OCCURRENCE OFPASTEURELLACEAEBACTERIA IN THE ORAL CAVITY OF SELECTED MARINE MAMMAL SPECIES

Abstract

The occurrence of bacteria belonging to Pasteurellaceae in the oral cavity of captive marine mammals was investigated using culture and subsequent geno- and phenotypic characterization and phylogenetic analyses. A total of 89 bacterial isolates from pinnipeds tentatively classified with the family Pasteurellaceae were further characterized by phylogenetic analysis of rpoB gene sequences, which showed that the isolates investigated formed five distinct groups. Four strains from California sea lions (Zalophus californianus) made up group I, which was classified with Pasteurella canis. Group II comprised four strains from harbor seals (Phoca vitulina) and grey seals (Halichoerus grypus) classified with Pasteurella stomatis. Group III consisted of 28 strains, isolated from harbor and gray seals and represented Bisgaardia genomospecies 1. Two strains from a harbor and a grey seal, group IV, were classified with Bisgaardia hudsonensis. Fifty-two strains from northern fur seals (Callorhinus ursinus), walruses (Odobenus rosmarus), and California and Steller sea lions (Eumetopias jubatus) formed group V and represented Otariodibacter oris. No Pasteurellaceae isolates were obtained from cetaceans, but Pasteurellaceae were isolated from all sampled pinnipeds. On the basis of these results, it is very likely that Pasteurellaceae bacteria represent a part of the normal oral flora in pinnipeds.

Polar bear‐adapted Ursidibacter maritimus are remarkably conserved after generations in captivity

“…In contrast, our study generated data on the evolutionary path that microorganisms may endure during the process from wild to captive of their host. Pasteurellaceae species are steadily found to exhibit a commensal lifestyle in the oral cavity of wildlife, including captive marsupials and wild and captive pinnipeds (Hansen et al, 2012, 2017; Hansen, Bertelsen, et al, 2015), reptiles such as captive turtles (Hansen et al, 2016) and wild Komodo dragons (Montgomery et al, 2002). The study in Komodo dragons is to our knowledge the only previous work comparing the oral microbiota of wild and captive animals, where Pasteurellaceae were found sporadically in the wild group only, using a culture‐based approach.…”

Novel insights into pasteurellosis in captive pinnipeds

“…While several members of the family Pasteurellaceae have been identified as part of the normal flora of healthy pinnipeds, P. multocida has been isolated from cases of septicaemia, mortality and pneumonia in pinnipeds as well as cetaceans (Dunn et al, 2001;Hansen et al, 2012;Nielsen et al, 2013). Fatal septicaemic pasteurellosis has been reported in cetaceans and pinnipeds, where the most common origin of generalized pasteurellosis in captive and wild pinnipeds is bite wounds inflicted by conspecifics (Hansen et al, 2012). Pasteurellosis in marine mammals is often presented as an acute or peracute septicaemia resulting in fatality with or without clinical symptoms (Dunn et al, 2001).…”

“…Several members of the family Pasteurellaceae including Pasteurella canis and Pasteurella stomatis have been found to be part of the normal flora of healthy pinnipeds kept in captivity (Hansen et al, 2012). In marine mammals, pasteurellosis has been reported as an acute or peracute septicemia, sometimes with no obvious clinical signs other than sudden death (Dunn et al, 2001).…”

Bisgaardia miroungae sp. nov., a new member of the family Pasteurellaceae isolated from the oral cavity of northern elephant seals (Mirounga angustirostris), and emended description of the genus Bisgaardia

“…The most frequently described species of the family Pasteurellaceae isolated from pinnipeds has been Pasteurella multocida (Dunn et al , 2001; Smith et al , 1978). However, recently, a new genus containing one species, Otariodibacter oris , was isolated from the oral cavity of healthy sea lions ( Otariinae ), fur seals ( Arctocephalinae ) and walruses ( Odobenidae ) (Hansen et al , 2012a, b). Similarly, a new genus containing one species, Bisgaardia hudsonensis , and one genomospecies, Bisgaardia genomospecies 1, has been isolated from both healthy and diseased seals ( Phocidae ) (Foster et al , 2011; Hansen et al , 2012a).…”

“…However, recently, a new genus containing one species, Otariodibacter oris , was isolated from the oral cavity of healthy sea lions ( Otariinae ), fur seals ( Arctocephalinae ) and walruses ( Odobenidae ) (Hansen et al , 2012a, b). Similarly, a new genus containing one species, Bisgaardia hudsonensis , and one genomospecies, Bisgaardia genomospecies 1, has been isolated from both healthy and diseased seals ( Phocidae ) (Foster et al , 2011; Hansen et al , 2012a). B. hudsonensis has also been isolated from an infected seal bite in a human (Sundeep & Cleeve, 2011) and both Bisgaardia genomospecies 1 and O. oris have been isolated in pure culture from abscesses in a harbour seal ( Phoca vitulina ) and California sea lions ( Zalophus californianus ), respectively (Hansen et al , 2013).…”