工厂化育苗养殖体系内细菌数量动态变化研究

Study on the Quantity Dynamic Changes of Heterobacteria and Vibrios in Larvae Industrialized Culture System

[目的]探寻工厂化育苗中细菌的动态变化规律,为对虾健康养殖提供科学依据。[方法]对中国对虾育苗期养殖体系中的异养菌、弧菌、致病性副溶血弧菌进行监测。[结果]异养菌、弧菌和致病性副溶血菌数量都是对虾受精卵中高,无节幼体中最低,而后逐渐升高。在整个育苗期,对虾幼体中异养菌和养殖水体中弧菌增加1个数量级,对虾幼体中弧菌和养殖水体中异养菌均增加2个数量级。活饵中异养菌和弧菌数量很大,致病性副溶血弧菌量很低。养殖体系中幼体与水体中的异养菌和弧菌的相关系数分别为0.704和0.840;活饵中异养菌、弧菌与对虾幼体和养殖水体相关性很低或呈负相关。[结论]育苗期养殖水体与对虾幼体中细菌数量变化具有动态联系,严格控制养殖条件副溶血弧菌很难引起幼体疾病爆发,饵料中细菌数量与养殖系统中细菌数量无明显相关性。

[Objective] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [Method] The heterobacteria, vibrios and pathogenic Vibrio parahaemolyticus were monitored in larvae industrialized culture system. [Result] The heterobacteria, vibrios and pathogenic Vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nanplius, then their number would increase with grouch. During whole rearing period, both heterobacteria in larvae, vibrios in water would increase by one order of magnitude, while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude. There were many heterobacteria and vibrios but few Vibrio parahaemolyticus in living bait. The correlation coefficients between larvae and heterobacteria and vibrios in water were 0.704 and 0.840 in culture system respectively, while the correlation among heterobactefia, vibfios in living bait and larvae, water were weak or negative. [Conclusion] There was a dynamic relation between water and larvae in rearing period, and restrictly control of culture condition would restrain the occurrence of disease caused by Vibrio parahaemolyticus, besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.