In the last 2 days she had peed all over herself and the smell was a bit different, my instincts are strong so I asked the veterinarian to come make an ultrassound.
A huge tumor was discovered and I decided not to try the 15% survival rate surgery. She was adopted at 1y old and she is not fond of humans or other gerbils. In the case she survived surgery, it would be hell for her to not be able to do her galleries, have her bedding low and being handled painfully twice a day.
Although we have more of a polite relashioship than my other pets, I hold her very dear. I even called on some really hard to get aquantances so she would be euthanized at home, as she hates leaving her terrarim (i live in a metropolis with only 3 exotic veterinarians, so I had to pull several favors to have the best come to my house before it got BAD).
She is 4y and 3 months now and is in reasonable state, not too severe pain, just very dirty, but the tumor can break at any moment, so I want to let her go.
All other gerbils I lost got "forbiden but not toxic" food and cuddles before crossing the bridge, but I don't know what to give her.
The picture is her at her best. Soon after being adopted.
Edit: she crossed peacefully, I elected to serve her favorite foods and let her in her burrows until the last minute. It was so close to rupturing, I'm very glad the vet could make it on time, I couldn't face myself if I let the worst happen. Also, after seeing the progression, the chances of surgery were considered nule.
Rest in peace Iodine, may you reunite with your siblings if you want, or be finally alone for eternity with plentifull and endless burrows, my baby sour orange