563
Characteristics of the Pathogen
Sequencing of the 16S rRNA gene revealed 98–100 % identity with V. scophthalmi and V. ichthyoenteri . However, the dnaJ gene sequences showed a higher
homology with V. scophthalmi (Qiao et al. 2012 ).
Pathogenicity
Pathogenicity was confi rmed in challenges involving olive fl ounder, with LD 50
reported as 10
6 –10
8 CFU/g of fi sh. The symptoms included darkening of the skin,
haemorrhaging in the intestine and liver, ascites, and distended abdomen (Qiao
et al. 2012 ).
Vibrio splendidus
Characteristics of the Disease
During 1987, a disease occurred in cultured turbot in northwest Spain. During the
outbreak, there was continuous low level mortality amounting to 4 % of the total
stock. Infected fi sh contained a virus, deemed to be a reovirus, and a bacterium,
which was considered to resemble V. splendidus (Lupiani et al. 1989 ). Interestingly,
a similar organism has been recovered from diseased Atlantic salmon in Scotland
(B. Austin, unpublished data), turbot [including larval turbot in Spain; Thomson
et al. 2005 ] and sea bass in Norway (Myhr et al. 1991 ) and gilt-head sea bream in
Spain (Balebona et al. 1998 ). Diseased turbot displayed swollen abdomen and
haemorrhaging in the mouth, at the anus and base of the fi ns. The swimming behaviour was not unusual. Internally, the stomach and intestine were swollen, and fi lled
with a mucoid liquid. Haemorrhaging was apparent on the walls of the peritoneal
cavity, which also contained a reddish liquid. The liver was pale (Lupiani et al.
1989 ; Angulo et al. 1994 ).
Box 10.16: Vibrio scophthalmi
The isolates degrade aesculin and urea, and reduce nitrate, produce alkaline
phosphatase, esterase lipase, leucine arylamidase, and naphthol-AS-BIphosphohydrolase, but do not produce lysine or ornithine decarboxylase or
o -nitrophenyl-ß-galactoside. The isolates produce acid from adipate, fructose,
glucose, and maltose (Qiao et al. 2012 ).
Vibrio splendidus
Characteristics of the Pathogen
Sequencing of the 16S rRNA gene revealed 98–100 % identity with V. scophthalmi and V. ichthyoenteri . However, the dnaJ gene sequences showed a higher
homology with V. scophthalmi (Qiao et al. 2012 ).
Pathogenicity
Pathogenicity was confi rmed in challenges involving olive fl ounder, with LD 50
reported as 10
6 –10
8 CFU/g of fi sh. The symptoms included darkening of the skin,
haemorrhaging in the intestine and liver, ascites, and distended abdomen (Qiao
et al. 2012 ).
Vibrio splendidus
Characteristics of the Disease
During 1987, a disease occurred in cultured turbot in northwest Spain. During the
outbreak, there was continuous low level mortality amounting to 4 % of the total
stock. Infected fi sh contained a virus, deemed to be a reovirus, and a bacterium,
which was considered to resemble V. splendidus (Lupiani et al. 1989 ). Interestingly,
a similar organism has been recovered from diseased Atlantic salmon in Scotland
(B. Austin, unpublished data), turbot [including larval turbot in Spain; Thomson
et al. 2005 ] and sea bass in Norway (Myhr et al. 1991 ) and gilt-head sea bream in
Spain (Balebona et al. 1998 ). Diseased turbot displayed swollen abdomen and
haemorrhaging in the mouth, at the anus and base of the fi ns. The swimming behaviour was not unusual. Internally, the stomach and intestine were swollen, and fi lled
with a mucoid liquid. Haemorrhaging was apparent on the walls of the peritoneal
cavity, which also contained a reddish liquid. The liver was pale (Lupiani et al.
1989 ; Angulo et al. 1994 ).
Box 10.16: Vibrio scophthalmi
The isolates degrade aesculin and urea, and reduce nitrate, produce alkaline
phosphatase, esterase lipase, leucine arylamidase, and naphthol-AS-BIphosphohydrolase, but do not produce lysine or ornithine decarboxylase or
o -nitrophenyl-ß-galactoside. The isolates produce acid from adipate, fructose,
glucose, and maltose (Qiao et al. 2012 ).
Vibrio splendidus