[关键词]
[摘要]
通过对养殖环境灭菌, 可以降低作为对虾亲虾的饵料沙蚕携带病原弧菌的风险。本研究采用实验生态学方法, 基于病原弧菌的生物学特征, 探究不同温度灭菌处理(65 ℃处理 30 min, 100 ℃处理 30 min 和 121 ℃处理 20 min) 对沉积物的灭菌效果及加入益生菌制剂对沉积物理化指标的影响。结果表明, 各温度处理组在灭菌后立即采样, 灭菌效果良好: 65 ℃-30 min、100 ℃-30 min 和 121 ℃-20 min 处理组对沉积物中总菌落数量的灭菌率分别为 57.5%、 99.45%、99.99%, 表明随着灭菌处理温度的升高, 灭菌率逐渐提高, 对病原弧菌的灭菌率均达到 100%。对于沉积物的理化指标分析表明, 随着取样时间增长, 灭菌处理方式给沉积物–上覆水界面的氮磷扩散通量带来的影响逐渐减小, 益生菌制剂的添加能够降低水体和沉积物中的 NO3– 浓度和 PO43–浓度, 同一取样时间添加益生菌制剂处理组与未添加益生菌制剂处理组的 NO3– 扩散通量和 PO43–扩散通量有显著差异(P＜0.05)。结果表明, 65 ℃-30 min 处理即可杀灭沉积物中的全部弧菌且整个实验期间未检测到病原弧菌菌落, 添加益生菌制剂能够优化沉积物菌落结构, 抑制总菌落数量的增长, 同时对沉积物-上覆水界面的氮磷扩散通量产生影响。本研究可为沉积物灭菌及益生菌制剂在养殖环境中的应用提供数据参考。
[Key word]
[Abstract]
In the cultivation of shrimp, the use of sandworms as high quality bait often carry pathogenic Vibrio and lead to outbreaks of shrimp disease; therefore, the risk of carrying pathogenic Vibrio is expected to be reduced by sterilizing the aquaculture environment of sandworms. Based on the biological characteristics of the pathogenic Vibrio, this study was conducted to explore the sterilization effects on sediment at different temperatures (65 ℃ for 30 min, 100 ℃ for 30 min, and 121 ℃ for 20 min) and the effects of adding probiotics on the physical and chemical indexes of sediment. The results showed that the immediate sterilization results of each temperature sterilization group were good. The sterilization rate of the total colonies in the sediment was 57.5% for 65 ℃- 30 min, 99.45% for 100 ℃-30 min, and 99.99% for 121 ℃-20 min, respectively. This showed that with an increase in sterilization temperature, the sterilization rate gradually increased, and the sterilization rate for the pathogen Vibrio reached 100%. Analysis of the physicochemical indexes of the sediment showed that with the increase in sampling time, the influence of the sterilization treatment on the nitrogen-phosphorus diffusion flux at the sediment-overlying interface decreased, and the addition of probiotics could reduce the NO3– and PO43– concentrations in the water and sediment. There were significant differences in the NO3– and PO43– diffusion flux between the probiotic and non-probiotic groups at the same sampling time (P＜0.05). The study showed that all Vibrio bacteria in the sediment could be killed at 65 ℃ for 30 min, and no pathogenic Vibrio colonies were detected during the whole experiment. The addition of probiotics could optimize the sediment colony structure, inhibit the increase in total colony number, and affect the nitrogen-phosphorus diffusion flux at the sediment-overlying interface. These findings provide a reference for the application of sediment sterilization and probiotic preparation in aquaculture.
[中图分类号]
S931
[基金项目]
国家自然科学基金面上项目(42276123, 41876185)； 泰山学者工程项目； 中国水产科学研究院黄海水产研究所基本科研业务费资助项目(20603022022020)； 中国水产科学研究院基本科研业务费资助项目(2020TD50).
