161
© Springer International Publishing Switzerland 2016
B. Austin, D.A. Austin, Bacterial Fish Pathogens,
DOI 10.1007/978-3-319-32674-0_4
Chapter 4
Aeromonadaceae Representatives
(Motile Aeromonads)
Abstract The motile aeromonads have traditionally been linked to Aer. hydrophila,
but multiple species of fi sh pathogens have been recognized including Aer. dhakensis and Aer. schubertii. Nevertheless, Aer. hydrophila has been the focus of attention
since the start of the twenty-fi rst century particularly as a target for the development
of diagnostic and control strategies.
Keywords Septicaemia • Motile Aeromonas • Pathogenicity • Vaccines • Probiotics
The scientifi c literature abounds with references to aeromonads as fi sh pathogens,
and it is often diffi cult to distinguish the primary pathogen from opportunist or contaminant. There has been a tendency for motile aeromonads to be linked with Aer.
hydrophila and non motile representatives with Aer. salmonicida. With the advent of
more reliable taxonomic methods, the reliability of some of the earlier identifi cations may be questioned with the results that more species of fi sh pathogenic aeromonads are being recognised. Thus, there is evidence that Aer. bestiarum, Aer.
dhakensis [haemorrhagic and generalized liquefaction; Fig. 4.1 ] , Aer. sobria biovar
sobria and Aer. veronii biovar sobria may pose problems to fi sh health (Orozova
et al. 2009 ). In addition, aeromonads are often encountered in diseased fi sh, although
the proof of pathogenicity may be lacking. For example, Beaz-Hidalgo et al. 2010 ]
recovered Aer. bestiarum, Aer. hydrophila, Aer. media, Aer. piscicola, Aer. salmonicida and Aer. sobria from diseased fi sh but without demonstrating actual pathogenicity. Aer. piscicola is a newly described species from diseased fi sh, albeit without
evidence of actual pathogenicity (Beaz-Hidalgo et al. 2009 ). Jagoda et al. ( 2014 )
reported the presence of Aer. veronii (predominated) Aer. hydrophila, Aer. caviae,
Aer. jandaei, Aer. dhakensis and Aer. enteropelogenes in diseased (motile aeromonas septicaemia) freshwater ornamental fi sh in Sri Lanka. However, Aer. enteropelogenes has not been recognized before as a fi sh pathogen . Whereas the
aeromonads used to be classifi ed in Vibrionaceae, a new family was established to
accommodate them, i.e. the family Aeromonadaceae (Colwell et al. 1986 ).
© Springer International Publishing Switzerland 2016
B. Austin, D.A. Austin, Bacterial Fish Pathogens,
DOI 10.1007/978-3-319-32674-0_4
Chapter 4
Aeromonadaceae Representatives
(Motile Aeromonads)
Abstract The motile aeromonads have traditionally been linked to Aer. hydrophila,
but multiple species of fi sh pathogens have been recognized including Aer. dhakensis and Aer. schubertii. Nevertheless, Aer. hydrophila has been the focus of attention
since the start of the twenty-fi rst century particularly as a target for the development
of diagnostic and control strategies.
Keywords Septicaemia • Motile Aeromonas • Pathogenicity • Vaccines • Probiotics
The scientifi c literature abounds with references to aeromonads as fi sh pathogens,
and it is often diffi cult to distinguish the primary pathogen from opportunist or contaminant. There has been a tendency for motile aeromonads to be linked with Aer.
hydrophila and non motile representatives with Aer. salmonicida. With the advent of
more reliable taxonomic methods, the reliability of some of the earlier identifi cations may be questioned with the results that more species of fi sh pathogenic aeromonads are being recognised. Thus, there is evidence that Aer. bestiarum, Aer.
dhakensis [haemorrhagic and generalized liquefaction; Fig. 4.1 ] , Aer. sobria biovar
sobria and Aer. veronii biovar sobria may pose problems to fi sh health (Orozova
et al. 2009 ). In addition, aeromonads are often encountered in diseased fi sh, although
the proof of pathogenicity may be lacking. For example, Beaz-Hidalgo et al. 2010 ]
recovered Aer. bestiarum, Aer. hydrophila, Aer. media, Aer. piscicola, Aer. salmonicida and Aer. sobria from diseased fi sh but without demonstrating actual pathogenicity. Aer. piscicola is a newly described species from diseased fi sh, albeit without
evidence of actual pathogenicity (Beaz-Hidalgo et al. 2009 ). Jagoda et al. ( 2014 )
reported the presence of Aer. veronii (predominated) Aer. hydrophila, Aer. caviae,
Aer. jandaei, Aer. dhakensis and Aer. enteropelogenes in diseased (motile aeromonas septicaemia) freshwater ornamental fi sh in Sri Lanka. However, Aer. enteropelogenes has not been recognized before as a fi sh pathogen . Whereas the
aeromonads used to be classifi ed in Vibrionaceae, a new family was established to
accommodate them, i.e. the family Aeromonadaceae (Colwell et al. 1986 ).