精简式大口黑鲈循环水养殖系统设计与试验

Design and Testing of Streamlined Largemouth Bass Recirculating Aquaculture System

摘要:

为探索简洁、稳定、低成本循环水养殖系统的可行性及应用发展价值，通过优化改良进水结构、增氧模式、精简系统组成等方法，构建了一套淡水鱼循环水养殖系统，并开展了为期90 d的大口黑鲈养殖试验，验证系统各项指标。结果显示：启动阶段，以成熟滤材、初始滤材比例为2∶3的模式混合培养，生物膜18 d即可挂膜成功；养殖过程中，温度、溶解氧质量浓度、pH值均值分别为（27.60±0.30）℃、（10.25±0.23） mg/L、7.10±0.31，氨氮、亚硝酸盐氮质量浓度均值分别为（0.27±0.14） mg/L、（0.10±0.03） mg/L，硝酸盐氮质量浓度为7.41~35.89 mg/L，水体浊度为（0.25±0.01）NTU(Nephelometric turbidity units)；大口黑鲈平均质量从（61.25±3.06） g增长至（256.54±12.84） g，最大养殖密度达到42.54 kg/m3，饵料系数均值为1.16，成活率为98.85%~100%；肌肉质构特性分析发现大口黑鲈肌肉硬度适度增高、弹性增加，提升了鱼肉口感；运行成本大约为21.16元/kg，可以获得较好的经济收益。本研究有利于循环水养殖系统推广，也为淡水鱼科学研究提供了可靠的平台。

Abstract:

In order to explore the feasibility and application development value of simple, stable and low-cost recirculating water aquaculture system, a freshwater fish recirculating water aquaculture system was constructed by optimizing and improving the water intake structure, oxygenation mode and streamlining the system composition, and a 90 d largemouth bass aquaculture trial was carried out to verify the system indexes. The results showed that at the start-up stage, the biofilm could be successfully hung in 18 d with a mixed culture in the mode of 2∶3 ratio of mature filter media to initial filter media;during the culture process, the mean values of temperature, dissolved oxygen concentration and pH were (27.60±0.30)℃, (10.25±0.23) mg/L and 7.10±0.31, respectively, and the mean values of ammonia nitrogen concentration and nitrite nitrogen concentration were (0.27±0.14) mg/L and (0.10±0.03) mg/L, nitrate nitrogen concentration range was between 7.41 mg/L and 35.89 mg/L, and water turbidity was (0.25±0.01)NTU (nephelometric turbidity units);the average mass of largemouth bass was increased from (61.25±3.06) g to (256.54±12.84) g, and the maximal culture density reached 42.54 kg/m3, with a mean bait coefficient of 1.16 and a survival rate of 98.85%~100%;muscle texture characterization revealed that the muscle hardness of largemouth bass was increased moderately and elasticity was increased, which enhanced the taste of the fish;the running cost was about 21.16 yuan/kg, which could yield a good economic return. The research result was conducive to the popularization of recirculating water aquaculture system and it can provide a reliable platform for freshwater fish scientific research.