Effect of different level of red cabbage (Brassica oleracea) as natural pigment on skin coloration and growth of Severum (Heros severus)

Considering the effect of dietary pigment on growth and market acceptability, this study was conducted to determine the effect of different levels of red cabbage powder on growth performance and coloration of Severum (Heros Severus). In this experiment, four levels of red cabbage powder i.e. 0, 2, 4 and 6% were added to the diet for 8 weeks. One-hundred and twenty fish with initial average weight of 10 ± 1.4 g were randomly distributed between 12 aquaria. At the end of the trial, the skin color of fish was assessed by the Lab model i.e. L* a* and b* parameters. The fish received 4% and 6% red cabbage in their diet, exhibited significant desirable color compared with the control and 2% treatments (P<0.05). The fish fed with 4% red cabbage powder, exhibited higher body weight gain (57.5 ± 7.3%), feed efficiency (88 ± 16.8%), specific growth rate (0.70 ± 0.01 %/day) and survival rate (100%) than the other treatments. The results of this experiment showed that supplementing diet with 4% red cabbage cause better pigmentation and higher growth rate in fish.