Last spring I bought a horse who I was told was 16 years old. A couple months ago a friend came and was checking her out and said she was more like in her mid 20's judging by her teeth and the Galvine Groove. I told my ferrier about it and he judged her age by her rib spread. Using his fingers measuring between each rib. He said she is more likely between 15 and 18 years. Is anyone else familiar with way of determining age?