Document Type : Original Article

Authors

1 MSc. student, department of fisheries, faculty of Fisheries and the Environment, Gorgan University of agricultural sciences and natural resources, Gorgan, Iran

2 Associate professor, department of fisheries, faculty of Fisheries and the Environment, Gorgan University of agricultural sciences and natural resources, Gorgan, Iran

Abstract

The orange-red spectrum of  the skin of  electric yellow (Labidochromis caeruleus) is  one  of  the  idealistic and  necessary  schemas sought  by  aquarists  and commercial producers. In this study, the effect of live foods meal on the skin coloration of juvenile electric yellow was examined. 270 fish with an average living body weight was 0.42 ± 0.11 g, and average total length was 3.3 ± 0.35 cm. Their sex was not taken into consideration. . The  fish  were  fed  twice  in  the  morning  and  afternoon  by  3-5 percent of the biomass for 8 weeks. The six different treatments (three replicates/treatment) used in the experiment were used. Skin color was measured in below the dorsal fin of all fish. Measurements were recorded at the end of the feeding trial using a Konica Minolta Chroma Meter CR400. At the end of the trial, the carotenoid supplemented diets significantly increased the values of redness (a*), yellowness (b*), and chroma (C*), and decreased the values of lightness (L*) and hue (Hoab) on the tail, body, and head areas (p<0.05). luminosity  (L*)  and  hue (H°ab) were less in fishes fed the diets with live foods and astaxanthin than  in  fishes  fed  the  control  diet  with  no pigment sources (p<0.05). yellowness  (b*),  and  Chroma  (C*)  were  greater in fish  fed  the culex and were  less  in  fish  fed  the control diet(p<0.05). Results  show  that  live foods used in this trial  can  be  used  as  an  alternative natural  carotenoid  source  in  electric yellow  diets.

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