Why does my chihuahua have spots on her stomach after tumor surgery?

If the darkened skin appeared around where she had a spay incision, it may be that the tissue darkened some during the healing process, she naturally had some darker patches that weren't visible before shaving the area, or you are seeing the spay scar from the incision itself, especially if it was done recently. If the area is bothersome to Zeytin, or is very itchy or rapidly changing in appearance, that could indicate something such as a brewing infection or allergy that should be checked out by your vet.

Inguinal hernias are serious and should always be repaired as intestines can get stuck in there. If it is an umbilical hernia it may or may need to be repaired depending on the size. It is best to have her examined by your vet. They will be able to tell you more after examining her. The black spots are likely normal pigment change of the skin as the dog ages. There is nothing you can give or do to prevent them.

This presentation is likely to be due to a mild superficial bacterial infection (bacterial folliculitis) on the ventral abdomen. Nothing to be extremely worried about as it could be self limiting/resolving. Disinfection may be started at home with very diluted hibiscrub or betadine or salted water baths. Buster collar may be useful as well to avoid any licking/scratching (if any). If signs are not resolving, a check up, appropriate disinfection and possibly antibiotics (oral, topical or in a shampoo formulation) will be then needed to solve the problem. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

It's a little difficult to tell in your picture - it doesn't appear to be raised. If it is a flat area of redness and hair loss it could be a hot spot or superficial bacterial infection. If it is raised it could be a skin growth like a histiocytoma. I would recommend having your vet examine this lesion to determine for certain what it is.

If the swelling came on suddenly, or is continuing to increase in size or discoloration, it is best to have the spot checked out by your vet. Darkening of the skin can also sometimes be caused by actual bruising, metabolic issues, and skin problems, so a complete exam of the area is best. Some tumors such as mast cell, lipoma and mammary tumors can appear as swellings/skin changes on the belly and should be examined by a vet, however these often appear as nodules rather than dirty/discolored areas.

Thanks for using Petco Pet Education Center, formerly Petcoach! The incision looks like it is healing well so I would not be concerned about those dark spots. Those could be normal pigmentation changes. As long as the incision continues to look like it is healing, there is no need to recheck her. Good luck and best wishes!

If the skin is not irritated/itchy and feels the same as the skin surrounding that is not dark in color, I would just monitor the area. We can have changes in pigmentation of the skin in dogs as they age, as well as changes as the result of inflammation. If the area begins to spread, or the skin feels dry/rough in this area, or she is licking, a visit to the vet is recommended.