title: Ex situ diet influences the bacterial community associated with the skin of red-eyed tree frogs (Agalychnis callidryas).
abstract: Amphibians support symbiotic bacterial communities on their skin that protect against a range of infectious pathogens, including the amphibian chytrid fungus. The conditions under which amphibians are maintained in captivity (e.g. diet, substrate, enrichment) in ex situ conservation programmes may affect the composition of the bacterial community. In addition, ex situ amphibian populations may support different bacterial communities in comparison to in situ populations of the same species. This could have implications for the suitability of populations intended for reintroduction, as well as the success of probiotic bacterial inoculations intended to provide amphibians with a bacterial community that resists invasion by the chytrid fungus. We aimed to investigate the effect of a carotenoid-enriched diet on the culturable bacterial community associated with captive red-eyed tree frogs (Agalychnis callidryas) and make comparisons to bacteria isolated from a wild population from the Chiquibul Rainforest in Belize. We successfully showed carotenoid availability influences the overall community composition, species richness and abundance of the bacterial community associated with the skin of captive frogs, with A. callidryas fed a carotenoid-enriched diet supporting a greater species richness and abundance of bacteria than those fed a carotenoid-free diet. Our results suggest that availability of carotenoids in the diet of captive frogs is likely to be beneficial for the bacterial community associated with the skin. We also found wild A. callidryas hosted more than double the number of different bacterial species than captive frogs with very little commonality between species. This suggests frogs in captivity may support a reduced and diverged bacterial community in comparison to wild populations of the same species, which could have particular relevance for ex situ conservation projects.
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: Rachael E
authors.initials: RE
authors.lastname: Antwis
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Haworth
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom ; Department of Ecological Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
authors.forename: Daniel J P
authors.initials: DJ
authors.lastname: Engelmoer
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom ; FrogLife, Peterborough, United Kingdom.
authors.forename: Victoria
authors.initials: V
authors.lastname: Ogilvy
authors.affiliation: Chester Zoo, Chester, United Kingdom.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Fidgett
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: Richard F
authors.initials: RF
authors.lastname: Preziosi
mesh_terms: D000818:Animals; D001001:Anura / Q000382:microbiology*; D001419:Bacteria / Q000254:growth & development* / Q000302:isolation & purification; D002338:Carotenoids / Q000494:pharmacology; D015169:Colony Count, Microbial; D004032:Diet; D064307:Microbiota; D010858:Pigmentation; D012867:Skin / Q000187:drug effects / Q000382:microbiology*; D013045:Species Specificity; D014197:Trees
chemical_list: D002338:Carotenoids