It’s likely that the anus is the source of the bad smell if it’s coming from the region at the base of the tail. If you think any of the following problems exist, get veterinary medical attention right away:
Both humans and animals, including cats, experience flatulence on occasion. There can be a digestive issue if your cat is constantly passing gas or smells horrible.
Loose stool can be left behind by diarrhea in the area of the back. If diarrhea persists, the cat might find it challenging to maintain proper grooming. It’s time to visit the vet if your cat has experienced diarrhea for two or more days.
Stool builds up in the colon as a result of constipation, making it difficult for the cat to urinate. Even though the liquid feces can occasionally pass, the hard, impacted stool may not. This can be applied to your cat’s rear end and tends to smell particularly bad. This causes the cat a great deal of discomfort and may occasionally indicate a more serious health problem.