Effects of Different Wavelengths from Light Emitting Diodes (LEDs) on Growth and Development in Zebrafish (Danio rerio) Embryos and Larvae

Abstract

Light environment in aquatic habitat is one of the important physical parameters affecting growth and physiology of fish. To investigate the effects of the light on the growth of zebrafish embryos and larvae (Danio rerio), fishes were reared under the illumination of Light Emitting Diodes (LEDs) of different wavelengths including green, red, blue and white. Morphometric, Neuromast Staining with 2-[4-(Dimethylamino)styryl]-1-ethylpyridinium iodide and Polymerase Chain Reaction (PCR) analyses were used to examine the initial development of sensory capacity in this study. In the days 5,6,7 the green light produced the most favorable result. During that time the early larval development, blue light had consistently negative and contradictory impacts on early parameters such as eyes development, egg yolk absorbed and total length. Exposure to certain wavelengths of light can induce gene expression, opn1lw1 detected opsin and (mtnr1ba and aanat2) were active under all four experimental lighting conditions, suggesting that photoperiod treatment (rather than wavelength) entrains melatonin production. Some methods and conditions used in this study may differ from those used in previous studies, such as the light intensity, LEDs specifications between products, and possible differences in rearing technique.