Bellamya purificata mitigate the impact of Pomacea canaliculata through gut microbial changes in rice-snail co-culture system

The rice-snail coculture system represents a resource-efficient and high-yielding agroecological model. However, invasion by the exotic species <i>Pomacea canaliculata</i> disrupts its ecological equilibrium. This study examined the influences of <i>P. canaliculata</i> on the Dietary Composition and microbiota of the native snail <i>Bellamya purificata</i> under monoculture (control) and co-culture (invasion stress) conditions during 30-day and 60-day cultivation periods. Results indicate that both the cultivation condition and duration significantly modified the Dietary Composition of <i>B. purificata</i> at the genus level. At 30 days, the co-cultured <i>B. purificata</i> group exhibited no significant difference (<i>p</i> > 0.05) in gut microbial abundance compared to the mono-culture group, while demonstrating decidedly increased α-diversity and distinctly altered community structure (<i>p</i> < 0.05). The relative abundance of <i>Acinetobacter</i> was remarkably increased (<i>p</i> < 0.05), whereas multiple beneficial bacterial taxa were significantly decreased (<i>p</i> < 0.05). Functional prediction analysis revealed dramatically enhanced enrichment of neurodegenerative disease pathways (<i>p</i> < 0.05) but considerably reduced enrichment in immune disease pathways and signal molecule interaction pathways (<i>p</i> < 0.05). At 60 days, comparative analysis between <i>B. purificata</i> co-culture and mono-culture groups revealed no significant differences in gut microbial abundance, α-diversity, and community structure (<i>p</i> > 0.05). However, the relative abundances of the phyla <i>Bacteroidota</i>, <i>Actinobacteriota</i>, and <i>Planctomycetota</i> were appreciably upregulated (<i>p</i> < 0.05). Genera including <i>Aeromonas</i> and <i>Cloacibacterium</i> also exhibited notably increased relative abundances (<i>p</i> < 0.05). Conversely, the relative abundances of genera such as <i>Enterobacter</i> and <i>Enterococcus</i> were notably downregulated (<i>p</i> < 0.05). Functional prediction analysis further demonstrated greatly enhanced enrichment in cellular motility pathways and cell community-prokaryotic pathways (<i>p</i> < 0.05). These results indicate that although stress from <i>P. canaliculata</i> exerted a significant short-term negative impact on <i>B. purificata</i>, regulatory adaptations through gut microbial changes attenuated this adverse effect following prolonged exposure.