Sex, health and habitat alter the community composition and assembly processes of symbiotic bacteria in captive frogs

Abstract

Abstract Background Frogs are critical economic animals essential to agricultural ecosystem equilibrium. Frog symbiotic microbes possess functions like elemental cycling and immune regulation, but little is known about how frog sex and health impact gut microbes. The relationship between frog habitat and soil microbes is unclear. We aimed to determine how frog sex, health and habitat influence symbiotic microbes and community assembly. To provide guidance for sustainable frog farming and conservation. We studied gut contents and symbiotic soils of frogs from a farm with Meningitis-like infectious diseases (MID). Results We used 16S rRNA sequencing to analyze gut microbes among frog sex and health. We also compared symbiotic microbes in frog aggregation soils, native soils, and soybean soils on the farm. Frog sex and health strongly impacted gut microbe β-diversity and taxonomy. Healthy frogs had better gut microbial metabolism. Symbiotic network analysis showed healthy female frogs were more complex than males, but diseased males were more complex than females. Male frog gut microbe assembly was primarily deterministic, but female assembly was stochastic. Stochastic dispersal limitation predominated gut microbe assembly in frogs of different health. Deterministic processes most strongly influenced soybean soil symbionts. Pathogens, nitrogen respiration/fixation were enriched in soybean soil. Sulfur respiration and hydrocarbon degradation were highest in aggregation soil. Conclusion Frog gut symbionts showed major differences in network structure and assembly based on sex and health. Disease reduced gut symbiont metabolic function. Diverse symbiotic soils, especially soybean soils, could benefit frog farming. Our findings provide insight into the negative impacts of disease and other factors on frog symbiotic microbes. This could aid development of sustainable frog farming practices.