Effects of different dietary supplementation of plant carotenoids on growth, coloration and behaviour of giant gourami, Trichogaster fasciata (Bloch and Schneider, 1801)

Effects of different dietary supplements of plant carotenoid sources on growth, coloration and behavioural activities of Trichogaster fasciata were carried out. Three groups of fish were fed with petal powder of rose (Rosa chinensis), China rose (Hibiscus rosasinensis) and marigold (Tagetes erecta) separately as carotenoid source along with the same basic ingredients for 90 days. The mean final weight of marigold petal powder fed group was significantly different (p <0.05) from other groups after 90 days of the experiment. The absolute growth rate, relative growth rate, weight gain percent and specific growth rate were highest in the group of fish fed with marigold petal powder while feed conversion ratio was lowest in this group. Carotenoid content in the tissue of different groups of the fish was found to be significantly different (p <0.0001). Marigold petal powder was most effective to enhance the pigmentation and coloration in the different color zones (color of eye and opercular ocellus, jugular darkening, anal, ventral and dorsal fin color etc.) of the skin of T. fasciata. Pigmentation affected the behavioural activities of the fish where male aggression and selection of males by females was high in the group fed with marigold petal powder. No significant difference was observed in the social interactions and habitat preference.