What is this rash?

[kurland]

We have a long haired beautiful hamster who is 5 months, his name is Usagi

The last 2-3 weeks Usagi has been scratching himself a lot and he has developed a rash and lost som fur on is back.

By your experience, is this

1. allergy
2. parasites
3. mites

Photo of affected area


And closeup below, almost looks like tiny skin blisters (they are not wet)

[kurland]

We will take him to the vet.

Besides the rash, he is a happy camper...

[souffle]

What type of wheel do you have and what size? It may be that the spindle it catching on the long coat and causing this. His back should not touch the spindle. It can also rub if he is sitting in the doorway of a wooden house or tunnel. Can you check all his toys for rough areas or wood spikes or nails?

[kurland]

That's a very good suggestion, I didn't think about that at all.

We changed his weel 4 weeks ago into a large model, because he stopped using his smaller one. We didn't notice the rash back then. It took some time before he started to use his new weel. He is running a lot every night now

Looking at the weel now I can't see that he is even near the spindle while running... The weel is quite large

[souffle]

Sometimes with long coats the hair becomes static and stands up and tangles round the wheel. Is there any fur round the spindle at all?

[kurland]

Nope.
Last night I checked when he was running. His back is not even close to the spindle.
He is running A LOT during the night now. I will give it some time since I suspect that the hairloss and red skin was from the previous weel that he had, and that he stopped using (no wonder ) . We didn't notice at first since he has rather long hair...