Marble Burying Test (MBT)

This test measures a possible anxiety-related behaviour of the mouse. The test consists in placing 9-20 (according to the dimension of the cage) glass marbles, evenly spaced in five rows of four, on approx. 5-cm layer of sawdust bedding which is lightly pressed down to make a flat even surface, in a plastic cage. A mouse is then placed in each cage and left for 30-45 min after which the number of marbles buried with sawdust is counted. Over the last decades, the suppression of spontaneous burying of glass marbles by mice has been used as an index of anxiolytic drug action. I.e., in the marble burying test (MBT), acute administration of benzodiazepines and different classes of antidepressants inhibit marble burying. However some non-anxiolytic compounds such as antipsychotics also reduce marble burying. Moreover it has been suggested that marbles do not function as aversive stimuli.