Natural Colour Preference in the Zebrafish (Danio rerio)

The zebrafish (D anio rerio), traditionally used in genetics is now becoming increasingly popular in behavioural neuroscience. Zebrafish is a small teleost (bony) freshwater fish originating from northern India, used worldwide in research in most stages of development from embryo to adult. While, a couple of papers on zebrafish related to visual colour discrimination and learning have been published [1, 2], its natural colour preference has received little attention [2]. Of particular interest is the receiver bias towards a specific colour. Natural colour preference towards a specific colour may lead to changes in visual discrimination learning, memory and decision making of an animal. Zebrafish has been shown to have colour vision with peak absorbance in ultraviolet (362nm), blue (415nm), green (480nm) and red (570nm) [2]. In the present study we used four different colours (red, yellow, green and blue) to test the natural colour preference of zebrafish. A conditioned place preference (CPP) apparatus using six different colour combinations of gravels was used to measure the time spent in each coloured compartment. This study might be helpful in developing further colour based learning and memory paradigms in zebrafish.