What is stud tail in cats, and should I worry?

Stud tail is a waxy, greasy, sometimes crusty buildup near the base of the tail, where a cluster of oil glands sits. It shows up in both neutered and intact cats and is essentially those glands overproducing. Mild cases mostly need gentle cleaning and regular grooming of the area. It matters more if the skin there gets red, infected, smelly or loses hair, which can mean a secondary infection. Keeping the spot clean and the cat at a healthy weight so she can groom it helps keep it from worsening.

When to call a vet: If the tail base becomes inflamed, infected, smelly or bald, have a vet treat it.