The "mouse fitness centre": motor function analysis as part of the general health assessment for mice
S. S. Arndt, D. Surjo and F.J. van der Staay
Anatomy II, Cognitive Neurobiology, University of Cologne, Cologne, Germany
An assessment of the animals' general health status should precede any behavioral testing of transgenic or knockout mice. Using a series of test systems, we routinely perform a pre-screening on gross behavioral abnormalities. Such behavioral deficits must be detected to allow an interpretation of test results obtained with e.g. cognition tests. Only healthy animals will be able to meet the physical requirements of many standard behavioral tests. If they prove unable to meet these requirements, special cognition tasks must be selected which do not depend upon the compromised sensory and/or motor functions.
One of the first general health assessment routines (Irwin 1968) evaluated the response of mice to psychoactive drugs. It can also be used to assess the general health of mice and includes, among others, body positon, bizarre behaviors, transfer arousal, locomotor activity and respiration rate. Another test battery, the SHIRPA protocol, is subdivided into three levels of observation. This protocol consists of preliminary observations, such as sensory and muscle functions, autonomic functions, lower motor neuron functions, exploratory behavior, histology, biochemistry and physiological measurements. Taken together, these tests provide a very detailed picture of the animals' general health status.
To allow a quick and simple assessment of one important general health factor, namely motor functions, we developed a multi-task testing apparatus called the "mouse fitness centre". Intact motor functions are a prerequisite for the execution of more complex behaviors. Therefore, the motor abilities of mutant animals should be measured before additional, more sophisticated tests are performed. The fitness centre consists of eight tests (vertical pole, placing response, footprint pattern, horizontal wire, gimp, grip strength, inclined grid and upside-down grid), allowing checks for several gross behavioral dysfunctions. The test apparatus is installed on the so-called 'basis', allowing the mice to perform all motor tests in a row. In this way, testing is less time-consuming and less stressful for the animals. Furthermore, all necessary adaptations of the apparatus for the next test are guided by the basis and defined in a standard protocol, which must be strictly applied. The tests are run in close succession: modifications of the test apparatus mean that pauses between tests are reduced to a minimum. This system has been developed to help realise the idea of a standardized testing system.
Paper presented at Measuring Behavior 2002 , 4th International Conference on Methods and Techniques in Behavioral Research, 27-30 August 2002, Amsterdam, The Netherlands
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