Updated On September 23rd, 2025
Pet's info: Small Animal | Unknown - Small Animal | Male | unneutered | 1 year and 8 months old | 1lb
My pet rat has a lump on the side of his stomach
3 Answers
Published on April 23rd, 2018
This could be an abscess, a hernia or a tumor. Unfortunately tumors are common in rats, so if this started small and then grew to this size over time, it is likely a tumor. A tumor in this area is relatively easy to remove if you don't let it get too big, as the surgeon needs enough healthy skin to close the wound again after surgery. A hernia can be easily repaired surgically. You can check whether it is a hernia by gently pressing on the lump and if you can make it disappear into the abdomen, it is a hernia. An abscess will need to be lanced and your rat will need antibiotics. I suggest you schedule an appointment with a veterinarian soon.
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Published on November 3rd, 2016
This may indeed be a mammary tumor that is growing very fast all of a sudden. It could have also broken through into the abdomen and caused a hernia, it could also "just" be a hernia, an abscess or a cyst. Please take Joker to your veterinarian for an exam. A tumor can often be removed, and abscesses and cysts can be emptied. Your vet will also give Joker some pain medicine.
1Pet Parents found this answer helpful
Published on May 15th, 2017
This large lump may be a tumor , an abscess or a hernia. Mammary gland tumors are quite common in rats. I would recommend a hands on exam at your veterinarian to determine if it is a tumor or a hernia or an abscess and then to discuss treatment options
2Pet Parents found this answer helpful
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