在实验室循环水养殖条件下,分别研究了养殖密度和饵料组成对中华绒螯蟹仔蟹阶段(仔Ⅰ—仔Ⅲ)生长、存活的影响。养殖密度实验设置D1(75只/m-2)、D2(150只/m-2)、D3(300只/m-2)和D4(450只/m-2)4个密度组。结果表明:D2组仔蟹体重最高,并在仔Ⅰ和仔Ⅱ阶段显著高于D3和D4组(P〈0.05),成活率随密度增加呈先增加后下降趋势,不同仔蟹阶段成活率以D1和D2组最高,D3组次之,D4组最低,且差异显著(P〈0.05)。另外,仔Ⅰ阶段D2和D3密度组HUFA和n-3PUFA含量显著高于D3和D4密度组(P〈0.05)。饵料组成实验中结果表明:混合投喂组仔蟹体重在所有投喂组中最高,并在仔Ⅰ和仔Ⅲ阶段显著高于配合饲料组和生物饵料组(P〈0.05)。存活率以配合饲料组最高,混合饲料组次之,生物饵料组最低,且仔Ⅱ阶段和仔Ⅲ生物饵料组成活率显著低于其余两组(P〈0.05)。此外,仔Ⅰ和仔Ⅱ阶段生物饵料组总脂含量显著低于其余两组,生物饵料组HUFA、n-3PUFA和n-6PUFA普遍低于其余两组,并在不同仔蟹阶段达到显著水平(P〈0.05)。实验结果表明养殖密度、饵料组成对中华绒螯蟹仔蟹阶段的生长、存活有显著影响,研究结果为中华绒螯蟹仔蟹培育技术的改进提供了一定的理论基础。
Effects of stocking densities and diets on growth and survival of Chinese mitten crab ( Eriocheir sinensis) during its larval stages(C1-C3) were tested under laboratory conditions. Four stocking densities D1 (75 ind/m^2),D2 (150 ind/ m^2),D3 (300 ind/m2 ) and D4 (450 ind/ m^2 ) were designed. The results showed that the body weight obtained the highest value in D2, and was signifi-cantly higher than D3 and D4 in C1 and C2 satges(P〈0. 05). Survival rate declined significantly with the increasing larval stages, and obtained the highest result in D1 and D2, followed by D3 and D4. In addition, the relative contents of HUFA and n-3PUFA in C1 stage reared with lower stocking densities D1 and D2 are significantly higher than D3 and D4 (P〈0. 05). As to dites experiment, lar-val crab fed with formula diet obtained highest body weight compared to those fed with mixed diet and live diet, especially in C1 and C3 stages(P〈0. 05). Survival rate reached the highest in F1, followed by F2 and F3 and larva crabs fed woth live diet obtained the low-est survival rate in C2 and C3 stages(P〈0. 05). The relative content of total lipid was the lowest in larval crabs fed with live diet,which was the same variation trend as HUFA, n-3PUFA and n-6PUFA(P〈0. 05). The results proved that stocking densities and diets had significant effects on growth and survival in larval stages, which may provide some basic information to improve the production of larval mitten crabs.