You can't take the best care of your rabbits if you don't know the difference between healthy and sick. You need to observe your rabbit and stay on top and prepared in case anything should go wrong.
No one knows your rabbit better then you do. Not the vet, not even me (once they have spend an ample amount of time away from me, that is).
Rabbits can go downhill very quickly. It's sad but true. If you only visit your rabbit once a day to feed, your rabbit will not only be unhappy, bored and lonely, but he will also be in danger. Rabbits usually don't use vocal sounds like dogs and cats, to tell us they are sick or in pain. Rabbits are a prey species and conceal their pain and illnesses very well. They need to do that in order to survive in the wild.
The point to this blog? Observe your rabbit(s). Spend time watching them, playing with them, hanging out with them. Not only will this benefit them (and you!), in the long run, rabbits are a joy to watch and quite silly little creatures! They will make you laugh and smile :)