Host-microbiome transplants of the schistosome snail host Biomphalaria glabrata reflect species-specific associations

Snail-borne diseases affect more than a quarter of a billion people worldwide and pose a high burden in the livestock industry. A fundamental understanding of the drivers of the epidemiology of these diseases is crucial for the development of sustainable control measures. The microbiome is increasingly being recognized as an important player in the tripartite interaction between parasitic flatworms, snail intermediate hosts and the snail microbiome. In order to better understand these interactions, transplant experiments are needed, which rely on the development of a reliable and reproducible protocol to obtain microbiome-disturbed snails. Here we report on the first successful snail microbiome transplants, which indicate that Biomphalaria glabrata can accrue novel bacterial assemblies depending on the available environmental bacteria obtained from donor snails. Moreover, the phylogenetic relatedness to the donor significantly affected the survival probability of the recipients, corroborating the phylosymbiosis pattern in freshwater snails. The transplant technique described here, complemented by field-based studies, could facilitate future research endeavors to investigate the role of specific bacteria or bacterial communities in parasitic flatworm resistance of B. glabrata and might ultimately pave the way for microbiome-mediated control of snail-borne diseases.