A new lump or swelling in rabbits
What this sign can mean and when to act, from House Rabbit Society and RWAF guidance. This is general information, not a diagnosis.
What you noticed is worth a vet's eyes soon. Rabbits are good at hiding when something is wrong, so it's best to have your exotic vet take a look before anything has a chance to progress. Book a routine appointment in the next day or two, and call sooner if anything gets worse.
What it can mean
A new lump or swelling can be associated with an abscess (a walled-off infection, which is common in rabbits and often linked to dental disease), a benign cyst, or a tumour. Rabbit abscesses tend not to drain on their own the way cat or dog abscesses do, so they usually need surgical treatment. A vet visit soon can identify what it is and whether it needs attention.
Source: House Rabbit Society
Other signs to know
Keep your bunny's care in one place
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BunnyChart provides educational information from verified rabbit-care sources. It does not replace professional veterinary care. Always confirm health-related information with your exotic vet.