Requirements of lipid, vitamin E and selenium and their interactions on immune responses of grouper, Epinephelus malabaricus

• Main Authors: Yu-Hung Lin, 林鈺鴻
• Other Authors: Shi-Yen Shiau
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/70546353962198197718

博士 === 國立臺灣海洋大學 === 食品科學系 === 93 === The purpose of this study was to establish the dietary lipid, vitamin E and selenium (Se) requirements, and to elucidate their effects on the immune responses of juvenile grouper, Epinephelus malabaricus. The optimum dietary lipid requirement of grouper for maximal growth was 9%, and 4% of dietary lipid appeared to meet the minimal requirement for grouper. Dietary lipid supplementation enhanced the immune responses of grouper. Fish oil and corn oil as the lipid source and at the ratio of 1:1 supplementation in the diet improved grouper’s growth, immune responses and disease resistance. The optimum dietary vitamin E requirements of grouper were 61-68 and 104-115 mg/kg diet in 4 and 9% lipid diets, respectively. Diets with adequate vitamin E could reduce the oxidative stress and increase the immune responses of the fish. The dietary Se requirements of grouper was 0.7 mg/kg diet. Adequate dietary Se supplementation enhanced the immune responses of grouper, however, excess of Se (>= 2.70 mg/kg) inhibited the immune responses. Diets supplemented with high Se (2X adequate requirement) and low vitamin E (1/2 adequate requirement) had no affect on the growth, oxidative stress and immune responses of grouper, suggesting that Se could spare vitamin E for the fish. Likewise, increasing dietary vitamin E (2X adequate requirement) also spare Se requirement in the fish. No synergistic effects on the growth, oxidative stress and immune responses of grouper fed diet with both high level of vitamin E and Se. Grouper fed diet with high level (20 mg/kg) of dietary copper (Cu) resulted in high oxidative stress, and low growth and immune responses. The poor growth and low immune responses of grouper due to the oxidative stress caused by high Cu ingestion could be improved by high dietary Se (2X adequate requirement) supplementation.