Dispersal among zebrafish intestinal microbiomes

Much of what we know about the microbial communities colonizing animals has focused on interactions between individual hosts and their associated microorganisms. However, animals in nature exist within populations of interacting individuals, and these interactions have the potential to allow microorganisms to disperse and transmit among hosts. We conducted an experiment to determine whether inter-host dispersal influences the assembly of microbial communities associated with zebrafish (Danio rerio) intestines in a manner predicted by ecological metacommunity theory. To manipulate host factors and dispersal of microorganisms among hosts, wild type and immune-deficient zebrafish were raised in one of three housing treatments: cohoused with individuals of both genotypes, cohoused with only individuals of the same genotype, or solitary without exposure to other fish. We then compared the diversity and composition of intestinal communities to predictions from a computational metacommunity model to guide the interpretation of the results.