American Fancy Rat & Mouse Association

This article is from the Summer 1999 AFRMA Rat & Mouse Tales news-magazine.


Broken Leg; Mass Pops Out; Injured Rats

By Carmen Jane Booth, D.V.M.

Broken Leg

Nick & Christine, e-mail
Q A few days ago, one of our rats, Daisy, must have caught one of her back legs on something as she now limps around and won’t put any weight on it. It’s definitely swollen and she squeals when you touch the surrounding area. If her leg is broken, will it heal with time (a friend’s guinea pig did this) or is it more serious?

A It sounds like she broke her leg. You should take her to the vet and have it looked at to see if anything needs to be done.

Depending upon where the break is and if there is any break in the skin, the leg may be able to heal with just cage rest on soft bedding where there is nothing to climb on. A couple of my rats had closed fractures of their rear legs at the level of the femur (bone between the hip and the knee). Both of mine healed with just cage rest. I subsequently changed the type of cage from one with a wire mesh bottom to a solid bottom cage. If the fracture is closed (no break in the skin or bone is protruding), than most heal without complications with just cage rest. Unfortunately, they do often heal where the leg is crooked if the leg is not splinted. I would note that splinting a rat’s leg can be difficult and they usually chew off the splint. Trying to treat the fracture can be more difficult and stressful to the animal than having the rat live with a crooked leg. If there is a great deal of swelling around the area, than taking the rat to a veterinarian to make sure that there is no infection is a good idea. Rats are very hearty animals and if the leg heals crooked, most do just fine living in a caged environment. If you are at all unsure what is appropriate, take your rat to your veterinarian.

Mass Pops Out

Nancy Ferris, Corona, CA
Q I had an odd thing happen last night with Roger the rat. He had a scab on his shoulder so I soaked it in peroxide. A little while later I checked on him, and it looked like the skin was separated from the scab, which was attached to this round thing just under his skin. I prodded a little more and this hard mass, about the size of a pea came out leaving a hole. It wasn’t attached to anything, it just popped right out. The tissue underneath looked healthy—no pus or any sign of infection. I cleaned it out real well with peroxide. This morning the wound was closing and had a scab forming. I treated it with peroxide again. Any ideas what this thing is that came out? It was white, hard, and fibrous and looks like it has a core to it (like a piece of raw corn or something).

A With out doing histopathology and looking at what this mass was formed out of, it is next to impossible to know exactly what it was. I would however, guess that it was benign, especially if nothing ever grew back at the site. If it is hard, it is probably mineralized.

Injured Rats

Emily Shabaz, Madison, WI
Q I had seven female rats. Two of them died of respiratory disease. One day I looked at the cage of three of my rats and there was blood everywhere! Now two of them have injuries. One’s neck is kinda “chewed up” with dried blood around it. The other has some blood coming out of her butt. What should I do? I clean, feed, and give them fresh water. They seem very active! Thank you for your time!

A If your rats are fighting, then they need to be separated into individual cages. Rats housed in crowded conditions tend to fight. I would guess that the blood is coming from the vulva rather than the anus. Rats with Mycoplasma pulmonis, the leading cause of upper respiratory infections in rats, often end up with a vaginitis or uterine infection which is also caused by M. pulmonis. As far as what to do medically, the injured rats and rat with rectal/vulvar bleeding should be seen by your veterinarian and treated accordingly. There are a variety of antibiotics that are used to help alleviate the symptoms of rats with respiratory infections that may also help the vaginal/uterine infection as well. Please note that there is no cure for infection with M. pulmonis. If the rat with the vaginal discharge is young enough and a good surgical risk, you might consider having her spayed. If the bloody discharge is from the rectum, than she should be examined by your veterinarian, as rectal bleeding is not common in rats and the list of possible causes is long. *

Back to top

Updated March 20, 2014