1 بخش شیلات، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان گیلان، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، گیلان، ایران
2 مؤسسه آموزش و ترویج کشاورزی، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران
عنوان مقاله [English]
This study was performed to investigate the interaction effects of astaxanthin and beta-carotene pigments in white and red lights on growth performance and coloration of swordtail, Xiphophorus helleri. A total of 180 swordtail with an average weight of 1.4 ± 0.1 g with three diets containing 150 mg/kg astaxanthin, 150 mg/kg beta-carotene and a diet without additive pigment and treatments in contrast to white and red lights with light intensity of 1200 lux was fed in 6 treatments and 3 replications for 8 weeks. Finally, growth indices including body weight gain, specific growth rate, feed conversion ratio and survival rate were determined. In order to determine the number of changes in color intensity and sharpness, Hue and Chroma coefficients were determined after shooting and analyzing the obtained colors using coefficients a and b with Photoshop software in the fourth and eighth weeks. The results revealed that there was no interaction between diets and ambient light, but fish raised in white light were superior in terms of all growth and survival indices (p<0.05). These results also exhibited that the effects of color sharpness (Hue) and red color index (Chroma) were greater in diets containing pigments exposed to white light.