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Amphibians are facing population declines and extinctions, and protecting and supplementing refuges can help species survive. However, the microhabitat requirements of most species are unknown, and artificial shelters or burrows have not been well tested for amphibians. Some amphibians exhibit complex behaviour during the transition from post-reproductive dormancy to activity. However, little is known about the ecology, post-reproductive dormancy, and terrestrial activity of amphibians. Here, habitat site selection in experimental enclosures and the effects of shelters (stones, soil) and shade (with and without shade netting) on the activity, exposed body percentage, burrow depth, body-soil contact percentage, and survival of Rana dybowskii were investigated during post-reproductive dormancy and post-dormant activity. The results showed that R. dybowskii live individually under leaves, soil, stones or tree roots. Furthermore, although the dormant sites of frogs are significantly different, the distribution of male and female frogs in these sites is similar. Shading and shelter significantly affected the exposed body percentage, burrow depth and body-soil contact percentage of frogs compared with soil. In the stone group, soil and stone form the frog's refuge/burrow, whereas in the soil group, the refuge/burrow is composed entirely of soil. Even though the soil group has a deeper burrow and a larger area of soil contact with the body, it still has a higher exposure rate than the stone group. Frog activity frequency was affected by shelter and shade; the interaction of shelter and time and the interaction of shading and time were significant. The soil group had a higher activity frequency than the stone group, and the no-shade group had a higher activity frequency than the shade group. Shelter and shading differences do not significantly affect frog survival; however, the death rate during post-reproductive dormancy is lower than that during the active period. [ABSTRACT FROM AUTHOR]

Antibiotics are key in combating bacterial infections and halting disease spread, yet their effects on amphibian gut microbiomes remain poorly understood. Amphibian survival depends on their skin microbiota. Drugs used to treat amphibians may affect gut microbiota but has yet to have unexplored impacts on skin microbiota. We used Illumina sequencing to analyze the cutaneous (C) and gut (G) microbiota of healthy (H) frogs and diseased (D) frogs treated with antibiotics and evaluate their functional characteristics. The result showed that antibiotics lowered gut microbiota alpha diversity but not skin microbiota. Bray-Curtis and UniFrac measures demonstrate the significant variations in skin and gut microbiota between healthy and antibiotic-treated frogs. Bacteroidota, Firmicutes, and Proteobacteria predominated in DC and HC; Proteobacteria, Firmicutes, and Bacteroidota dominated DG and HG. Linear discriminant analysis and effect size (LEfSe) analysis identified specific bacterial taxa enriched in antibiotic-treated versus healthy frogs. Maximum likelihood (ML) analysis revealed close evolutionary relationships among certain bacterial taxa. Functional predictions indicated significant differences in metabolic pathways between groups, and BugBase analysis showed variations in bacterial phenotypes, suggesting altered microbial functions following antibiotic treatment. Antibiotic treatment in frogs significantly altered gut microbiota diversity and impacts functional pathways in both gut and skin microbiota without affecting skin microbiota alpha diversity. Antibiotics' complex effects on frog microbiota showed R. dybowskii 's delicate balance between therapeutic advantages and ecological changes, which might affect conservation and health initiatives. • New insights on antibiotics' effect on amphibian microbiota. • Antibiotics alter gut but not skin microbiota diversity. • Identified microbes linked to health and disease states. • Analyzed functional changes in microbiota post-antibiotics. [ABSTRACT FROM AUTHOR]

Climate change and human activities escalate the frequency and intensity of wildfires, threatening amphibian habitats and survival; yet, research on these impacts remains limited. Wildfire ash alters water quality, introduces contaminants, and may disrupt microbial communities, impacting gut and skin microbiota; however, the effects on gut and skin microbiota remain unclear. Rana dybowskii were exposed to five concentrations (0 g L-1, 1.25 g L-1, 2.5 g L-1, 5 g L-1, and 10 g L-1) of aqueous extracts of wildfire ashes (AEAs) for 30 days to assess AEAs' metal content, survival, and microbiota diversity via Illumina sequencing. Our results showed that the major elements in ash were Ca > K > Mg > Al > Fe > Na > Mn, while in AEA they were K > Ca > Na > Mg > As > Al > Cu. A significant decrease in amphibian survival rates with increased AEA concentration was shown. The beta diversity analysis revealed distinct shifts in microbiota composition. Notably, bacterial genera associated with potential health risks showed increased abundance in skin microbiota, emphasising the potential for ash exposure to affect amphibian health. Functional prediction analyses revealed significant shifts in metabolic pathways related to health and disease, indicating that wildfire ash exposure may influence amphibian health through changes in microbial functions. This study highlights the urgent need for strategies to mitigate wildfire ash impacts on amphibians, as it significantly alters microbiota and affects their survival and health. [Display omitted] • Wildfire ash alters water quality, introducing contaminants to amphibian habitats. • R. dybowskii survival significantly declines with increased AEA concentrations. • Gut microbiota diversity changes after ash exposure, revealing resilience and vulnerability. • Skin microbiota shows robustness, with minor changes in composition after ash exposure. • Exposure influences metabolic pathways, suggesting health implications for amphibians. [ABSTRACT FROM AUTHOR]

Amphibians' gut and skin microbiota are vital for host health. Ulcers may affect the skin microbiota, with unknown impacts on the gut microbiota. Skin diseases could influence both, but research on their interrelationships is limited. The cutaneous and gut microbiota of healthy and ulcerated Rana dybowskii were analyzed with Illumina sequencing. The result showed healthy frogs showed greater alpha diversity in skin microbiota than ulcerated ones, with no gut microbiota difference. Bray-Curtis and unweighted UniFrac distances revealed distinct skin microbiotas in healthy versus ulcerated groups and significant gut microbiota differences only in Bray-Curtis. Linear discriminant analysis of effect size (LEfSe) showed that ulcerated skin groups were enriched in Proteobacteria and healthy in Actinobacteria. A variety of analyses revealed that diseased frogs, unlike healthy ones, exhibit similar skin and gut microbiota, suggesting disease impacts microbiota relationships and composition. Using the indicator method, identify key bacterial species indicating healthy or diseased status in the frog's skin and gut microbiota. There were significant differences in skin and gut microbiota functions between diseased and healthy frogs, with disease impacting bacterial community structure and physiological functions. Research on R. dybowskii indicated disease aligns the skin and gut microbiota, affecting composition and function, with distinct bacterial indicators for health and disease status. This research underscores the complex interplay between skin and gut microbiota in amphibian health, highlighting implications for disease understanding and conservation strategies. • Pioneering impact analysis of skin ulcers on gut microbiota similarity • Discovery of distinct microbiotas in healthy and ulcerated amphibians • Uncovering high skin microbiota derivation from gut in ulcerated frogs • Unique indicator method to identify genera linked to health conditions. • Revealing correlation between skin microbiota composition and physiological functions [ABSTRACT FROM AUTHOR]