Every winter when she eats out of her feeder she rubs a part of her mane off at base. I know I could get a new horse feeder but not an option this winter. Would I be able to keep the slinky on her when she is out eating or anything other ideas? :)
Is the feeder a hay feeder? If so just toss it. You do not need it and it is better for the horse to eat off the ground. If it is for the horses grain just replace it with a bucket feeder. Cost about $12 at TSC.
I agree with the last few posts. Also you could apply MTG to the areas where your mare is starting to rub her mane, that should help the hair grow back a little quicker, though I don't think it will stop her from rubbing.
Also, does she wear a blanket? If so get her a neck cover to attatch to her blanket. That should cover her mane so she can't rub it. But make sure that it is at lease 1200 denier so it doesn't rip!