Rabbits can certainly have a decrease in appetite due to stress such as moving. Other causes such as dental disease, underlying discomfort or pain, etc. can also cause a decrease in appetite. I would always advise a physical exam with a veterinarian experienced with rabbits if your bunny is eating less to ensure there are no other causes for his dietary changes. At the minimum, I recommend adding in additional syringe feeding of a complete diet made for rabbits with decreased appetite (Oxbow Critical Care) to prevent further issues. If a rabbit’s food intake decreases, the motility( movement) of the gut decreases. If the intestinal tract slows down too much, GI bacteria normally in the gut can overgrow to levels that can make the rabbit more ill, and can potentially be fatal. In most cases, supportive care such as feeding and additional fluids to rehydrate the rabbit can help resolve the problem, but some rabbits may need more aggressive treatment and tests.
I are always happy to see your bun to ensure he is doing well and help with his further care. Please call if you would like to schedule an appointment.