Abstract

The growth of cyanobacteria (blue-green algae) is a typical phenomenon in water bodies worldwide. The use of silver carp (Hypophthalmichthys molitrix) to reduce excessive phytoplankton development is controversial. In the case of cyanobacteria, many of which are toxic, understanding their possible digestion mechanism by fish is particularly desirable. A unique methodical approach, which consists of applying intestinal contents or extracts to a cyanobacteria culture, was used. Unicellular cyanobacteria (Cyanothece) were incubated in vitro with bile, contents of different parts of the intestinal tract, and cytosolic and microsomal extracts of the intestinal tissue of silver carp. The abundance of cyanobacteria decreased in all treatments containing either exclusively bile or its combination with intestinal contents. This research provides the first evidence of non-mechanical digestion of cyanobacteria by silver carp. Cyanobacteria incubated with intestinal contents or extracts reached mostly higher abundances than those incubated with the nutrient medium. The existence of non-mechanical digestion mediated via intestinal contents and extracts or its compensation connected with organic substance uptake is discussed.

中文翻译：

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鱼（Hypophthalmichthys molitrix）可以非机械方式消化蓝细菌

摘要

蓝细菌（蓝藻）的生长是全世界水体中的典型现象。使用of鱼（Hypophthalmichthys molitrix）来减少浮游植物过度生长是有争议的。对于其中许多是有毒的蓝细菌而言，特别需要了解它们可能被鱼消化的机制。使用了一种独特的方法方法，该方法包括将肠内容物或提取物应用于蓝细菌培养物。单细胞蓝细菌（蓝藻）与胆汁，肠道不同部位的内容物以及silver鱼肠道组织的胞质和微粒体提取物进行体外温育。在仅含有胆汁或其与肠内容物结合的所有处理中，蓝细菌的丰度都降低了。这项研究提供了silver鱼非机械消化蓝细菌的第一个证据。与肠内物质或提取物一起培养的蓝细菌比与营养培养基一起培养的细菌多得多。讨论了通过肠内容物和提取物介导的非机械消化的存在或与有机物吸收有关的补偿。