Neurological Disorders: Marble Burying Assay
The burying of a marble is a natural defense mechanism in mice that occurs under conditions of stress or states of anxiety. The marble burying assay is able to detect phenotypes related to anxiety and obsessive compulsive disorders. In response to novel bedding/environment mice exhibit digging behavior. Marbles serve as means to measure the amount of digging.
Mice are individually housed in a cage filled with 5 cm of novel bedding for a 30-minute testing period. Up to 16 mice are examined during each testing round. Prior to each round, the experimenter evenly spaces 25 marbles across the bedding surface. After 30-minutes, each mouse is returned to its home cage and all marbles 2/3 buried or more are counted. Borderline marbles (~2/3 buried or less) are not included in the data analysis.
Displayed below is a sample graph of how marble burying observations are presented. In comprehensive phenotypic data packages graphs are interactive. Raw or calculated data and statistics can be seen by clicking on points in the graph.
Figure represents number of marbles buried by male and female (left), male (center), and female (right) mutant mice. Number of marbles buried by wild type littermates (green circle), homozygous (red diamond), and recent historical wild type (purple line) mice are plotted against long-term historical values (± 2 standard deviations) for wild type animals (green shading). Recent wild type values are calculated from data collected within 60 days of current measures and long-term historical values are derived from data collected on more than 10,000 wild type mice.