Behavioural analysis of mouse mutants

Gene targeting and transgene techniques have dramatically increased the availability of mouse mutants generating an increasing demand for behavioural phenotyping. In general, meaningful assessment of the behaviour of a novel mutant requires numerous tests ranging from evaluation of general health status to highly specific tests. Behavioural responses reflect multiple components like anxiety, curiosity, motivation etc., thus, combination of diverse tests in a battery allows more sound interpretation of the behavioural performance as conclusions based on a single test alone.

To facilitate efficient behavioural characterization of novel mouse mutants, a testbattery with particular emphasis on functions of the nervous system and learning and memory was established at the Leibniz Institute for Neurobiology. The aim of this testbattery is a fast in depth analysis, capable to discover even masked phenotypes.

The standard battery includes the assessment of the general health and neurological status, food and water consumption, home cage-activity, motor coordination, exploration, anxiety, spatial and conditioned learning. All tests are conducted without food-deprivation and only mild aversive stimuli are used. Data acquisition and evaluation is performed with state-of-the-art equipment allowing to complete behavioural phenotyping of a new mutant within 2 months. The problem oriented approach allows further the integration of additional hypothesis-dependend tests into the battery. Additional special tests are availble for further investigation of behavioural differences revealed by the testbattery.

The Testbattery:

General Status and Health:

• body weight, coat condition, whiskers
• reflexes, sensory functions, posture
• drinking, feeding, and activity monitoring

motor coordination (cerebellar function, neuromuscular junction):

• rotarod: accelerated and / or fixed speed
• grip strength

exploration, novel environment:

• open field
• holeboard (without food reward)

anxiety - related:

• elevated plus maze
• light-dark-avoidance

spatial learning:

• Morris water maze: hidden platform

conditioned learning, active avoidance:

• shuttle box: light and / or noise as CS

Additional optional tests, which may be included in the battery

• activity monitoring (running wheel)
• motor learning (Rotarod)
• assessment of working memory (Wishaw water maze)
• spatial learning strategies (Barnes Maze)
• One trial learning (light-dark-escape)
• familiarization (odour familiarization test)
• prepulse inhibition (Startle response)
• fear conditioning