EFFECT OF DAYLIGHT LENGTH ON THE BEHAVIOR OF MICE MUS MUSCULUS MOLOSSINUS L.

Fomicheva E. M., Poddubnaya A. A.

The effect of daylight hours on the behavior of mice in an experiment using the open-field test and forced-swim test was researched. The features of the behavioral reactions of mice, their motor and exploratory activity, and their physical performance under different lighting conditions were studied. It was found that under desynchronosis conditions, when exposing mice of the Mus musculus L. species to lighting conditions of 20 light/4 dark and 9 light/2 dark/9 light/4 dark, the psychoemotional state of the mice changes, which is expressed in a statistically significant decrease in the number of visits to the center, wall stands, and an increase in the number of grooming acts, defecation, and urination compared to the control group under lighting conditions of 12 light/12 dark. Evaluation of performance using the forced-swim test showed a decrease in the duration of active swimming, movements from wall to wall, and an increase in the duration of drifts under conditions of both long-term and intermittent dark deprivation. It was concluded that long-term dark deprivation, even taking into account the “break”, leads to negative changes in the behavior of mice and is expressed in a decrease in performance, the appearance of a depressive-like state and disturbances in psychomotor activity.

Keywords:mice, behavior, desinchronosis, dark deprivation, open-field test, forced-swim test