조피볼락 자치어기용 과립형 미립자 사료내 지질 요구량

Abstract

The optimal lipid requirement in the granulated microdiets was determined for larval rockfish (Sebaste schlegeli). Five granulated microdiets containing different five levels of crude lipid (CL) ranging from 11 to 23% with 3% increment, referred to as the CL11, CL14, CL17, CL20 and CL23 diets, at a constant crude protein level (52.8%) were prepared in triplicate. 9 days after parturition, 4500 larvae were distributed into 15 indoor 70 L square plastic tanks (300 per tank). As the lipid content increased in the granulated microdiets, sum of n-3 highly unsaturated fatty acid (∑n-3 HUFA) content increased. The weight gain and growth rate of the rockfish larvae fed the CL20 diet were greater than of larvae fed the all other (CL11, CL14, CL17 and CL23) diets. In addition, the weight gain and growth rate of the rockfish larvae fed the CL17 and CL23 diets were greater than of larvae fed the CL11 and CL14 diets. The total length of larval rockfish fed the CL20 diet was also longer than of rockfish fed the all other diets. The whole body lipid content of rockfish larvae increased with dietary lipid content. ∑n-3 HUFA content of the whole body of rockfish larvae increased with dietary lipid content. In conclusion, dietary lipid requirement was estimated to be 17.3% based on the weight gain (broken-line model) of the larval rockfish.