History & Background

The Sprague Dawley, derived from the Winster rat, is the most widely used outbred albino in animal research and is characterized by it good temperament, sociability, calm demeanor, and ease of handling. This laboratory rat, first breed by Sprague Dawley in Madison, Wisconsin, is used most frequently in medical research and has aided to increased knowledge in fields such as genetics, learning, pharmacology, toxicology, oncology, and nutrition.


General Information

            Sprague Dawley’s, like most rats, are highly social and enjoy the company of others. Without proper attention and socialization, they can become depressed, develop neurological problems, or aggressive. Rats are intelligent creatures that can be easily trained to do various tasks such as coming when called and even to use a litter pan. Like most animals, rats are prone to health problems including respiratory infections, mites, abscesses and tumors. Therefore it is important to monitor for symptoms related to these health issues such as sneezing or wheezing, scabbing, and abnormal growths.


Questions and Answers

*When do rats sleep?

            Rats neither sleep through the night or through the day, instead they sleep an hour at a time constantly going to sleep and waking up again.


*How much should my rat weigh?

            Female rats can weigh 250-300 grams while males, a bit larger, will weigh from 450-520 grams.


*How long do they live?

            Most rats typically live for a range of 2.5 -4 years


*Why do they make that clicking sound with their teeth?

A happy and contented rat will “brux” by chipping their teeth together it is just like a cat purring.


*What kinds of treats do rats enjoy?

            Rats love fresh vegetables, fruits, healthy cereals and even baby foods



Wikipedia. 2009. Laboratory Rat. January 18, 2009, from   


Rat and Mouse Club of America (n.d). RMCA Rat FAQ. January 18,2009, from http://rmca.org/ 

Harlan Labrotories. 2009.Sprague Dawley. January 20,2009, from http://www.harlan.com/

Ace Animals, inc. 2006. Sprague Dawley. January 18, 2009, from