Effects of dietary astaxanthin enrichment on enhancing the colour and growth of red tilapia, Oreochromis sp.

Abstract

The aim of this research was to examine the effects of dietary inclusion of astaxanthin from Haematococcus pluvialis in commercial fish feed on the colour and growth of red tilapia, Oreochromis sp.. A 6-week feeding trial was conducted at concentration of astaxanthin at 0% (T1), 4% (T2), 8% (T3) and 12% (T4) in feed formulation to examine the growth performance, colour pigmentation on skin, texture analysis and carotenoid contents. Results showed an increment of certain growth parameter in fish fed with astaxanthin enriched diet. Increased in weight gain (WG), protein efficiency ratio (PER) was obtained in fish fed with astaxanthin enriched compared with control. All treatments with astaxanthin-enriched provided higher redness (a*) to skin than negative control that directly influence the colour of the fish. It can be concluded that inclusion of astaxanthin from green algae into commercial fish feed can be used as an alternative natural carotenoid source in Oreochromis sp. diets to ensure good pigmentation, hence improving the skin colour for more appealing and subsequently increase the market value of the fish.