353
Characteristics of the Pathogen
There was excellent agreement between the characteristics of the fi sh isolate and the
description of Pantoea agglomerans (Grimont and Grimont 2005a ).
There has been some debate over the precise taxonomic relationship of the
organism, which has been classifi ed as Enterobacter agglomerans , Erwinia herbicola and now as Pantoea agglomerans (see Grimont and Grimont 2005a ).
Epizootiology
The source of the pathogen was unknown (Hansen et al. 1990 ).
Disease Control
Antimicrobial Compounds
The pathogen was sensitive to ampicillin, chloramphenicol, streptomycin and tetracycline but not to novobiocin or penicillin (Hansen et al. 1990 ). Based on these data,
it would be prudent to evaluate tetracycline as a chemotherapeutant on fi sh farms, if
the disease recurs.
Box 6.9: Pantoea agglomerans
Cultures comprise pale yellow pigmented, motile, fermentative Gramnegative rods, which produce catalase and ß-galactosidase but not arginine
dihydrolase, H 2 S, indole, lysine or ornithine decarboxylase, or oxidase. The
methyl red test, Voges-Proskauer reaction, and nitrate reduction test are positive. Gelatin, but not blood, chitin or starch, is degraded. Acid is produced
from glucose, D-mannitol and sucrose. Citrate is utilised. Growth occurs at
4–37 °C but not at 40 °C, and in 0–6 % (w/v) but not 8 % (w/v) NaCl (Hansen
et al. 1990 ).
Pantoea agglomerans
Characteristics of the Pathogen
There was excellent agreement between the characteristics of the fi sh isolate and the
description of Pantoea agglomerans (Grimont and Grimont 2005a ).
There has been some debate over the precise taxonomic relationship of the
organism, which has been classifi ed as Enterobacter agglomerans , Erwinia herbicola and now as Pantoea agglomerans (see Grimont and Grimont 2005a ).
Epizootiology
The source of the pathogen was unknown (Hansen et al. 1990 ).
Disease Control
Antimicrobial Compounds
The pathogen was sensitive to ampicillin, chloramphenicol, streptomycin and tetracycline but not to novobiocin or penicillin (Hansen et al. 1990 ). Based on these data,
it would be prudent to evaluate tetracycline as a chemotherapeutant on fi sh farms, if
the disease recurs.
Box 6.9: Pantoea agglomerans
Cultures comprise pale yellow pigmented, motile, fermentative Gramnegative rods, which produce catalase and ß-galactosidase but not arginine
dihydrolase, H 2 S, indole, lysine or ornithine decarboxylase, or oxidase. The
methyl red test, Voges-Proskauer reaction, and nitrate reduction test are positive. Gelatin, but not blood, chitin or starch, is degraded. Acid is produced
from glucose, D-mannitol and sucrose. Citrate is utilised. Growth occurs at
4–37 °C but not at 40 °C, and in 0–6 % (w/v) but not 8 % (w/v) NaCl (Hansen
et al. 1990 ).
Pantoea agglomerans