Abstract

In shrimp aquaculture, manufactured diets that include various supplements and alternative fishmeal ingredients are increasingly being used and their effect on the gastrointestinal (GI) microbiota studied. However, dietary effects on different shrimp GI samples are not known. We investigated how a high (HFM) or low (LFM) fishmeal diet affects bacterial communities from different sample types collected from Penaeus monodon gastrointestinal tract. Bacterial communities of the stomach, intestine tissue and intestine digesta were assessed using 16s rRNA gene sequencing. The feed pellets were also assessed as a potential source of bacteria in the GI tract. Results showed substantial differences in bacterial communities between the two diets as well as between the different sample types. Within the shrimp GI samples, stomach and digesta communities were most impacted by diet, while the community observed in the intestine tissue was less affected. Proteobacteria, Firmicutes and Bacteroidetes were the main phyla observed in shrimp samples, with enrichment of Bacteroidetes and Firmicutes in the LFM fed shrimp. The feed pellets were dominated by Firmicutes and were largely dissimilar to the shrimp samples. Several key taxa were shared however between the feed pellets and shrimp GI samples, particularly in the LFM fed shrimp, indicating the pellets may be a significant source of bacteria observed in shrimp GI samples. In summary, both diet and sample type influenced the bacterial communities characterised from the shrimp GI tract. Thus, it is important to consider the sample type collected from the GI tract when investigating dietary impacts on gut bacterial communities in shrimp.

Key points

• Shrimp gastrointestinal communities are influenced by diet and sample type.

• The low fishmeal diet enriched bacteria that aid in polysaccharide metabolism.

• Feed pellets can be a source of bacteria-detected gastrointestinal tract of shrimp.

中文翻译：

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样品类型和高低鱼粉饮食对斑节对虾胃肠道细菌群落的影响

摘要

在虾类水产养殖中，越来越多地使用包括各种补品和替代鱼粉成分的人造饲料，并且研究了它们对胃肠道（GI）微生物群的影响。但是，对不同虾胃肠道样品的饮食影响尚不清楚。我们调查了高（HFM）或低（LFM）鱼粉饮食如何影响来自斑节对虾的不同样品类型的细菌群落胃肠道。使用16s rRNA基因测序评估了胃，肠组织和肠消化道的细菌群落。饲料颗粒也被认为是胃肠道中潜在的细菌来源。结果显示两种饮食之间以及不同样品类型之间细菌群落的显着差异。在虾的胃肠道样本中，饮食对胃和消化器官的影响最大，而在肠组织中观察到的影响则较小。变形杆菌，硬毛虫和拟杆菌是虾样品中观察到的主要菌群，其中丰富的是拟杆菌和硬菌属。在LFM喂虾。饲料颗粒以Firmicutes为主，与虾类样品在很大程度上不同。然而，饲料颗粒和虾GI样品之间有几个关键的分类单元，特别是在LFM喂养的虾中，这表明颗粒可能是虾GI样品中观察到的重要细菌来源。总之，饮食和样本类型都影响虾胃肠道特征的细菌群落。因此，在调查饮食对虾肠道细菌群落的影响时，重要的是要考虑从胃肠道收集的样品类型。

关键点

•虾的胃肠道社区受到饮食和样本类型的影响。

•低鱼粉饮食中富含有助于多糖代谢的细菌。

•饲料颗粒可能是虾经细菌检测到的胃肠道的来源。