Stereotypy

Stereotypic behavior occurs commonly among caged mice, but is often overlooked because of their nocturnal activity patterns. Individual mice may display bar­mouthing, jumping, circling, somersaulting, route-trac­ing, and other forms of repetitive functionless behavior. Mice presented to necropsy may continue to manifest these signs. In some surveys, stereotypies occurred in nearly 100% of ICR Swiss mice and 80% of B6 mice. Some of these activities, such as compulsive circling, must be differentiated from vestibular disease.