Comparative analysis of zebrafish fear responses to eight different fish species using 3D locomotion tracking assays

Zebrafish (Danio rerio) are widely utilized in neurobehavioral research due to their translational relevance in studying fear. Eight different fish species and variations were tested to induce fear responses in zebrafish which include one positive control (convict cichlid) and negative control (tiger barb) through a shared environment test. The observation was done in 3D and 2D to assess the impact of dimensionality on the outcome. A single-camera system was used to capture two viewpoints by mirror reflection installed above the fish tank and reconstructed to 3D using F3LA software. Zebrafish showed a similar behavioral response towards P. demasoni and A. heckelii to A. nigrofasciata with some minor differences and lesser alteration by green G. ternetzi during the shared environment test. Meanwhile, B. melanopterus presence made zebrafish have a higher tendency to freeze and higher entropy, similar to anxiety-like response. There is no correlation in behavioral alteration to tested fishes body size. However, a correlation was displayed when testing only the convict cichlids of different ages. Finally, zebrafish color preference was also observed through the use of G. ternetzi with different body colors, preferring orange and red while mostly avoiding green G. ternetzi. The use of 3D observation edges out 2D observation as several important endpoints are obtainable only from certain viewpoints.