Yes. It's okay and many breeders do it. Moreso for show rabbits than pregnant does, it does have energy that can be good for the does but the oils in it are good for their coats. Unlike regular sunflower seeds (and most seeds) these have thin, easily digestible oily shells so they are fine for rabbits - these are the ONLY type of seed I would give to a rabbit. I've fed the rabbits pretty much any brand (I feed wild birds with it as well so I go through it quickly), just make sure if you are getting ones meant for wild birds they do NOT have "added vitamins" or such - sometimes the more expensive bird feeding ones do. They also work well as treats because rabbits love them.