Equine Cushing's Disease, also becoming known by its more technical term, pituitary pars inermedia dysfunction (PPID), is a disease that has recently become more common, but there is still much left to the unknown regarding it. Typically, when we think of this disease, the curly, long coat that doesn't shed comes to mind first. However, there can be quite a few more symptoms and signs that will lead to a PPID diagnosis.
If you notice that your horse has a long, curly hair coat, be on the watch for other indicators, such as delayed shedding (my gelding doesn't start shedding until about June!), change in attitude (this is what prompted me to have blood work done), fat deposits, and increased urination. These are the symptoms that I noticed in my gelding, looking back, and just didn't think anything of it at the time. Sam probably developed PPID shortly after he was diagnosed with EPM. At 28 years old, I'm unsure if an earlier diagnosis would have really helped him at all in the long run.
In order to test for PPID in your horse, the first course of action is to have blood work done. Your vet will let you know if your horse's ACTH levels are in the category to be diagnosed with PPID. The most common form of treatment is pergolyde; the most common brand of pergolyde is Prascend. Typically, a vet will prescribe 1 tablet per day. That's what I started Sam on, and he got very, very sick from it. He stopped eating for a whole week, had a high temperature, and was very lethargic. After consulting with my vet, and doing my own research, I found that most horses cannot tolerate a full tablet of Prascend on a daily basis. Instead, we switched to half a tablet per day and he has been doing very well on that dosage.
There is no actual 'cure' for PPID once it has been diagnosed. In order to help prevent your horse from developing a resistance to insulin (EMS, which can also occur simultaneously with PPID), it is important to closely monitor his diet. Limiting sugar, starches, treats, fresh spring grass, etc. are all good ways to limit his intake of sugar. It's also important to note that wounds will take longer to heal (in my experience, I have a hard time treating thrush and getting it to stay away), your horse's immune system will be compromised, and he may not be able to perform at his previous athletic level.
There has been recent research performed regarding a more permanent solution to treating PPID instead of just managing it. Researchers suggest that surgical ablation of the pars intermedia portion of the pituitary gland has been successful in both dogs and humans; however, the procedure would be much more difficult on a horse. Researchers were able to try a different method of reaching the gland, and they felt that it ended up being a relatively simple procedure that would be cost-effective. You can read more about the actual study done and future developments
here.
So what are your thoughts on the topic? Have you dealt with PPID with your horse? What do think of a permanent treatment that would remove daily maintenance, be cost effective, and would be a procedure that the everyday horse owner would have access to?
