My husband just bought a new horse who is a little on the thin side but we have wormed her and started her out on grain and alfa alfa cubes. She isn't up to what she should have yet at a time.But today I noticed her leaving the hay and chewing on twiggs and even pawing the ground eating what looked like to me just dirt. I was just wondering what would make her do this and leave good quailty hay laying??please some suggestions!!