凡纳滨对虾(Litopenaeus vannamei)育种核心群体在连续排污养殖模式下的生长和存活性能分析

Growth and Survival of the Litopenaeus vannamei Nucleus Selection Population in the Continuous Wastewater Discharge Mode

中文关键词: 凡纳滨对虾  连续排污  氨氮  亚硝酸盐  微生物  生长存活

英文关键词: Litopenaeus vannamei  Wastewater continuous discharge  Ammonia  Nitrite  Microorganism  Growth and survival

中文摘要:

      利用配置连续排污系统的室外水泥池养殖凡纳滨对虾(Litopenaeus vannamei) 2012级育种核心群家系，监测、分析3个生长阶段养殖环境的水质变化、育种群体的生长和存活性能，为建立安全、高效的育种核心群体养殖模式提供基础数据。结果显示，在较高养殖密度(180 ind/m2)条件下，氨氮含量在7 d内从0达到1.80 mg/L的高峰值，在随后的养殖过程中呈波浪式变化，波动范围为0.50−1.80 mg/L；亚硝酸盐含量维持在低于0.60 mg/L的水平；pH值在7.2−8.2之间；溶藻弧菌、副溶血弧菌和哈维氏弧菌的含量分别为500−6200、0−400和0−10 CFU/ml；凡纳滨对虾的平均生长速率为0.199 g/d，养殖成活率达到89.7%；凡纳滨对虾体质量的生长符合Boltzmann和Logistic模型，体质量观测值与模型拟合值的决定系数(R2)分别为0.978和0.980，预测体质量规格为10−12 g时，为其体质量增长拐点。

英文摘要:

      In this study the nucleus families of Litopenaeus vannamei produced in 2012 were reared in the outdoor concrete tanks with continuous wastewater discharge. To establish a safe and efficient culture mode for the nucleus selection population, we analyzed their growth and survival at three growth stages in five concrete tanks with certain water qualities. Electric PVC butterfly valves installed in the center of the ponds were used to manage the timed water discharge. The shrimp were fed with commercial diets 4 times daily, and the wastewater was discharged 2 hours after the feeding. The concentrations of ammonia nitrogen and microorganism were monitored on daily and weekly basis respectively. The experiment lasted for 92 days. At every stage two ponds were in use except for the first one, which ended up dividing into two ponds. The shrimp were transferred into new ponds with freshwaters, and the survival rate was determined before entering into the next stage. Data collection, graphing, and the analysis of the growth model were done with Excel 2010 and Origin 8.0. Under the high cultural density (180 ind/m2) the ammonia concentration increased to 1.80 mg/L after the first week, and ranged from 0.50 mg/L to 1.80 mg/L in the whole experimental period. The nitrite concentration maintained at a low level of 0.60 mg/L; the pH varied from 7.2 to 8.2; the range of concentrations of V. alginolyticus, V. parahaemolyticus and V. harveyi were 500−6200 CFU/ml, 0−400 CFU/ml and 0−10 CFU/ml, respectively. During the three growth stages, the average growth and survival rate for the selected population were 0.199 g/d and 89.7% respectively. The growth of the selected population could fit in the Boltzmann and Logistic models. The R2 values of the actual and the predicted weights were 0.978 and 0.980 respectively. These results suggested that the inflection point of the growth was between 10 g and 12 g. The continuous wastewater discharge mode is viable and efficient in shrimp farming because of its low ammonia nitrogen toxicity, stable pH and low pathogenicity of the microorganisms.