i love rice bran, i really do. but it puts in weight very fast. when i bought my mare, she was about 200lbs underweight. ive had her for... hmm.. about 3 or 4 weeks now and shes put on a good 100lbs. AND shes a horse that works every day. so with a horse that isnt working and is already a little chunky, i probably wouldnt. although as a treat once in a while thats fine, my broodmare gets it every so often as a nice treat. cuz we all know SHE doesnt need any extra weight! sometimes i wonder if she will fit through the stall door!