Probiotic treatment restores protection against lethal fungal infection lost during amphibian captivity

Host-associated microbiomes perform many beneficial functions including resisting pathogens and training the immune system. Here, we show that amphibians developing in captivity lose substantial skin bacterial diversity, primarily due to reduced ongoing input from environmental sources. We combined studies of wild and captive amphibians with a database of over 1 000 strains that allows us to examine antifungal function of the skin microbiome. We tracked skin bacterial communities of 62 endangered boreal toads, Anaxyrus boreas, across 18 time points, four probiotic treatments, and two exposures to the lethal fungal pathogen Batrachochytrium dendrobatidis (Bd) in captivity, and compared these to 33 samples collected from wild populations at the same life stage. As the amphibians in captivity lost the Bd-inhibitory bacteria through time, the proportion of individuals exposed to Bd that became infected rose from 33% to 100% in subsequent exposures. Inoculations of the Bd-inhibitory probioti...

宿主相关微生物组（Host-associated microbiomes）发挥多种有益功能，包括抵抗病原体和训练免疫系统。本研究表明，在圈养环境中发育的两栖动物会显著丧失皮肤细菌多样性，这主要是由于来自环境来源的持续输入减少所致。我们将野生与圈养两栖动物的研究数据，与一个包含逾1000株菌株的数据库相结合，以分析皮肤微生物组的抗真菌功能。我们在圈养环境中追踪了62只濒危北方蟾蜍（Anaxyrus boreas）的皮肤细菌群落，涉及18个时间点、4种益生菌处理以及2次致命真菌病原体蛙壶菌（Batrachochytrium dendrobatidis，Bd）暴露，并将这些数据与同一生命阶段野生种群的33份样本进行了比较。随着圈养两栖动物随时间推移逐渐失去抑制Bd的细菌，暴露于Bd后感染的个体比例在后续暴露中从33%上升至100%。接种抑制Bd的益生菌……