Next-generation sequencing (NGS) technologies have revolutionized our understanding of the complex role that microbial communities play in the health and disease of their associated hosts. However, few reports have investigated the diversity of symbiotic and pathogenic microbiota in marine mammals.1-3 Studies of bottlenose dolphins (Tursiops truncatus) have typically focused on the pathogenic microbes of stranded individuals,4 yet little is known about the normal microbiota of dolphins under human care and free-ranging populations.5 Because less than 1% of naturally occurring bacteria are culturable, a substantial fraction of the bacterial communities associated with these animals remains tobe described.6 Thus, the objective of this study was to characterize by NGS, the microbial diversity for bottlenose dolphins sampled during a health assessment project7 in Sarasota Bay, Florida, in 2015. Six samples were collected, including respiratory (blowhole and via blowplate), fecal, skin, gastric, and genital swabs from 14 dolphins (9 females and 5 males, including 4 mother and calf pairs); and a matching environmental water sample. Bacterial diversity and abundance were assessed by PCR amplification of a hypervariable region (V3) of the bacterial 16s rRNA gene for each sample, library construction, and NGS on an Illumina MiSeq platform. The MiSeq run generated approximately 22 million reads with fairly even coverage across samples and is currently being analyzed for trends in microbial diversity and abundance within and among individuals of the study population. The information gained from this study will provide an important look at the microbial diversity of free-ranging bottlenose dolphins and their aquatic environment.
The authors wish to thank the members of the 2015 Sarasota Bay Dolphin Health Assessment team for sample collection, the University of Florida (UF) Wildlife and Aquatic Veterinary Disease Laboratory for technical assistance, the Aquatic Animal Health Program and the Nacional Council of Science and Technology (CONACYT) in Mexico for financial assistance. Dolphin Quest, Inc., funded the sample collection in Sarasota Bay. Samples were collected under National Marine Fisheries Service Scientific Research Permit No. 15543 and Mote Marine Laboratory IACUC approval.
* Presenting author
+ Student presenter
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