moderate work For overweight horses, work with your veterinarian and avoid excessive fat supplementation.
One approach would be to reduce hay to 1% of body weight and feed 1-3 lbs of Re-Leve Concentrate. For growing horses: Weanlings: 6.5 lbs Re-Leve® and a mixed grass/alfalfa hay (8lbs per day) Yearlings: 8 lbs of Re-Leve® and a 50-50 alfalfa/grass hay (9 lbs per day).
(**a portion of the proceeds from the sale of Re-Leve® are directed to Dr. Valberg)
by Purina in the USA: www.purinamills.com. Or Phone 800-227-89416-8lbs per day
Safe Choice® by Nuterna. www.nutrenaworld.com. 6 lbs per day combined with Empower® at 2 lbs/day
UnTi available in Canada is a low starch and high fat feed
There are now several other low starch and high fat feeds available. Please speak to a nutritionist regarding these feeds. The quality of ingredients may vary so make sure you are working with a reputable company. At a minimum they should meet the nutritional requirements provided in Table 1. In general, the starch content of the feed should not be greater than 15-20% by weight and the fat should be greater than 10% by weight.
Blending of individual feeds Fat supplements combined with additional protein/ vitamin/mineral mixes and a fiber base can be custom blended. You may find in the end that this is not a cost saver. Consult with the manufacturer’s nutritionists to formulate the correct blend for a PSSM horse which is specific to breed and level of use using the values in
Stabilized rice bran
EquiJewel® Kentucky Equine Research, Phone 859 873 1988, Fax 859 873 3781, Email
Natural Glo® (rice bran) Alliance Nutrition. Phone 1-800 680-8254 email
, website www.admani.com/Alliance Equine/
Ultimate Finish® by Buckeye Nutrition, PO Box 505, 330 E. Schultz Ave. Dalton, OH 44618.
Phone: 1-800-898-9467 Fax: (330) 828-2309,
Vegetable Oils: Soy oil or Corn oil gradually can be added at 1-2 cups per day to a fiber base such
as hay cubes or alfalfa pellets. Add 600 U of vitamin E/cup of oil per day. Prognosis for PSSM The best indicator as to whether horses with PSSM will be productive athletes is their past performance combined with response to changes in exercise regimes and diet. Genotype or biopsy findings cannot predict future athletic potential. Horses with PSSM will always have a predisposition to muscle soreness and will require longterm management of their condition. Type 1 PSSM is inherited as a dominant trait meaning that 50% of offspring will inherit the condition no matter to whom the affected horse is bred.
Conflict of Interest Statement: Drs. Valberg, Mickelson and McCue own the license for PSSM testing and receive sales income from its use. Their financial and business interests have been reviewed and managed by the University in accordance with its conflict of interest policies. Dr. Valberg receives a portion of the profits of the sale of Re-Leve. Table 1. Nutritional requirements for an average sized horse (500 kg /1100 lbs) with PSSM at varying levels of exertion. Note NSC refers to the soluble sugar + starch. Fructans in forage are not considered in this calculation as they are not considered likely to impact the glycemic index.
Maintenance Light Exercise Moderate
16.4 20.5 24.6 32.8
% DE as NSC
<20% <20% <20% <20%
% DE as fat
15% 15% 15%-20% 20-25%
1.5- 2 % 1.5- 2 % 1.5- 2 % 1.5- 2 %
697 767 836 906
30 33 36 39
20 22 24 26
22.5 33.5 33.8 41.3
33.8 50.3 50.6 62
52.5 78.3 78.8 96.4
1.88 2.2 2.81 3.13
Vitamin E (IU/day)
375 700 900 1000
***** Disclosure of financial interest: Drs. McCue, Mickelson and Valberg are the patent owners for the genetic testing for
GYS1 . A portion of the proceeds from this test will go towards their continued research as well as patent royalties.
This diagnostic report has been authorized by
James E. Collins, DVM, PhD, Diplomate, ACVP, Professor
--- Report ---
Fax Ph (619)9229275
Fax: Prelim: Final: