This article is from the Winter 2003 AFRMA Rat & Mouse Tales news-magazine.

By Carmen Jane Booth, D.V.M.

Mandie McAlister, Lake Worth, FL
Q I have two pet rats at home. One of them we’re pretty sure has gone mysteriously blind. If you have any information to help me in my adventure, I’d really appreciate it.

A Blindness in rats can have multiple causes, but the most common is from retinal degeneration. Retinal degeneration is commonly observed in rats and is probably related to aging as well as environmental factors including light intensity, amount of light per day, light wavelength, temperature, and stress. This is one of the reasons that it is not recommended to house rodents on the top shelf of a multi-shelf rack or to rotate the cages so that no animal is continually exposed to the most intense light.

When I have rats or mice at home, I keep the cage out of sunlight and cover part of the cage with the nest box so that they can choose to be in the light or dark.

Examination of the affected rat by a veterinary ophthalmologist may provide insight to the cause of the blindness.