California Riding Magazine • December, 2011

Questions for Dr. Lydia F. Gray

by Lydia F. Gray, DVM, MA

How much hay should one feed a Morgan/Friesian horse? He is 15.2 hands in height and weighs about 1250 pounds. I have been giving him some remission though more preventive due to his weight being close to 1400 lbs when purchased last august. We have not seen any issues though with foundering. I currently give a joint supplement (again, preventative as no issues have been noted), Vitamin E w/ selenium (for good skin and hair), probiotics (1/2 ounce, again just preventive) and 2 ounces of grain. Am I giving too much supplement? I was also giving him a bale of hay per day (bales weigh between 30 to 35 pounds, alternating between grass and alfalfa hay)? Thank you, Brenda

Dear Brenda,
Congratulations to you for getting some unhealthy weight off your horse! I’m going to make a number of assumptions here, based on the information provided, to help me answer your question:

Assumption #1: Your horse is an “easy keeper” but not diagnosed with Equine Metabolic Syndrome (EMS) or insulin resistance (IR).

Assumption #2: He was overweight when you purchased him but at an ideal weight and body condition score now.

Assumption #3: Your horse does not graze a significant amount of fresh pasture.

If these assumptions are all true, then you could follow the rule of thumb that says feed horses 2% of their body weight each day in good quality forage. Since 1250lbs X 0.02 = 25lbs of hay, a bale of hay per day that weighs between 30 to 35 pounds might be too much. If a bale has 12 flakes in it, and let’s say you’re feeding four flakes three times a day, gradually reduce his diet by one flake each meal until you’re feeding closer to the correct amount. So feed 3/4/4 for a few days, then 3/3/4 for a few days and finally 3/3/3. Also, because changing hay can lead to more serious digestive disturbances (such as colic, diarrhea or laminitis) than changing grain, I don’t recommend alternating between grass and alfalfa hay, but instead mixing them and feeding a bit of both at every meal.

You don’t say what you do with your horse or how old he is, but I think a joint supplement is a good idea for any horse in work, and most senior horses. I looked up the Remission product and the label says “for horses prone to the risk of founder.” It contains several ingredients that you’re additionally supplementing for, such as Vitamin E/Selenium and Probiotics, so I think there is some overlap there. I would recommend speaking with your veterinarian to find out if the amount of Selenium your horse is getting from his hay, grain and supplements is appropriate.

Speaking of grain, you say you give two ounces. I’m going to make another assumption here, that you give him this grain just to mix his supplements in, since this is way less than any bag of fortified grain would recommend for a horse this size. My suggestion here is to find something else to mix his supplements in that has less sugar and starch than grain. You may even want to add a ration balancer or multi-vitamin/mineral supplement to complete and balance his diet. Not only are most of these available in several varieties—depending on the type of forage you give and the age and workload of your horse—but several come in alfalfa or beet pulp-based pellets which would give you something to mix your supplements in. You’re on the right track, you just need to fine-tune things a bit to help your horse stay healthy and sound. Keep up the good work!

Article provided by SmartPak.
Dr. Lydia Gray is the Medical Director/Staff Veterinarian for SmartPak, where she guides research and new product development, answers questions on her Ask the Vet blog, and speaks around the country at various events such as Equine Affaire, Dressage at Devon, and the USHJA Trainers’ Symposiums.