| 摘要: |
| 文蛤（Meretrix petechialis）是我国一种重要的海水养殖贝类，其养殖过程中病害导致的规模性死亡时有发生，已有的工作证实致病性弧菌是导致文蛤大规模死亡最为常见的病原。在本研究中，我们通过浸泡感染实验模拟了文蛤在自然条件下的弧菌胁迫环境，明确了攻毒水体中弧菌生长变化规律；攻毒过程中宿主载菌量分析显示，文蛤肝胰腺组织弧菌载量在攻毒后呈第1天急剧上升，第3天迅速下降的变化趋势，而且不同个体间载菌量差异较大；通过不同弧菌含量攻毒实验，发现在攻毒早期文蛤体内弧菌载量与水体环境的弧菌含量之间呈显著的正相关（Spearman’s ρ=0.899， P=0.000），而在感染中后期不同攻毒强度组之间无显著差异，且呈现较低水平，为0-205CFU/mg，预示着宿主免疫系统和肝胰腺微生物群落可将致病菌的数量控制在一定的范围。上述研究为开展文蛤感染发病过程中弧菌载量和免疫抗性评价相关研究提供了参考。 |
| 关键词: 文蛤 弧菌 肝胰腺 载菌量 |
| DOI： |
| 分类号:Q344 |
| 基金项目:国家自然科学(31772845)；国家贝类产业技术体系项目(No. CARS-49 ). |
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| The Vibrio load variation in the hepatopancreas of clam (Meretrix petechialis) under Vibrio parahaemolyticus challenge |
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Wang rui, Yu Jiajia, Wang Hongxia, Liu Baozhong
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Institute of Oceanology, Chinese Academy of Sciences
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| Abstract: |
| The clam Meretrix petechialis is an important cultured mollusk in China. The explosive deaths occur frequently in the main producing areas of clam culture. According to the previous research, many diseases are caused by the genus Vibrio in mollusk, which is also the main pathogenic bacteria causing mortalities of Meretrix petechialis. In present study, we defined the bacterial growth and reproduction in the seawater under Vibrio challenge during 24 hours. Then, Vibrio immersion experiments were carried out to simulate Vibrio challenge in natural environment, and we found that bacterial load in clam hepatopancreas was sharply increased in day1 and then decreased rapidly in day3 after challenge, and there were significant differences of bacterial load among different clam individuals. In the different Vibrio dose challenge experiments, a significant positive correlation was found between the bacterial load and the Vibrio dose in the seawater (Spearman’s ρ=0.899， P=0.000) in the initially phase, and no significant difference in bacterial load among different groups in the middle-late stage with a lower level of 0-205 CFU/mg. This indicates that the host immune system and the microbial community in the host hepatopancreas can control the bacteria number to a certain range. Our results provide references for the study on Vibrio load during infection and resistance evaluation in the clam M. petechialis. |
| Key words: Meretrix petechialis Vibrio hepatopancreas bacterial load |