Rat lump: urgent?

Question
QUESTION:
Hi,
I have a problem with one of my pet rats, and I need to know if it a serious one, and what I should do.
My pet rat Ralph (about 1 1/2 yrs) developed a huge "lump" on the front of his left arm. It was not there last night before I went to bed, and this morning, when I took them out it was very brief and I did not notice anything. When I got home from work, I took him out and a large, hard lump was on the front of his arm, about the size of a nickel.

He is eating, drinking and defecating like normal, and is walking normally. When I pick him up, or touch the lump, he does not show any signs of being in pain.

He lives with two younger rats (under a year), and they sometimes scrap, but I checked the lump and there is no sign of a cut or anything that could have caused it. Can tumors form that fast? or is in an abscess?

Any advice would help, should I leave it for a few days to see if it subsides, and if any symptoms develop, or does he need immediate attention?  Is there anything I can do for him right away that could help him.
The vets are all closed now but I will bring him in, the only exotic vets are across town, and being a student I can hardly afford it :(...I just need to know is there anything I can do for him now? and is it bad if I wait a few days before taking him in? All 3 of my rats are male, and Ralph has had no medical problems in the past.
The lump is hard, but I have not yet tried a warm compress.
Thanks for your help,
Erin

ANSWER:
Hi Erin


Tumors can appear suddenly, but are usually small, like the size of a pea when we first notice, sometimes a bit larger.  

This sounds more like an abscess and as long as it opens up, which may take several days, you can treat this at home easily. Start with the warm compress if he lets you. You may even notice a crater or even a black scab on it. Pick the scab off if you see this and beware, because this is often what sparks the release of the exudate inside, which is usually nasty pus. It could be green and thick, white and pasty or white or yellow and runny.  It may smell horrible. Just be prepared for anything.  If it does drain, you should help drain it too by pressing from under the base of the lump, and I do mean UNDER the lump because if you press mid way, the pus may go back into the abscess. Once you get the funky stuff out, rinse well with saline solution or simply plain clean warm water and pack the hole with antibiotic ointment.

No matter what though, you do not need to race him to the vets right away. I would give it a few days to see what it is going to do first. Even if its a tumor and you wait a week or more, it wont kill him so dont worry.  Do try the warm compress though. this usually brings an abscess to a head.

let me know what happens, please. Good luck!

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

QUESTION: Thanks for the response!
I tried a warm compress (cloth dipped in warm water and ringed out), he let me do it for about five minutes just sitting nicely until he decided to get impatient and start squirming away.
It's comforting to see he is still doing fine, but the lump is slightly larger(how worried should I be about the size?) and feels quite firm still. I'll keep doing the compress to see if it gets any softer, or if it bursts. Thankfully, I'm not squeamish.
I got a better look at it though, and under the fur saw a faint line that looked like an almost healed cut. Could this be what caused it? or is it only fresh cuts.
Also, for the saline solution, should I use table salt, sea salt or another type, and how diluted should it be?
Thanks so much for your answer!

Answer
Its best to buy the saline at the pharmacy.  Ask the pharmacist for the proper soltuion to use to disinfect wounds.

Some think to buy contact solution but this is not the same strength needed for an abscess.   If you made it yourself you need to use sterile water or sterility is compromised.  Also,  you would want to use cooking salt, not table salt.

Table salt contain silica-type minerals added and you dont really want to put that in the wound.  If you dont have it on hand simply use diluted peroxide, but very dilute, like 3 parts water, 1 part peroxide or it can damage delicate tissues.

OR....you can buy hibicleanse from the pharmacy and make a gentle rinse and use it to clean the wound if and when it does open.

The cut you saw is probably why there is an abscess if that is what were dealing with.   Rats skin contains staph as a normal flora, just like humans do, and when they get cut etc....the bacteria can get in and cause the infection.