I have a 12yr old QH mare and I have recently discovered that her ascending pectoral muscles are sort of protruding, it’s hard to describe, but I can feel and see the muscles on both sides, it doesn’t seem to bother her at all, I’ve poked and touch them and she doesn’t care, but I’ve never seen that before, is it normal? Her vet is coming out next week for her yearly teeth float but I am now worrying about these muscles and wondering if I should bring this to my vets attention. I’ve never noticed them before and I groom her almost daily so I know I would’ve seen it if she has always had it, she’s not bothered by the cinch when I saddle her but it seems odd to me. I have a gelding also and his same muscles are not protruding at all. Am I overreacting or is this a concern?