单胞藻和破囊壶菌对卤虫幼体高密度短期营养强化条件和效果的探究OA北大核心CSTPCD

Short-term Artemia enrichment is an efficient approach for improving the desired nutritional value of live feed Artemia nauplii.To investigate the optimal enrichment conditions,newly-hatched Artemia nauplii were enriched with commercially produced dry powder of microalgae Phaeodactylum tricornutum and Isochrysis zhanjiangensis,and fugus Schizochytrium aggregatum in this study.And the n-3 HUFA enrichment with the above products was compared with two commercially important Artemia strains from Great Salt Lake,USA(GSL)and Aral Lake,Uzbekistan.Higher Artemia survival percentages(85% -90% )were obtained when Artemia nauplii were enriched with I.zhanjiangensis under the following conditions:enrichment dose(0.05,0.1,0.15 and 0.2 g/L),enrichment duration(12,18 and 24 h)and Artemia density(150,200 and 250 ind./mL).And the individual body length and total biomass of Artemia increased with prolonged duration and increased dose.Considering the Artemia size preference and easy operation in the hatchery,the optimal enrichment parameters were proposed with Artemia nauplii density of 150-200 ind./mL,enrichment dose of 0.1-0.2 g/L,and enrichment duration of 12-24 h.Fatty acid analysis showed that fatty acid profile of the enriched Artemia was closely related to the enrichment agent and Artemia strains.For GSL Artemia,P.tricornutum and I.zhanjianggensis enrichment remarkably increased the EPA contents(7.39 and 3.20 mg/g dw,respectively)in Artemia when compared with newly-hatched Artemia nauplii(1.63 mg/g dw);whilst for Aral Lake Artemia,slight increase of EPA content could be observed between the enriched-Artemia(17.59 mg/g dw and 17.26 mg/g dw,respectively)and newly-hatched Artemia nauplii(14.35 mg/g dw),showing that the enrichment effect closely linked to the original EPA content of Artemia strains.On the other hand,the DHA content in two Artemia strains did not show remarkable improvement when enriched with microalgae,but S.aggregatum enrichment remarkably improved the DHA content of Aral Lake Artemia(2.31 mg/g dw),which should be attributed by the high DHA content of S.aggregatum(115 mg/g dw).The results of this study will support development of microalgae enrichment agent and application of Artemia nutrition enrichment in hatcheries.