Aging behavior

Question
Hello Ms. Kalp,

My quarab Red just turned 23 years old this summer. He is a previously abused horse and has always kept me on my toes, which is something I adore about him. Red usually is spooky about certain things such as tacking up (especially bridling-he was beat on the face). But lately he has barely even put up a reaction to this, which was extremely odd. At first I thought this was one of our great days where tacking up was going to be a breeze, but then when we went out for our trail ride he barely wanted to even walk out. A half an hour into the trail he stopped and started shaking. I got off checked him out and my trainer also made sure he wasn't tying up. He then stopped and looked okay. A few more minutes later and he started it again. I called the vet and he ordered a blood test thinking he may have eaten something bad (pastured 24/7) but all came back okay.
Since the weather has been so hot I haven't been able to ride as much but I am noticing he is still very sluggish even when we do ride and still shakes a times undersaddle. Could this be an aging behavior? The vet said the next step is a neurological test, but he did say it could be age. Have you had cases with aging horses having almost sudden behavior changes? Any advice is going to help me greatly, thank you.
Stacy

Answer
Hi Stacy,
         The symptoms that you are stating sound like they could be a neurological issue like EPM or Encephalitis rather then and age issue. If the Vet has run a full blood panel then the next step would be to pul some spinal fluid.

Please let me know what happens.

Lisa