Rabbits/Hay in diet
I have a friend who has a couple rabbits. She has been feeding them just pellets (and maybe some greens?) I know grass hay should make up the majority of the diet with only a small amount of pellets, so I recommended this to her. However, I have read that it is important to make changes in the diet gradually. Is this also true when adding hay to the diet? I know with horses, feeding large grain meals changes the gut bacteria (fiber-digesting bacteria replaced by more starch-digesting bacteria) so that there can be problems with digesting hay, leading to colic etc...or something along these lines. Is this similar with rabbits, or would there not be a real difference in gut bacteria?
Also, since grass hay (and of course fresh water) should always be available, is it important that pellets are still available at all times until limitless hay can be provided?
First off, let me thank you for educating your friend. There are so many misconceptions about rabbit care and it's great to see you taking a proactive step to help spread the knowledge.
You are correct that any diet change should be made gradually in order to keep from upsetting tummies. I would recommend your friend start out with either some orchard grass or timothy hay, adding a small pile in for the first few days, just so their systems get used to it.
I hate to think that the pellets are unlimited, but bunnies should have a consistent food source so I also agree with you on your assumption here. I would recommend that your friend look for a timothy hay based pellet formula to assist in the transition. This will be a healthier option for pellet access until the pellets can be phased out to a small feeding once a day. This is what I use:
Best of luck, and continue doing a great job in spreading the word about proper rabbit care!