Effects of Dietary Inclusion of Spirulina, Astaxanthin, Canthaxanthin or Paprika on the Skin Pigmentation of Red- and White-colored Fancy Carp Cyprinus carpio var. koi

Abstract

A feeding trial was conducted to investigate the effects of dietary carotenoid source and level on growth and skin color of red- and white-colored fancy carp Cyprinus carpio var. koi. Nine experimental diets (designated as CON, SP5, SP10, AS50, AS100, CA50, CA100, PA5 and PA10) were formulated to contain 5-10% Spirulina powder, 5-10% paprika powder, 50-100 ppm astaxanthin and 50-100 ppm canthaxanthin. The CON diet without supplementation of carotenoid source was considered as the control diet. Each experimental diet was fed to three replicate groups of fish (3.6 g/fish) to visual satiation three times a day for 8 weeks. Survival, growth and feed efficiency of fish were not significantly affected by dietary inclusion of carotenoid source and level (P>0.05). After 8 weeks feeding period, the values of a* , L* and b* of fish skin were significantly changed by dietary carotenoid source (P<0.05), but not carotenoid level. The a* value of fish fed the diets containing CA and PA was higher than control and SP diets (P<0.05). Based on the results of this study, it can be concluded that dietary inclusion of 50 ppm canthaxanthin or 5% paprika powder could increase the redness of red-and white-colored fancy carp fingerling.