It's the question many of us have had to ask ourselves. I hate it. What kind of quality of life does my horse/pony have? Not sure it can even be answered, but any input is helpful.
This pony came to us about 5 years ago and was a very wonderful pony for our then 6yr old daughter. The past year and a half, she has had deteriorating eyesight and hearing. She is about 30? Could be a little older. She cannot see- AT ALL. We have to lead her in and out of her stall by her head, because with just a lead rope, she will still run in to walls and whatever else is in her way. She cannot hear until you are right up by her- or high pitched sounds. Otherwise, her health is, ok. She has some thyroid issues, but that's to be expected at her age. She isn't "cranky" and will graze in the middle of the paddock. Lately, we will see her pace in a circle, trying to sense the fence maybe? We can tell when she feels "off" or is in any kind of distress, because she will pace. We will then take her into the barn, where she feels safe, I'm only assuming. We were planning to just let her live out her life until the health became an issue. We are wondering, though, if the blindness/deafness is bothersome to her? She seems fine, until we see her pace or call out. She only calls out when she is not acting "normal". She is not in the same paddock as the other two horses because the other paddock has only an electric rope fence. She needs to be in a structured fence. (Learned that lesson the hard way). The smaller paddock she's in won't support all three of them. She doesn't seem to mind, because she's never been one to mind separation. Even when we have put our Walker in with her, she seems to care less. We just don't want her to be living a miserable life while we think she's ok.
Like I said, I'm not expecting black and white answers necessarily, but input is appreciated.