The effect of China Rose levels as natural carotenoids on the pigmentation and total carotenoids contents in the muscle of blue gourami

The effect of China Rose, a natural pigment source, was investigated on blue gourami muscle color change and carotenoid content. In this study, one control diet (without pigment) and three experimental diets containing 0.5, 1.5 and 2.5% China rose were prepared. The fish fingerlings were reared in twelve aquaria with 60×30×30 cm dimensions with stocking density of 10 fish per aquarium. The fish with average weight of 0.52 ± 0.02 g were fed in triplicate with the diets for 70 days. During the rearing period, the fish skin color was monitored using a portable colorimeter and color change factors (L*a*b*) were analyzed. Results showed that there was no marked difference among the fish fed with China Rose diets (P>0.05). However, total carotenoid content of the fish in China Rose treatments was significantly higher than that of the control group (P