背景:主机,寄生虫,和微生物群相互作用,形成一个复杂的生态系统。在各种肠道寄生虫感染(例如寄生虫和蠕虫)中已经观察到微生物结构的改变。有趣的是,一些寄生虫与健康的肠道微生物群相关,与肠道优生状态有关。因此,寄生虫感染引起的细菌和代谢物的变化可能会给宿主带来好处,包括保护免受其他寄生虫和促进肠道健康。已知唯一栖息在草鱼后肠的纤毛虫,扁桃体,不会对肠粘膜造成明显损伤。迄今为止,其对肠道微生物群组成的影响尚不清楚。在这项研究中,我们研究了感染了B.ctenopharyngodoni的草鱼后肠中的微生物组成,以及感染引起的肠道内容物中代谢物的变化。
结果:由B.ctenophingodoni定植与细菌多样性的增加有关,梭菌属的相对丰度较高,肠杆菌科细菌的丰度较低。Aeromonadaceae家族和柠檬酸杆菌属在受感染的鱼类中的相对丰度显着降低。此外,感染了B.ctenopharyngodoni的草鱼后肠肌酸含量显着增加。这表明B.ctenopharyngodoni的存在可以通过改变微生物群和代谢物来改善肠道健康。
结论:我们发现,感染了B.ctenopharyngodoni的草鱼表现出健康的微生物群,细菌多样性增加。结果表明,与其他致病性低的原生生物相似,刺咽芽孢杆菌重塑了后肠微生物群的组成。在B.ctenopharyngodoni的定植和增殖过程中微生物群和代谢物的变化表明,它可能在草鱼的后肠中提供积极作用。
BACKGROUND: Hosts, parasites, and microbiota interact with each other, forming a complex ecosystem. Alterations to the microbial structure have been observed in various enteric parasitic infections (e.g. parasitic protists and helminths). Interestingly, some parasites are associated with healthy gut microbiota linked to the intestinal eubiosis state. So the changes in bacteria and metabolites induced by parasite infection may offer benefits to the host, including protection from other parasitesand promotion of intestinal health. The only ciliate known to inhabit the hindgut of grass carp,
Balantidium ctenopharyngodoni, does not cause obvious damage to the intestinal mucosa. To date, its impact on intestinal microbiota composition remains unknown. In this study, we investigated the microbial composition in the hindgut of grass carp infected with B. ctenopharyngodoni, as well as the changes of metabolites in intestinal contents resulting from infection.
RESULTS: Colonization by B. ctenopharyngodoni was associated with an increase in bacterial diversity, a higher relative abundance of Clostridium, and a lower abundance of Enterobacteriaceae. The family Aeromonadaceae and the genus Citrobacter had significantly lower relative abundance in infected fish. Additionally, grass carp infected with B. ctenopharyngodoni exhibited a significant increase in creatine content in the hindgut. This suggested that the presence of B. ctenopharyngodoni may improve intestinal health through changes in microbiota and metabolites.
CONCLUSIONS: We found that grass carp infected with B. ctenopharyngodoni exhibit a healthy microbiota with an increased bacterial diversity. The results suggested that B. ctenopharyngodoni reshaped the composition of hindgut microbiota similarly to other protists with low pathogenicity. The shifts in the microbiota and metabolites during the colonization and proliferation of B. ctenopharyngodoni indicated that it may provide positive effects in the hindgut of grass carp.