hi, lately my little filly has been digging holes and licking the mud/ground, shes been drinking LOADS, her skin is verry dry and shes all itchy. her feed: 1 scoop Hi-Fi, 1 scoop pony nuts, 1 scoop bran, garlic, seaweed. Morning and night. she grazes 8am-4.30 she has a hay net every night...