Skin microbiome of beluga whales: spatial, temporal, and health-related dynamics

• Published in: Animal Microbiome
• Main Authors: Amy M. Van Cise, Paul R. Wade, Caroline E. C. Goertz, Kathy Burek-Huntington, Kim M. Parsons, Tonya Clauss, Roderick C. Hobbs, Amy Apprill
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2020
• Subjects: Conservation; Health assessment; Beluga; Microbiome; 16S rRNA gene; Veterinary medicine; SF600-1100; Microbiology; QR1-502; Beluga*; Delphinapterus leucas; Alaska
• Online Access: https://doi.org/10.1186/s42523-020-00057-1; https://doaj.org/article/1558524b1eda4e519e8556365018888c

Abstract Background Host-specific microbiomes play an important role in individual health and ecology; in marine mammals, epidermal microbiomes may be a protective barrier between the host and its aqueous environment. Understanding these epidermal-associated microbial communities, and their ecological- or health-driven variability, is the first step toward developing health indices for rapid assessment of individual or population health. In Cook Inlet, Alaska, an endangered population of beluga whales (Delphinapterus leucas) numbers fewer than 300 animals and continues to decline, despite more than a decade of conservation effort. Characterizing the epidermal microbiome of this species could provide insight into the ecology and health of this endangered population and allow the development of minimally invasive health indicators based on tissue samples. Results We sequenced the hypervariable IV region of bacterial and archaeal SSU rRNA genes from epidermal tissue samples collected from endangered Cook Inlet beluga whales (n = 33) and the nearest neighboring population in Bristol Bay (n = 39) between 2012 and 2018. We examined the sequences using amplicon sequence variant (ASV)-based analyses, and no ASVs were associated with all individuals, indicating a greater degree of epidermal microbiome variability among beluga whales than in previously studied cetacean species and suggesting the absence of a species-specific core microbiome. Epidermal microbiome composition differed significantly between populations and across sampling years. Comparing the microbiomes of Bristol Bay individuals of known health status revealed 11 ASVs associated with potential pathogens that differed in abundance between healthy individuals and those with skin lesions or dermatitis. Molting and non-molting individuals also differed significantly in microbial diversity and the abundance of potential pathogen-associated ASVs, indicating the importance of molting in maintaining skin health. Conclusions We provide novel insights into the ...