chinese dwarf

Question
we have had our hamster about 1 month it is active eating, clean and running about no problem. however it has developed a soft lump at its bum area. it is soft to touch and does not pain it when i touch it. is this just part of it or something to worry about. it looks like it is part of its body and it tail is in th middle of it

Answer
Is your hamster male????  If so, Chinese male hamsters have very large testicles - much larger than Syrian hamsters.  It could be that he's now reaching adulthood and his body has changed.

If the lump looks red/sore/weeping dry and scabby or the colour changes, then I suggest you getting him to your vet to make sure there isn't a tumour (these are rare) or an abscess.  Otherwise, you might find this is just a normal part of his body.  

If on the otherhand this is a female, then I would get her to a vet sooner rather than later to get it checked out as this type of lump in that area would be abnormal.

Regards