This usually happens when the bunny is overweight. They stop because they literally can't reach to clean their bottoms. They also can't coprophage which means eating their poo, therefore it gets stuck as they would normally not need to clean this away, they eat it as soon as its coming out. Deffo take him to the vets but if he is chubby you will need to look at his diet I'm afraid. If this is the case, you'll want to get his weight down before the summer to prevent flystrike.

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