三种饵料微藻在凡纳滨对虾育苗中的饲喂效果评价

以对虾幼体存活率和水质状况为考察指标，研究了牟氏角毛藻、眼点拟微球藻和钝顶螺旋藻在凡纳滨对虾N~M1期幼体饲喂中的效果评价。结果表明，(1)牟氏角毛藻按2.5×105 cells/mL浓度每天投喂三次，幼体存活率最高，达到82.79%，幼体变态正常、活力强；(2)单独投喂或与牟氏角毛藻混合投喂的结果都证实，眼点拟微球藻均会导致幼体变态拖期、挂脏等现象，不适合作为凡纳滨对虾幼体的饵料；(3)钝顶螺旋藻可以部分替代牟氏角毛藻，混合投喂时最高幼体存活率88.23%，显著高于对照组，虾苗变态发育正常，活力好，但水质受一定影响；(4)投喂牟氏角毛藻和眼点拟微球藻能明显降低氨氮、亚硝氮和菌落数等指标，净化水质。说明在凡纳滨对虾育苗中，合理使用三种饵料微藻能提高幼体存活率和净化水质。

Feeding Effect Evaluation of Three Microalgae in the Larval Rearing of Litopenaeus vannamei

The feeding effect of three microalgae, Chaetoceros muelleri, Nannochloropsis oculata and Spirulina platensis in larval rearing of Litopenaeus vannamei was studied. Survival rate of larval prawn (N~M1) and water quality of the culture system were detected to assay the effect of microalgae. The results showed that a better survival rate was achieved as 82.79% when Chaetoceros muelleri biomass of 2.5×105 cells/mL was fed by three times per day. The larval prawn showed activated and metamorphosis regular. Nannochloropsis oculata was unsuitable for Litopenaeus vannamei larvae feeding whether fed as independent or combined with Chaetoceros muelleri, since it induced metamorphosis delay and body surface attachment. Larval prawn survival rate was improved to 88.23% when combined feeding by Spirulina platensis and Chaetoceros muelleri instant of Chaetoceros muelleri independent feeding. The larval prawn showed activated and metamorphosis regular,but the water quality was affected. Flesh Chaetoceros muelleri and Nannochloropsis oculata could reduce NH3-N, NO2-N and aerobic plate count distinctly. This research suggested that larval prawn survival rate improving and water quality optimizing could be achieved by reasonable application of these three microalgae in Litopenaeus vannamei larval rearing.