I do not believe that is actually long enough to determine how well balanced of a meal it actually is. A human being can survive on next to nothing and some rice for a long ass time. It is not optimal and will have some long term effects on your body but you will be okay for a few months. Raise half a litter on strictly rabbit and the other half on what is believed to be more optimal and see the difference when mature. Rabbit is probably a lot better than kibble though.