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have RTFS. These animals were anaemic, with pale gills, swollen kidney, pale liver
and elongated spleen (Austin and Stobie 1992 ).
Isolation
The pathogen was recovered from kidney swabs following incubation on BHIA,
skimmed milk agar or TSA at 25 °C for up to 7 days. Cultures comprised off-white
to yellow raised shiny colonies, which were 1–2 mm in diameter after 48 h (Austin
et al. 1988 ).
Characteristics of the Pathogen
From these traits and despite a fresh water rather than a marine origin, it was
considered that the organisms belonged in the genus Planococcus, possibly related
to P. citreus (Hao and Komagata 1985 ).
Pathogenicity
Fish, injected intraperitoneally with 10
5 cells displayed erratic swimming within
48 h. At this time, the gills were pale, the anus was protruded and abdomen was
swollen. The intestine became swollen and haemorrhagic. Slight kidney liquefaction was noted. Approximately 30–40 % of the infected fi sh died (Austin et al. 1988 ;
Austin and Stobie 1992 ).
Disease Control
Use of Antimicrobial Compounds The organism was sensitive to carbenicillin,
erythromycin, penicillin G and tetracycline, which may be effective for chemotherapy (Austin et al. 1988 ; Austin and Stobie 1992 ).
Box 3.22: Planococcus sp.
Cultures comprise motile (single polar fl agellum) often paired Gram-positive
cocci of 1–2 μm in diameter, which possess a strictly aerobic metabolism for
glucose, and produce catalase, ß-galactosidase and oxidase, but not gelatinase, H 2 S, indole or lysine decarboxylase. Growth occurs at 37 °C and in
0–15 % (w/v) sodium chloride.
Planococcaceae Representative
have RTFS. These animals were anaemic, with pale gills, swollen kidney, pale liver
and elongated spleen (Austin and Stobie 1992 ).
Isolation
The pathogen was recovered from kidney swabs following incubation on BHIA,
skimmed milk agar or TSA at 25 °C for up to 7 days. Cultures comprised off-white
to yellow raised shiny colonies, which were 1–2 mm in diameter after 48 h (Austin
et al. 1988 ).
Characteristics of the Pathogen
From these traits and despite a fresh water rather than a marine origin, it was
considered that the organisms belonged in the genus Planococcus, possibly related
to P. citreus (Hao and Komagata 1985 ).
Pathogenicity
Fish, injected intraperitoneally with 10
5 cells displayed erratic swimming within
48 h. At this time, the gills were pale, the anus was protruded and abdomen was
swollen. The intestine became swollen and haemorrhagic. Slight kidney liquefaction was noted. Approximately 30–40 % of the infected fi sh died (Austin et al. 1988 ;
Austin and Stobie 1992 ).
Disease Control
Use of Antimicrobial Compounds The organism was sensitive to carbenicillin,
erythromycin, penicillin G and tetracycline, which may be effective for chemotherapy (Austin et al. 1988 ; Austin and Stobie 1992 ).
Box 3.22: Planococcus sp.
Cultures comprise motile (single polar fl agellum) often paired Gram-positive
cocci of 1–2 μm in diameter, which possess a strictly aerobic metabolism for
glucose, and produce catalase, ß-galactosidase and oxidase, but not gelatinase, H 2 S, indole or lysine decarboxylase. Growth occurs at 37 °C and in
0–15 % (w/v) sodium chloride.
Planococcaceae Representative