Using the Mouse Grimace Scale to reevaluate the efficacy of postoperative analgesics in laboratory mice.

Postoperative pain management in animals is complicated greatly by the inability to recognize pain. As a result, the choice of analgesics and their doses has been based on extrapolation from greatly differing pain models or the use of measures with unclear relevance to pain. We recently developed the Mouse Grimace Scale (MGS), a facial-expression-based pain coding system adapted directly from scales used in nonverbal human populations.

Coding of facial expressions of pain in the laboratory mouse.

Facial expression is widely used as a measure of pain in infants; whether nonhuman animals display such pain expressions has never been systematically assessed. We developed the mouse grimace scale (MGS), a standardized behavioral coding system with high accuracy and reliability; assays involving noxious stimuli of moderate duration are accompanied by facial expressions of pain. This measure of spontaneously emitted pain may provide insight into the subjective pain experience of mice.

An outbreak of Pasteurella pneumotropica in genetically modified mice: treatment and elimination.

A closed breeding colony comprising genetically engineered, wild-type, and stock mice presented with varying degrees of bilateral mucopurulent conjunctivitis and panophthalmitis. The one mouse with unilateral corneal ulceration, a knockout animal, was submitted for necropsy, and bacterial culture samples were obtained from the affected eye and uterus. In addition, ocular swabs from another 12 clinically affected animals, consisting of knockout, transgenic, wild-type, and stock mice, were submitted for bacterial culture analysis.