Aging Like A Boss: Metabolic Diseases

This week Amanda discuss metabolic disorders and how they affect the senior horse, using her own experience with her aging Aggie to illustrate.

One of the scariest times for Aggie and me came between 2008 and 2010. His whole demeanor seemed off … times a million.

His symptoms were random. Odd hoof growth with white line enlargement and increased water consumption and urination pointed to Cushing’s disease, but he shed out early in the spring like always. Insulin Resistance was a suspect, but he had massive weight loss. At the time it was thought that IR horses were always obese. He had long toe/low heel syndrome, but, no matter how frequent our farrier visited, it wasn’t correcting itself. He had a strong digital pulse, but he wasn’t lame. He was lethargic when we worked, but he still wanted to work.

I poured over studies I found in veterinary textbooks and online, specifically those written by Eleanor Kellon, VMD.

Dr. Kellon led a group on Yahoo called ‘Equine Cushing’s and Insulin Resistance Group.‘  Another invaluable resource is ‘Care and Rehabilitation of the Equine Foot’ by Pete Ramey. The book is mostly about hoof care, but there are several chapters written specifically about metabolic diseases.

I suspected that Aggie was suffering from one or more of the commonly known Endocrine/Hormonal Disorders — Cushing’s, PPID, IR, or EMS — but I didn’t know which one. My veterinarian offered an ACTH test to test for Cushing’s, which involves a single blood draw testing for the hormone ACTH, and a dexamethasone suppression test that involves an injection of the corticosteroid dexamethasone, with a blood sample testing for cortisol taken before and 8 to 12 hours after the injection. The test has a huge risk factor — though even that is controversial — since dexamethasone administration can push an IR horse into laminitis. Both tests are plagued with false positives and false negatives.

Although my scientific brain wanted the tests, I opted not to have them. I felt there was too much risk involved. So we solved the problem the hard way, through trial and error.

NOTE: The following is what worked for Aggie and me. It should not be taken as a “fix all” formula. I highly recommend you consult with your veterinarian, farrier, and equine nutritionist to formulate an individualized plan for your horse’s needs.

I did two things immediately, receiving raised eyebrows from many people for both. One, I pulled Aggie’s shoes and started trimming his toes myself once every week — under the guidance of my certified farrier the first few times. Had I known what I was doing, I probably could have stretched the trim frequency to once a month, but I didn’t, so I opted to trim a tiny little bit once a week. I kept the hoof as balanced as possible and I kept the toe pulled back. Secondly, I altered his diet significantly.

Now, almost eight years later, you can walk into any feed store and find a “low starch/low sugar” formula from almost every national brand of horse feed. In 2008, these things simply did not exist or they were brand new and rarely sold. My problem was compounded by the fact that most horses with metabolic issues are categorized as “easy keepers.” It’s often suggested that you feed them hay and a mineral supplement and nothing else, but, remember, Aggie was losing weight!

Another source claimed beet pulp was the way to go. Aggie hated it and was very close to a bout of colic on one occasion.

I had my hay tested. I had his hair tested. I tried a very expensive, very “scientific” supplement based on the hair testing and he refused to eat.

Finally, I found two products that seemed to control his symptoms. One was Triple Crown Low Starch. This feed fit all the criteria I was looking for in a low starch and low sugar pellet, but it didn’t seem to give him much energy. That’s when I happened across Purina Ultium.

Ultium is not marketed with the metabolic horse in mind. It’s described as being made for the “high energy demands of hard-working equine athletes,” but it is low in starch and sugar, high in fat — which helps manage blood sugar spikes — and has added Vitamins E, C and selenium. Mixed with one cup of Cocosoya oil, Aggie bloomed on the Ultium and we’ve been using it ever since.

The other thing that changed about Aggie’s eating habits is his time spent grazing, in spring and fall especially. During those times of year the nights are generally cool and the days are still hot. If temperatures are too cold for grass growth, sunlight during the day is converted into fructan — through a process I won’t even try to explain — and stored in the plant’s stem. This results in the pasture being overloaded with carbohydrates. Here’s an infographic from Kentucky Performance Products that helps explain the process; the Animal Health Foundation also has more resources about the carbohydrates found in pasture grasses.

Aggie has limited pasture time, mostly my front yard for a few hours a day, and is only allowed in the larger pasture when nights are warm. Luckily, we live in Texas so most nights are warm. I venture to guess these symptoms would be much more difficult to manage in a state with actual seasons.

Throughout this entire process, I kept Aggie in work. There were a few days, and even weeks, that he was sore and grumpy. If he only felt up to hand walk, then we hand walked. If he could do more, we did more. I kept him on sand during the transition from shod to barefoot and used hoof boots when necessary. I also encouraged movement by positioning his water trough, hay bag and feed bucket in different corners of his paddock.

In 2010 all of his symptoms mysteriously disappeared. Was it the feed changes? Was it the transition to being sound barefoot? Was it the magnetic poles shifting and the polar ice caps melting? Honestly, your guess is as good as mine. I was lucky in that Aggie’s symptoms were always mild to moderate. He was lucky in that I am an obsessive owner who notices every little tufted hair out of place and hauled him to the vet incessantly.

The Endocrine/Hormonal Disorders — Cushing’s, PPID, IR and EMS — are still relatively new and often misunderstood, though research conducted by veterinarians and feed manufacturers is certainly greater than what it used to be. My advice, as always, is listen to your horse first and the experts second. Proceed with caution and get the best help money can buy.

Tune in next week, when I discuss vision and hearing loss in the senior horse.

Go Riding.