I’ve had three horses euthanized.
Two were pretty clear-cut and, in fact, one actually died as the vet walked up with the syringe of anesthesia solution. He never did have much use for vets and their syringes and wanted the last word.
The third one was seven, had cervical stenosis from a combination of arthritis that had seriously worsened over a three-year period and unresolvable soundness issues, likely caused, or at least exacerbated, by the cervical arthritis. He was mildly neurologic on the scale (0.5-1 out of 5). I did what seemed to be reasonable to try to fix him and waited to see if it helped, but I pretty much saw the writing on the wall at least a month before we made the final decision. It would have taken a miracle at that point. I had amazing support from my vet (to whom I turned during the horses’ penultimate appointment and said, “is this the right decision?” bc I needed that one final piece of validation), trainers, barn friends, friends from previous barns, family. It was a horrible decision to make and a horrible day when we euthanized him and I felt awful for playing god, yet felt oddly at piece in a way afterwards.