Open AccessDietary eicosapentaenoic acid requirement of juvenile rock bream, Oplegnathus fasciatus
Author(s) -
Hong J.W.,
Lee S.H.,
Moniruzzaman M.,
Park Y.,
Won S.H.,
Jo H.Y.,
Hung S.S.O.,
Bai S.C.
Publication year - 2018
Publication title -
aquaculture nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.941
H-Index - 79
eISSN - 1365-2095
pISSN - 1353-5773
DOI - 10.1111/anu.12530
Subject(s) - biology , eicosapentaenoic acid , weight gain , juvenile , zoology , lysozyme , feed conversion ratio , fish oil , fish <actinopterygii> , aquaculture , superoxide dismutase , food science , body weight , fishery , fatty acid , polyunsaturated fatty acid , biochemistry , ecology , endocrinology , enzyme
A feeding trial was conducted to evaluate the optimum dietary level of eicosapentaenoic acid ( EPA , 20:5n‐3) based on growth and non‐specific immune responses in juvenile rock bream. A basal diet without EPA supplementation was used as a control, and six other diets were prepared by supplementing with 4, 8, 12, 16, 20 or 40 g of EPA per kg diet. The actual EPA concentrations of the diets were 0.5, 4.3, 8.5, 13.0, 16.8, 21.0 and 41.2 g of EPA per kg diet, and the diets were abbreviated as EPA 0.5 , EPA 4.3 , EPA 8.5 , EPA 13.0 , EPA 16.8 , EPA 21.0 and EPA 41.2 , respectively. Triplicate groups of fish averaging 1.06 ± 0.01 g (mean ± SD ) were fed one of the seven experimental diets at the apparent satiation for 8 weeks. At the end of the feeding trial, weight gain, specific growth rate and feed efficiency of fish fed EPA 16.8 , EPA 21.0 and EPA 41.2 diets were significantly higher than those of fish fed EPA 0.5 , EPA 4.3 , EPA 8.5 and EPA 13.0 diets ( p < .05). Superoxide dismutase activity of fish fed EPA 16.8 , EPA 21.0 and EPA 41.2 diets were significantly higher than those of fish fed EPA 0.5 , EPA 4.3 and EPA 8.5 diets. Fish fed EPA 21.0 and EPA 41.2 diets showed significantly higher lysozyme activity than did fish fed EPA 0.5 , EPA 4.3 , EPA 8.5 and EPA 13.0 diets. The broken‐line analysis of weight gain indicated that the optimum dietary EPA level was 16.7 g/kg diet. These results suggested that the optimum dietary EPA level in juvenile rock bream could be greater than 16.7 g/kg diet but less than or equal to 16.8 g/kg diet based on the broken‐line analysis and the ANOVA test of weight gain.