Characterization of the faecal bacterial community of wild young South American (Arctocephalus australis) and Subantarctic fur seals (Arctocephalus tropicalis)

Abstract

The microbiota of wild marine mammals is poorly understood, perhaps due to the migratory habits of some species and the difficulty in obtaining samples. Using high-throughput sequencing, the present study examines the faecal bacterial community of wild young South American (Arctocephalus australis) and Subantarctic fur seals (A. tropicalis). Faecal samples from South American (n = 6) and Subantarctic fur seals (n = 4) found dead along the south coast of Brazil were collected. Sequences were assigned to taxa using the Ribosomal Database Project-Bayesian classifier. Diversity of the microbiota was assessed by categorization of sequence reads into operational taxonomic units. Results indicate that Firmicutes (88.556%-84.016%) was the predominant phylum in South American and Subantarctic fur seals. The distribution of Actinobacteria and Proteobacteria varied according to the fur seal species. Fusobacteria and Bacteroidetes represented less than 1% of the sequences. The most abundant order in both fur seals was Clostridiales (88.64% and 87.49%). Individual variable incidences were observed in the composition of family among the fur seals, though the families Lachnospiraceae, Peptostreptococcaceae, Ruminococcaceae and Coriobacteriaceae were more prevalent. This study provides insight into the faecal bacterial community of wild young South American and Subantarctic fur seals.

Patterns of the fecal microbiota in the Juan Fernández fur seal (Arctocephalus philippii)

“…Consistent with previous reports in other pinniped species, five phyla dominated the JFFS fecal microbiome: Firmicutes , Fusobacteria , Bacteroidetes , Proteobacteria , and Actinobacteria (Bik et al, 2016 ; Kim et al, 2020 ; Nelson, Rogers, & Brown, 2013 ; Numberger et al, 2016 ; Pacheco‐Sandoval et al, 2019 ; Stoffel et al, 2020 ). When comparing our results to other southern pinnipeds, different microbial patterns were found in feces from other fur seal species (Medeiros et al, 2016 ; Smith et al, 2013 ). The fecal microbiome described for both the South American ( Arctophoca australis australis ) and the sub‐Antarctic fur seals ( Arctophoca tropicalis ) is almost entirely dominated by Firmicutes (88.56% and 85.02%).…”

“…The fecal microbiome has been characterized for eight pinniped species inhabiting the southern hemisphere, including three out of the eleven members forming the subfamily Arctocephalinae (fur seals): Arctocephalus pusillus doriferus (Smith et al, 2013 ), Arctocephoca australis , and Arctophoca tropicalis (Medeiros et al, 2016 ). Also part of the Arctocephalinae subfamily is the Juan Fernandez fur seal ( Arctophoca philippii philippii ) (JFFS) which is endemic to the Juan Fernandez Archipelago, a group of islands located in the middle of the Pacific Ocean 600 km away from the Chilean continental coast (Figure 1 ).…”

Gastrointestinal Parasites and Bacteria in Free-Living South American Sea Lions (Otaria flavescens) in Chilean Comau Fjord and New Host Record of a Diphyllobothrium scoticum-Like Cestode

“…Clostridium spp., especially C. perfringens, was one of most abundant bacteria isolated in this study. Clostridiales were identified as part of microbiota of different marine mammal species before assuming that they may be involved in chitin degradation (Konagaya et al, 2006;Greig et al, 2014;Delport et al, 2016;Medeiros et al, 2016;Soverini et al, 2016). C. perfringens is also regarded as a common microorganism in marine environments (Miller et al, 2006).…”

Ecological genetics of dugongs (Dugong dugon) in Queensland

“…It is well recognised that the gut microbiome plays an important role in the maintenance of a host's health and disease status (Glad et al 2010;Nelson et al 2015;Ahasan et al 2017b). The gut microbiome is an important contributor to the digestion and utilisation of food material, aiding in the breakdown of complex food particles, fermentation of complex carbohydrates, uptake and utilisation of nutrients and vitamins, and energy harvest and storage (Lavery et al 2012;Smith et al 2013;Medeiros et al 2016;Ahasan et al 2017b).…”

“…A host's diet may influence their gut microbiota due to differences in the microbes and nutritional composition that are associated with their prey or food source (Nelson et al 2013b;Medeiros et al 2016). A significant difference in the gut microbiota between wild and captive leopard seals was identified and indicated this to be due to captive seals only being fed fish caught from one location while wild seals were able to feed on a variety of prey including fish, krill and penguins (Nelson et al 2013b).…”