Got2Gallop- I can completely understand why a BO would not want you graining your own horse. If you are paying her to feed your horse, then it is the BO responsibility to assure that the horse is fed properly. Double feeding can be bad. But not just that, if the other horses see you feeding your horse, they are likely to act out and be harder for the BO to bring in and feed when she is ready. A horse may get hurt or a fence may be broken in the process. If you want to feed your own horse you may want to look into a self care facility or have the horse on your own property.