Abstract: In order to investigate the effects of stocking density on the immunity, growth and water quality of Fenneropenaeus merguiensis cultured under biofloc system, Fenneropenaeus merguiensis with average body mass of (2.46±0.39) g was selected for test, stock density groups of 100 ind/m3, 300 ind/m3 and 700 ind/m3 were set, with 3 replicates in each group, and no organic carbon source was added and no water was changed during the test of 30d. The results showed that the stocking density had an effect on the immune indexes of different tissues of Fenneropenaeus merguiensis: with the increase of stocking density, in hepatopancreas,  ACP activity increased gradually, AKP activity decreased gradually, and CAT and SOD activities first increased and then decreased; in muscle, SOD and ACP activities first decreased and then increased, and CAT activity decreased gradually; there was a significant difference in the growth traits of shrimp (P<0.05), the growth of body mass and the specific growth rate of body mass decreased with the increase of density, and the survival rate also decreased; the water quality indicators also showed different trends: with the increase of density, the variation of water quality indicators increased, and the stability of water quality was poor. The study showed that under the biofloc culture mode, the stocking density significantly affected the immune-related enzyme activity, growth and water quality of Fenneropenaeus merguiensis.

Key words: Fenneropenaeus merguiensis, density, biofloc, immunity, growth, water quality

摘要： 为研究生物絮团养殖模式下养殖密度对墨吉明对虾免疫、生长和水质的影响，试验选用平均体质量为（2.46±0.39）g的墨吉明对虾，设置100尾/m3、300尾/m3、700尾/m3 3个养殖密度组，每组3个重复，试验期间不添加有机碳源、零换水，周期30 d。试验结果显示，养殖密度对墨吉明对虾不同组织的免疫指标产生影响，表现为随着养殖密度的升高，肝胰腺中，酸性磷酸酶（ACP）活力逐渐升高，碱性磷酸酶（AKP）活力逐渐降低，过氧化氢酶（CAT）和超氧化物歧化酶（SOD）活力均表现为先升高后降低；肌肉中，SOD和ACP活力呈现先降低后升高趋势，CAT活力逐渐降低；对虾生长性状存在显著差异（P<0.05），体质量增长、体质量特定增长率随着密度的增加而降低，存活率也降低；水质指标呈现出不同的变化趋势，随着密度的增加，各水质指标的变化幅度升高，水质稳定性变差。研究表明，生物絮团养殖模式下，养殖密度显著影响墨吉明对虾免疫相关酶活力、生长和水质。

关键词: 墨吉明对虾, 密度, 生物絮团, 免疫, 生长, 水质