Hi Dr. Beth,

I have an 11 yr old mare recently confirmed EPSM mod/sev positive from a muscle biopsy. She has had significant muscle loss in her hind end, and I have not been able to build muscle or put weight on her (very hippy looking) for a couple months now. She is in moderate work (5 days a week) 1st/2nd level dressage. Her symptoms are low energy, refusing to come out of her stall and when changing direction across the diagonal she gets "wobbly" in the upper hind end. Bone scan and xrays have ruled out all other problems. She is on free choice hay and grass turnout 8 hours a day. 3 weeks ago I switched her from 4lbs daily Triple Crown Low Starch to 5lbs Ultium split into two meals (www.ultium.com) plus 1 tbsp Body Builder (by Equiade info at www.equiade.com) and 1 scoop of CoolCals 100 (www.performancehorsenutrition). She is also on a vit E and selenium supplement. I am concerned she is not getting the required amount of fat and was wondering what advice you could give on her diet? She is 17.2 and weighs 1580 lbs. Also, do I continue to exercise her?

Hi Mary. I am so glad you have the answer to the problem, and yes I do see some ways to improve her diet. You want to be aiming for at least 1 pound fat per 1000 lbs of horse per day, so about 1.6 lbs fat per day for her. Ultium is 12% fat and so every pound has 1 x 0.12 = 0.12 lb of fat. 5 pounds per day provides 5 x 0.12 = 0.6 lb of fat. But, this comes with other calories that counterbalance some of the fat calories, so you are right to add a concentrated fat source. 1 tablespoon of Body Builder and 1 scoop of Cool Calories won't be providing much extra fat, though. Every cup (8 ounces) of Cool calories weighs 4 ounces and so has 0.25 (1/4) pound of fat. If you gradually increase to 2 cups Cool Calories per day that would be 0.5 lb fat, and you'd have a totoal of 1.1 pound of at per day. Added oil would be more economical than Cool Calories, and every cup of oil weighs about 8 ounces and so has twice the fat (0.5 or 1/2 pound) compared to a cup of Cool Calories. You can use a combination of oil and Cool Calories, though. There are many ways to do get the right amount of fat using the these ingredients, but one would be to continue with 5 lbs Ultium per day (0.6 lb fat), gradually increase to 2 cups Cool Calories per day (0.5 lb fat), and gradually add oil and gradually increase to about 1 cup oil (0.5 lb fat) per day. Good luck, and please let us know how things go!