494
Characteristics of the Disease
The fi sh were lethargic with surface discolouration, and evidence of fi n/tail rot,
hemorrhages on the surface, and distended abdomen, which was fi lled with transparent jelly-like material. There was infl ammation of internal organs, and visceral
hemorrhages (Abraham et al. 2016 ).
Isolation
Kidney material was inoculated onto BHIA, glutamate starch phenol red agar supplemented with 100 IU/ml penicillin G sodium salt, and Edw. ictaluri agar with
incubation at 30 +/− 2 °C for 24–48 h (Abraham et al. 2016 ).
Characteristics of the Pathogen
Pathogenicity
A culture was weakly pathogenic to African catfi sh juveniles with 35 ± 5 % mortalities resulting from challenge intraperitoneally with 1.4 × 10
7 cells/fi sh. By intramuscular injection, only 10 % mortalities resulted (Abraham et al. 2016 ). However,
Geng et al. ( 2010a ) reported 90–100 %, 65–70 %, 40–50 % and 0–5 % mortalities
after i.p. injection of channel catfi sh with doses of 1.5 × 10
6 cells/fi sh, 1.5 × 10
5 cells/
fi sh,1.5 × 10
4 cells/fi sh and 1.5 × 10
3 cells/fi sh, respectively. ECPs were harmful to
albeit to mice (Du et al. 2011 ), and may well induce apoptosis in the lymphocytes,
multiple organ failure and ultimately and death (Geng et al. 2010b ).
Box 9.10: Stenotrophomonas maltophilia
Cultures comprise Gram negative, motile, non-fermenting rods, that produce
catalase, L-proline arylamidase, and phosphatase, but not ß-galactosidase, αor ß-glucuronidase, α—glucosidase, H 2 S, indole, lysine or ornithine decarboxylase, or oxidase. Nitrates are reduced. Aesculin and blood (α-haemolysis)
but not starch or urea is attacked. Citrate is utilized. Sequencing of the 16S
rRNA gene resulted in 97–98 % homology with Stenotrophomonas maltophilia (Abraham et al. 2016 ), which is below the 99 % threshold for an acceptable identifi cation.
9 Pseudomonads
Characteristics of the Disease
The fi sh were lethargic with surface discolouration, and evidence of fi n/tail rot,
hemorrhages on the surface, and distended abdomen, which was fi lled with transparent jelly-like material. There was infl ammation of internal organs, and visceral
hemorrhages (Abraham et al. 2016 ).
Isolation
Kidney material was inoculated onto BHIA, glutamate starch phenol red agar supplemented with 100 IU/ml penicillin G sodium salt, and Edw. ictaluri agar with
incubation at 30 +/− 2 °C for 24–48 h (Abraham et al. 2016 ).
Characteristics of the Pathogen
Pathogenicity
A culture was weakly pathogenic to African catfi sh juveniles with 35 ± 5 % mortalities resulting from challenge intraperitoneally with 1.4 × 10
7 cells/fi sh. By intramuscular injection, only 10 % mortalities resulted (Abraham et al. 2016 ). However,
Geng et al. ( 2010a ) reported 90–100 %, 65–70 %, 40–50 % and 0–5 % mortalities
after i.p. injection of channel catfi sh with doses of 1.5 × 10
6 cells/fi sh, 1.5 × 10
5 cells/
fi sh,1.5 × 10
4 cells/fi sh and 1.5 × 10
3 cells/fi sh, respectively. ECPs were harmful to
albeit to mice (Du et al. 2011 ), and may well induce apoptosis in the lymphocytes,
multiple organ failure and ultimately and death (Geng et al. 2010b ).
Box 9.10: Stenotrophomonas maltophilia
Cultures comprise Gram negative, motile, non-fermenting rods, that produce
catalase, L-proline arylamidase, and phosphatase, but not ß-galactosidase, αor ß-glucuronidase, α—glucosidase, H 2 S, indole, lysine or ornithine decarboxylase, or oxidase. Nitrates are reduced. Aesculin and blood (α-haemolysis)
but not starch or urea is attacked. Citrate is utilized. Sequencing of the 16S
rRNA gene resulted in 97–98 % homology with Stenotrophomonas maltophilia (Abraham et al. 2016 ), which is below the 99 % threshold for an acceptable identifi cation.
9 Pseudomonads