The short days this time of year slow down horses' metabolism. In the wild, this makes total sense and helps them survive the winter while food is scarce. They go into energy-conservation mode and if they have extra blood sugar they make insulin to signal the body to store the energy as fat for later.
But for our horses, this isn't always helpful. Some of them are gifted/cursed with a slow metabolism all the time (they are always the easy keepers that gain weight very easily and have a hard time slimming down). A lot of older horses have a goofed up pituitary gland that seems to think it's winter all the time, so their hormones get even more deranged when the days are short. And for most of our horses, we aren't exercising them to use up sugar and lower circulating insulin.
Why do we care? Elevated levels of insulin and pituitary hormones cause laminitis, or founder if you prefer that word. Every year around the winter solstice through New Years I get called to horses that have laminitis. They are in a lot of pain and the disease is irreversibly damaging their feet. I had three in the last week and I'll tell you about them because they are good examples.
Case A: 14 year old Quart Horse gelding. He has always been overweight on hay alone, and now I’d even call him obese. (He has a really high-quality grass hay though, the kind that looks like you could put salad dressing on it for lunch.) He has never been lame until this new episode of laminitis, which made him sweaty and not wanting to walk at all. His blood sugar is a little higher than normal, his insulin is 3X normal, and his pituitary hormone is 2.5X normal. His treatment is short term bute for pain/inflammation, less of that good hay in a slow feed net, medication for his pituitary gland, and will include exercise after his feet stabilize.
Case B: 19 year old Appaloosa mare. Has already been diagnosed and on treatment for the pituitary disorder (PPID) for the past year and a half and has been doing great, but developed laminitis this week. Her diet and weight are already managed very well, but her pituitary hormone ACTH had crept higher than it should be, and she just needed her pituitary-regulating medication increased. She improved within two days of the medication increase.
Case C: 12? year old pony gelding. He has always been an easy keeper and chubby, but never had laminitis until now. In the summer he gets more exercise pulling cart but the weather and some other circumstances unrelated to him caused him to get time off from driving. He had a very bad Christmas of not even wanting to stand up from such bad foot pain. His glucose was higher than normal, insulin is my new record at 18X normal, but fortunately his pituitary levels were normal. Treatment is short-term bute, switching to lower-sugar hay, eliminating treats, stall rest, Insulinwise (a supplement), and thyroid hormone to speed metabolism and increase insulin sensitivity.
What’s the take home message?
-Foot soreness, laying down, lameness—those kind of symptoms, can be caused by laminitis which is painful and damages your horse’s feet. The earlier it is diagnosed and treated, the better. Call me as soon as you notice these signs.
-Maintain the ideal diet, feeding program, and weight for your horse. I’m here to help.
-So long as your horse does NOT have laminitis, exercise your horse! Keep it turned out. If it stands at the round bale all day, take it for walks. Ride it up and down hills. I suggest not over-doing the lunging because it’s too much repetitive circle work. If your horse is uncomfortable and stiff, aside from laminitis it could be arthritis, which there are good management options for. Even 20 minutes of walking per day has been proven to help lower insulin, so don’t get discouraged if you can’t ride long or frequently. Some exercise is better than nothing.
-Ask me for regular physical exams and ask about bloodwork on older or overweight horses to monitor these conditions and prevent complications.
Clyde, a horse I had whose first symptom of pituitary disease was laminitis that started around Christmas a few years ago.