Hello all, I’m really in need of some advice here. I have a male fancy rat, he’s about 1.5 yrs old, 800g and not neutered. I realised today that he seemed to have developed a soft lump with a slightly sunken centre and squishy all around, but a little irregular. Easily moved around basically. It’s located just over his right arm. Here’s a photo: He’s very healthy otherwise, eating drinking fine and running around as usual, so no change in that. I’ll try doing warm compresses to see if it maybe is an abscess and if it doesn’t go down and grow more instead, pop or just generally doesn’t improve I’ll take him to the vets next week. My mum suggested it could be lipoma due to the softness and the fact that it’s just near the shoulder? But I’m not sure if they can just randomly appear on not? What could this be? How do I keep an eye on it to make sure it’s not growing anymore?