循环水养殖模式对凡纳滨对虾养殖水质及生长性能的影响

Effects of recirculating aquaculture model on water quality and growth performance of Litopenaeus vannamei

试验以平均体质量(2.39±0.20)g凡纳滨对虾为放养对象,设置循环水养殖组(RAG)和传统工厂化养殖组(IAG),每组3个重复;放养密度为750尾/m 3,盐度18;养殖期为2022年7月23日至9月10日,为期50 d。通过分析循环水养殖模式下的凡纳滨对虾(Litopenaeus vannamei)生长性能及其水质指标差异,探究循环水养殖模式在养殖生产上的可行性。结果显示,RAG平均水温显著高于IAG(P<0.05),溶解氧浓度较IAG高2.45%;养殖期RAG氨氮极显著低于IAG(P<0.01),系统成熟稳定(12 d)后亚硝态氮较IAG低24.29%;RAG虽成活率较IAG低2.17%,但收获个体质量、单位水体产量、特定生长率、增重率均高于IAG;RAG的摄食率和饵料系数低于IAG,但未表现出显著性差异(P>0.05),各组的特定生长率与几何平均体质量均表现出显著的负相关关系(P<0.05)。综合表明,循环水养殖模式可有效控制关键水质因子指标并使其处于较低水平,对节约水资源及保护环境具有重要作用。此外,在养殖生产实践中,循环水养殖模式对凡纳滨对虾的生长及产量提高也具有一定的促进作用,具备较强的可行性。

By analyzing the growth performance and water quality index differences of Litopenaeus vannamei under the recirculating aquaculture mode,the feasibility of the recirculating aquaculture mode in the aquaculture production was explored.The initial body mass of L.vannamei was(2.39±0.20)g.In this study,a recirculating aquaculture group(RAG)and a traditional industrial aquaculture group(IAG)were set up,with 3 replicates in each group.750 individuals of L.vannamei were stocked per cubic meter,and the salinity of the cultured water was 18.The aquaculture period was from July 23 to September 10,2022,lasting for 50 days.The results showed that the average water temperature of RAG was significantly higher than that of IAG(P<0.05),and the dissolved oxygen was 2.45%higher than that of IAG.The ammonia nitrogen of RAG was significantly lower than that of IAG during the culture period(P<0.01),and the nitrite nitrogen was 24.29%lower than that of IAG after the system matured and stabilized(12 days).Although the survival rate of RAG was 2.17%lower than that of IAG,but the final body mass,unit yield,specific growth rate and weight gain rate were all higher than those of IAG.The feeding rate and feed conversion rate of RAG were lower than those of IAG,but did not show significant difference(P>0.05),and the specific growth rate and geometric mean mass of each group showed a significant negative correlation(P<0.05).The comprehensive results showed that the recirculating aquaculture mode could effectively control the key water quality factor indicators at a low level,which played an important role in water resource conservation and environmental protection.In addition,in the practice of aquaculture production,the growth and production of L.vannamei could also be promoted to a certain extent,and this model had strong feasibility.