Fatty Acid Profile of Carps Fed Chlorella Oil-Based Diets

Abstract

Incorporating algae oil into diets provides balanced nutrition and improve growth compared to traditional diets. Fry (2.00 ± 0.50g) and fingerling (10.0±2.0g) of rohu and grass carp were fed on diets formulated as 0.67%, 1.33% and 2% Chlorella vulgaris (C. vulgaris) oil for two months.  In growth, significant difference was observed in final weight (FW) and feed conversion ratio (FCR) in fingerlings and fry regarding specie. Diets containing 1.33% algae oil showed the highest weight gain and the lowest FCR for both species at both stages. Rohu fingerlings exhibited higher WG and better FCR compared to grass carp fingerlings, while rohu fry showed higher weight gain and better FCR compared to grass carp fry. The increasing trend was observed among all experimental groups for moisture, protein, and fat contents showing the highest values in the group with 1.33 % of the inclusion level of C. vulgaris oil in the formulated diet. When comparing species, significant differences were found in moisture content among fingerlings, with grass carp fingerlings having higher moisture content than rohu fingerlings. In fry, no significant difference was present in moisture, protein, fat and ash content. Significant interactions were shown in moisture and protein content in fingerlings but no significant differences in interactions was observed in moisture, protein, fat and ash content in fry. The fatty acid profile of grass carp and rohu fingerlings, revealed significant differences regarding species, except for 18:2n-6 and 20:3n-6, and the ratio of n-3/n-6. The fatty acid profile analysis of grass carp and rohu fry, shown significant differences regarding species, except for fatty acids 18:2n-9, 20:1n-7, 20:3n-9, 20:4n-3, and 20:5n-3. In conclusion, replacing fish oil with algae oil up to 1.33% is recommended for the optimal growth of grass carp and rohu.