Baby, my 4 year old rex/mini-rex/lion head/Chinchilla mix has a fairly large lump on her backside -- please help!

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Oct 4, 2018
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Tacoma, WA

I have not posted in a long time, but a week ago, Baby, a very large bunny of mine who turned 4 in April, had a lump on her lower back/rump and it seems to look a bit more swollen tonight as I was cleaning her cage. When I first noticed, I assumed it was from a small bite from her mom or dad, who are in the same pen, so I put peroxide on it and kept an eye on it. Now I noticed a little hole inside of it and it almost appears a bit bigger.

Baby's mom Storm, is half mini Rex, half Rex and her dad Gary (my PFP) is half Lion Head, half Chinchilla. She is about 11 lbs, has an eye injury from when she was a baby (or a birth defect; her eye did not open on day 9 or 10, so I took her to the vet). She is very active, happy, fast and strong and poops a lot. So I do not think she is sick. I moved to a new state in Sept, so I am literally looking for a vet as we speak. Another bunny had a similar issue (not mine) and someone suggested fly strike, but I have not seen any flies in WA State since I left Arizona, which has a ton of flies.

Please help, I will do my best to get her in tomorrow :(


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Possibly a botfly (different than flystrike, which would be an immediate emergency if this is what it was) or an abscess. Either one could produce a lump with a hole in it. There are other possibilities, like a tumor (but hopefully not), but those two seem the most likely to me.

Medirabbit: abscesses

Medirabbit: abscess management

Medirabbit: botfly
Thank you for your response. I finally found a bunny saavy vet, after much calling around, and I am taking her in at 10:30 am Friday (today). I will update this thread, thanks again :)
Picked up Baby from the vet a few hours ago (Evergreen Avian and Exotic Animal hospital), and the doctor confirmed it is a tumor :( He said it is likely benign, but cannot be certain. I ordered them to send it to a lab to confirm or deny it is harmless, but I needed to schedule surgery regardless. If money were not so tight, I would have ordered the check before surgery for peace of mind-- but he was very reassuring that if somehow it is cancer (💔), it is very, very unlikely to have spread outside of the area it is in and he is confident she will be fine since she is still young-ish. I am pretty sad but hoping fot the best. I love my baby girl and remember her being born on 04/14/2019.


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Baby's surgery was today, it went well and she was already very alert when I picked her up. She is eating, drinking, pooping and walking around a lot. I gave her pain meds/anti-inflammatory.

I opted into ordering the hystopath to see if the tumor was benign or not; I should get results in 5-10 days. I will once again update this thread. I hope this will help others as well. I was worried about them putting her under because unfortunately she is a bit overweight, but she lost several ounces since last month-- thanks to a big reduction in pellets and more exercise. Just doing it gradually. ❤️

Thank you all for supporting Baby!
well , we are hoping for the best for bunny baby

glad to read that your reducing the food intake

wish there was some kind of bunny threadmill at where she would get her paw count for the day

makes me womder , at how many paws a day would be considered in burning of bunny calories ?
Finally got the results back for Baby...

Below is the pathologists report; Benign basal cell tumor, skin. COMMENT: These tumors are common in older rabbits. Most are benign, as in this case. Excision appears complete. If you have any questions let me know. I don't suspect it will come back.

Thank you all for keeping Baby in your thoughts. ❤️