What do zebrafish prefer? Directional and color preferences in maze tasks

Abstract

Studies regarding the animals innate preferences help elucidate and avoid probable sources of bias and serve as a reference to improve and develop new behavioral tasks. In zebrafish research, the results of innate directional and color preferences are often not replicated between research groups or even inside the same laboratory raising huge concerns on the replicability and reproducibility. Thus, this study aimed to investigate the male and female zebrafish innate directional and color preferences in the plus-maze and T-maze behavioral tasks. As revealed by the percentage of time spent in each zone of the maze, our results showed that males and females zebrafish demonstrated no difference in directional preference in the plus-maze task. Surprisingly, male and female zebrafish showed color preference differences in the plus-maze task; males did not show any color preference, while female zebrafish demonstrated a red preference compared to white, blue, and yellow colors. Moreover, both male and female zebrafish demonstrated a strong black color preference compared to the white color in the T-maze task. Thus, our results demonstrate the importance of innate preference assays involved with the directionality of the apparatus or the application of colors as a screening process conducting behavioral tests (e.g., anxiety, learning and memory assessment, locomotion, and preference) and highlight the need to analyze sex differences.