American Fancy Rat & Mouse Association

This article is from the Fall 2002 AFRMA Rat & Mouse Tales news-magazine.

Beginners’ Corner

Rats Chewing Off Fur on Feet

By Helen Pembrook & Karen Robbins

Q Why would both our pet rats bite off all their fur on their feet?

Rat with chewed patch on shoulder
This rat has a chewed patch off of her shoulder.

A Athletes Paw . . . fur foot fetish . . . they need new socks . . . new shoes . . . naked feet are better . . . fashion. As long as their feet are not irritated or bleeding, or have a flaky look about the skin, I would not worry about it. One rat may just have a compulsion to groom and has picked the feet for some reason. This behavior may be caused by one rat grooming the other in patches, called barbering. Other times it is a rat doing the barbering to themselves. The rat will chew the fur off down to the skin and you won’t see any scabs. They usually chew on themselves on the front legs or belly, though sometimes you will see it on other parts of the body. If the missing fur is on top of the head or an area you know that rat can’t reach, then it is the cagemate with the compulsion. Sometimes pregnant or nursing females will do this to themselves, and once the litter is weaned, they stop. In their case it could be hormones or stress. In the case of non-breeding rats such as yours, it could be from boredom or a nervous/neurosis type of thing. Make sure your rats have a large cage with lots of toys and things to do in their cage and are taken out and played with for a couple hours every day and see if that helps. A lot of times the rat/rats will stop doing this on their own after a short time. Other times they will exhibit this behavior for months. You do have to be careful though in breeding animals, as this trait may be passed down to their offspring.

Pregnant rat chewed fur off belly
This pregnant rat has chewed the fur off of almost her entire belly. It grew back after the babies were born.

Barbering in rats may be similar to “whisker chewers” in mice. This is where usually one mouse in a cage full of mice will suddenly start to chew off all the whiskers of its cagemates. The mouse with the whiskers is the “chewer.” On a rare occasion, a cage of mice will suddenly start to do this and none of the mice have any whiskers, which means more that one is doing this. In mice, this trait tends to be passed down, so you normally want to eliminate the whisker chewer from your breeding program. In the case of multiple mice in a cage “chewing,” the only way you could determine which ones are doing it is to place them one by one in with a mouse that has whiskers to see which one chews the new mouse’s whiskers off.

Having missing/bald patches of fur or no whiskers is not allowed on the show bench, so if it is a show animal, its show career would be temporarily on hold until they stopped doing this compulsion.

They may have mites, but usually if they do, they are also scratching around the ears and face and you usually see scabs. If you are really concerned, take them to a vet that specializes in rodents or exotics and get their opinion. *

Updated March 27, 2015