What is this crusted lump on my cat's tail? Is it feline pox?

This looks most like a sebaceous cyst which is a benign cyst that can rupture or get infected from time to time. However, there are other things that this could be that are not benign. Just to be safe, I’d see the vet for a better examination. He or she may recommend a cytology (poking the mass with a slim needle and looking at the cells under the microscope) to determine if it needs to be removed or just monitored. Best wishes to you and Mamush!

Hi. This appears to be a cyst based on the photo,but hard to say for sure without an exam. These can form in the dermal layer from an over production of oils sebaceous material. This may not be correct based on a photo so I would make an appointment

Thanks for using Petco Pet Education Center, formerly Petcoach! It is very hard to see in these pictures. This could be a benign or malignant growth. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have her evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good night!

This is difficult to picture. At 12 years of age it could certainly be some type of tumor, however I'll add that tail base lesions (hair loss, scabbing) are frequently related to flea infestations, so if you're not using a good quality feline flea product that's a good place to start. If you want to repost your question with a picture of the lesion, we'd be happy to try to help more.

It is difficult to diagnose without seeing the bump but it could be an infection, cyst, mass, or an injury. The best thing would be to have your vet take a look at it to determine the exact cause and best way to treat. He may need an antibiotic, anti-inflammatory, or other medications to treat. Your vet can do a needle aspirate, if necessary, to help diagnose the cause of the bump.

It looks like it could be an injury to your cat’s tail. If he’s allowed outside, he could have gotten into a fight with another cat causing the wound. Cat bites frequently become infected and cause an abscess, so I would have this checked out by a vet today or tomorrow. The vet can clean it up and can give antibiotics as needed. I hope this helps!

Hi there and thank you for using pet coach to address your concern. From the picture it looks as though it Mau be a cyst that ruptured and dried on the fur. I would have this examined by a veterinarian to ensure there is no infection and to help give you a better answer after physically examining ming to give you the appropriate treatment recommendations. I hope this helps guide you in the right direction. Please let me know if you have any other questions or concerns.