Culture of Azolla and its efficacy in diet of Labeo rohita

Comparative study was conducted to examine growth rate, biomass production and proximate composition of six different Azolla species. Essential amino acids (EAA) of different Azolla species in linear growth phase also analysed. A feeding trial was conducted in the cemented tanks (8.0 m × 1.25 m × 1.0 m) to examine efficacy of dried Azolla mixture as a feed ingredient in the diet of Labeo rohita. Azolla mixture was incorporated in diet at 15%, 25% and 35% level. Highest weight gain was recorded with the diet containing 25% Azolla mixture with specific growth rate of 0.7468% / day. The experimental fish recorded the value of exponent ‘b’ in the range of 2.5155 to 2.7760. The condition factor ‘K’ of all experimental fish was above 1.0 (1.2237-1.2326) indicating good condition of experimented fish. Incorporation of Azolla in the fish diets reduced the fat content in muscle of fish.