Effect of Different Diets on Body Biochemical Composition of the Four‐sided Sea Cucumber, Isostichopus badionotus, Under Culture Conditions

The successful development of intensive farming of sea cucumbers requires diets tailored to their needs; hence, the objective of this study was to test different commercial diets and measure their effects on the growth and biochemical composition of four‐sided sea cucumber, Isostichopus badionotus. Three diets were used: diet A (37.66% protein and 7.27% lipids), diet B (20.09% protein and 3.34% lipids), and diet C (14.83% protein and 2.45% lipids). No differences in weight gain among treatments were observed; however, sea cucumbers fed diet C presented lower carcass protein levels. Lipid content decreased in all treatments compared to the initial values. I. badionotus maintained its initial body profile regardless of the fatty acids composition of the diets; however, the body level of saturated fatty acids increased significantly in animals fed diets B and C. The concentration of polyunsaturated fatty acids was very low in all diets; nevertheless, the sea cucumbers maintained their corporal levels of C20:2, C20:3n‐3, C20:4n‐6, C20:5n‐3, and C22:6n‐3. They are also capable of elongate and desaturate 16C and 18C fatty acids supplied in the diet. These results suggest that I. badionotus is capable of maintaining its biochemical composition when fed diets containing at least 20% protein and low levels of lipids.