I feed Nutrena Naturewise 16% rabbit pellets to my chins. It's pretty much the only good feed I can get here locally that my herd does well on.
Depending on where you are located, you might do better to order from someone who sells supplies on here. With one chin, a 25 pound or a 50 pound bag would be a huge waste. You wouldn't use it up before it was out of the expiration range. Sandi on here sells Nutrena and Tradition, and there are other folks who sell other types of feed as well. I believe you can get Oxbow at Petsmart and Petco, but I don't buy at pet stores, so don't quote me on that. You used to be able to get Oxbow from Oxbow, but they decided they wanted to make more money, so you can't buy it direct anymore.