The University of Minnesota is performing a study on tying up in Morgan horses. One cause for tying up in horses of all breeds is type 1 Polysaccharide Storage Myopathy (PSSM), for which there is now a genetic test that uses blood or hair roots. (For more information about the test, go to www.cvm.umn.edu/umec/lab/Advances_in_PSSM.html.) However, there are horses that appear to have a type 2 form of PSSM, which, at present, can only be diagnosed by muscle biopsy. The University of Minnesota is currently working toward developing a genetic test for this disorder as well.

If your Morgan horse has been tying up and does not have type 1 PSSM, those at the University are interested in discussing the case with your veterinarian. If your horse fits the study criteria, the University may come to your farm to do an evaluation and perform a free needle muscle biopsy. Several affected horses in the same general area are needed to minimize the travel expense. Please send information about your Morgan horse and contact information for your veterinarian to [email protected] or mail it to 225 Veterinary Medical Center, Attention Michelle Lucio, 1365 Gortner Avenue, St. Paul, MN 55108.