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Why is my dwarf hamster losing fur and has lumps under his tail?

Updated on September 23rd, 2025

Pet's info: Small Animal | Unknown - Small Animal | Male

My dwarf hamster, ant, fur has started to disappear over time underneath his tail and there’s two little lumps what do you think is wrong?

2 Answers

Most Helpful Answer

Answered By Lauren Kennedy, DVM

Veterinarian

Published on May 8th, 2018

It is difficult to tell exactly from the picture you provided but I think the area you are concerned with maybe your hamsters testicles. It is normal for testicles to descend and the hair of the scrotum be thinner than the hair on the rest of the body. Depending on the age of your hamster this could be what is going on.

If you would like to post another question or do a consult we may be able to help you further with what is going on. Alternatively, you could take Ant in to be examined by your veterinarian to make sure there is nothing to worry about.

I hope this helps. Thanks for using Petco Pet Education Center, formerly Petcoach.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Dr. Massimo Orioles, DVM, Cert AVP, MRCVS
Veterinarian
Published on April 23rd, 2017
Common causes of hair loss are mites or fungal infestation, allergies and nutritional deficiencies. If the treatment your local veterinarian gave is not effective another check up is required.
Regarding the lump, it needs to be ideally assessed by your veterinarian to have a definitive and specific answer. Usually there are two ways your vet can do that a part from examining it directly during physical examination.
A biopsy can be taken under local or general anesthetic, otherwise a smaller sample through a fine needle can be aspirated (this technique is called FNA= fine needle aspiration).
Your vet may have a straight answer during physical examination.

Please do not hesitate to contact us again on the forum or by requesting a consultation (where you can post pictures ) if you have any more questions or to discuss it any further.
1Pet Parents found this answer helpful

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