Chinchilla Eating Its Tail

Q: My daughter’s chinchilla, Calven, is eating its tail. Yes, I typed right. The tail is down to 4 inches. The end of it is bloody and then will heal, and then he eats it again. I have plenty of food, water, hay, wood blocks to chew, salt wheels to chew. We have had him for two years, and he just started this. He also just began eating the plastic platforms in his cage. What should I do? Why is he doing this?

A: Without seeing your chinchilla and examining the tail, it would be difficult to tell you exactly why he is eating his tail. There are, though, some common reasons why such a behavior occurs.

Usually, tail chewing occurs because something unusual happened to the tail. The only way your chinchilla “knows” how to “fix” it is by biting his tail. If the end of the tail became injured, such as being caught in part of the cage, this could cause some pain and his response would be to bite and chew the painful area. If the tissues of the tail became infected, trauma can cause infection, so he may be trying to relieve the discomfort by biting at the area. In some cases, even cancer, both benign and malignant, can cause a chinchilla to bite at his tail.

Any disease condition of the nerves that innervate the tail can lead to tail chewing. After a chinchilla has chewed its tail for some time and caused damage, it is sometimes impossible just from looking at the tail to determine the primary problem. Your veterinarian may need to take radiographs of your chinchilla’s tail and possibly some samples of the skin along the tail to get you an answer.

The sooner you take your chinchilla to your veterinarian, the better, because your chinchilla is in obvious discomfort, there may be a serious disease process that is ongoing, and your chinchilla could lose a significant amount of blood by constantly chewing his tail.