Blood under skin on rat tumor

Question
QUESTION: Hello,
I have a two year old pet rat who within the last couple of weeks has developed a quarter sized tumor on his lower abdomen. Earlier today I noticed that the tumor had a large blackish spot on the bottom. I just took him out of his cage and there is a hard scab on the bottom of his tumor where the black spot was. Oddly enough when I tried to clean it up with water non of it came off, and after further examination I realized that it is underneath his skin.

Thankful for any advice you have to offer,
Jerry

ANSWER: Sounds like necrotic  tissue. Is this mass open or solid?  Can you show me a photo of it?

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QUESTION: I think you're right, it has developed a slight "rotten egg" smell. It seems to be solid. The odd thing is that he's on anti-biotics right now, so shouldn't that prevent this from happening?

ANSWER: How does it look now? I havent heard back so I assume it has cleared up or since, has at least drained?

---------- FOLLOW-UP ----------

QUESTION: It spurted a whole lot of pus and is now healing over and looking pretty good. I might still take him in to the vets though, just to check on him.

Answer
I had a feeling it was an abscess which is why I asked about the odor.
Meantime, keep it clean and if it left a little "hole", pack it with some antibiotic ointment. He may lick it and thats ok...just as long as it was able to penetrate in the tissue..for at least 5 mins or so.  Keep him busy at least for a few minutes., if you can.  LOL

Before you know it, it will be all closed up. The necrotic tissue you saw earlier was the part of the tissue that had died from the infection. Once it became thin enough....blosh...out it came. I am sure the odor was pretty rough too.  As for the meds stopping it....not always. The type of medication needs to be able to penetrate through the abscessed tissue and some drugs are better than others. I like penicillins in cases like this.  Taking him in to the vet is a good idea for peace of mind, I never discourage people from doing it. However, if someone asked if they could pass up the vet visit when a rat has an abscess, for the most part, as long as it opens up and drains and you help keep it clean and it is healing well, you cant save your money for some other time that is sure to come, unfortunately.

Either way, your a good rat owner for taking so good care of him!!