I am currently caring for a 20yr old in-foal mare for some friends who will not return for 2 months. Have just found that she has bumps under her hair, mostly just under her tail (around her anus) and down inside her hind quarters. She seems to have been rubbing the top of her tail too as it looks like the hair has broken off.
I have checked to see if I can see any lice, which I can't. Any other ideas what it might be and should I be concerned enough to call a vet, bearing in mind her age and condition.