If you see a bump or lump on your bunny's cheeks, take him to the vet for a diagnosis. It could be fairly innocuous, or evidence of a life-threatening condition. Let your vet know if your rabbit displays any symptoms of illness, such as lack of appetite or lethargy, which might help pinpoint your pet's problem.
While abscesses in other animals -- and people -- usually burst and drain, that's not true of bunnies. The infection inside a rabbit's abscess, that is a lump of pus underneath his skin, has a thicker consistency than in other mammals, similar to toothpaste. Since rabbit abscesses often result from dental disease, you'll notice a tender, painful swelling on the cheek.
Your vet examines the rabbit's mouth for signs of disease, as well as taking a sample of the abscess to determine the type of bacteria inside it. While your vet might prescribe antibiotics for smaller, less invasive abscesses, larger abscesses might require surgical removal. While abscesses are lanced in other animals, that doesn't always work with bunnies. If the abscess is lanced, it might continue to require regular surgical draining along with long-term antibiotic therapy. The dental issues causing the abscess also require veterinary attention. A constant supply of timothy or grass hay usually provides sufficient fiber to wear down the teeth and prevent dental disease.
According to the House Rabbit Society, warts are the most common causes of bunny lumps and bumps. These are generally caused by the papilloma virus. Most warts are harmless and may disappear on their own. If the wart changes shape or color or continues growing, take your bunny back to the vet.
Although skin tumors on a rabbit's face aren't common, they can occur. The lump could also be a cyst, a sac under the skin containing a semi-solid substance. An X-ray can reveal more information about the lump. Your vet can remove a cyst and perform a biopsy if she suspects a tumor. While the tumor can also be surgically removed, your bunny's prognosis depends on whether the tumor is benign or malignant.
The rabbit disease myxomatosis is always fatal, but the swelling on a rabbit's head appears after other obvious symptoms. Initial signs include conjunctivitis, or inflammation of the eye's mucus membranes. The rabbit runs a high fever and might die very soon. Those that don't succumb right away develop swellings on the face, ears and genitals. This condition cannot be treated or cured.
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