125
after 4-weeks with Mycobacterium sp. The resulting RPS was 31 %. Furthermore,
attenuated Myc. marinum with impaired ability to replicate in macrophages was demonstrated to protect zebra fi sh against Myc. marinum (Cui et al. 2010 ). Overall, these
data indicate the feasibility of eliciting protection in fi sh against some of the fi sh pathogenic mycobacteria. Therefore, there is potential for the development of vaccines.
Disinfection Ethyl alcohol (50 and 70 %), 1 % benzyl-4-chlorophenol/phenylphenol and sodium chlorite (1:5:1 or 1:18:1 in the ratio of base: water:activator) were
most effective at reducing or eliminating Myc. marinum within 1 min. Sodium
hypochlorite (50,000 mg/l) was less effective, and needed 10 min contact time to
reduce bacterial numbers. Ethyl alcohol (30 %), 1:256 N -alkyl dimethyl benzyl
ammonium chloride and 1 % potassium peroxymonosulphate – NaCl were generally ineffective even after 1 h (Mainous and Smith 2005 ).
Use of Antimicrobial Compounds Some workers advocate that clinically diseased fi sh should be destroyed, by incineration or burying in quick lime, because of
the necessity for prolonged use of chemotherapeutic agents, and the potential hazard to human health (Dulin 1979 ; Van Duijn 1981 ). Other scientists have described
treatments with chloramine B or T, cycloserine, doxycycline, erythromycin, ethambutol, ethionamide, isoniazid, kanamycin, minocycline, penicillin, rifampicin,
streptomycin, sulphonamides and tetracycline. Of these, the most economical treatment is with chloramine B or T at 10 mg/l of tank water for an exposure period of
24 h, after which the water should be changed (Van Duijn 1981 ). Erythromycin,
rifampicin and streptomycin appear to be highly effective against some isolates
(Kawakami and Kusuda 1989 , 1990 ).
Nocardiaceae Representatives
Nocardia spp.
Characteristics of the Disease
It is appreciated that nocardiosis may be problematical in fresh water (Valdez and
Conroy 1963 ; Conroy 1964 ; Snieszko et al. 1964 ; Heuschmann-Brunner 1965 ;
Campbell and MacKelvie 1968 ; Ghittino and Penna 1968 ) and marine fi sh (Wood
and Ordal 1958 ), occurring in a range of fi sh species, including Atlantic salmon
(Bransden et al. 2000 ). Symptoms similar to mycobacteriosis develop in affected
fi sh. All age groups may be infected, with lesions, manifested as small white spots,
present in the dermis, muscle, gills and internal organs (Fig. 3.8 ). Noc. seriolae has
spread from its initial focal point in Japan, and has, for example, been diagnosed
among pond cultured sea bass (Lateolabrax japonicus) and three striped tigerfi sh
( Terapon jarbua ) in Taiwan, snakehead ( Ophiocephalus argus ) in China (Wang et al.
2007 , 2009 ), largemouth bass ( Micropterus salmoides ) in China (Jiang et al. 2012 )
and weakfi sh ( Cynoscion regalis ) in the USA [mostly likely N. seriolae] (Cornwell
et al. 2011 ). In Taiwan, the cumulative mortality in sea bass reached 17.5 % within a
Nocardiaceae Representatives
after 4-weeks with Mycobacterium sp. The resulting RPS was 31 %. Furthermore,
attenuated Myc. marinum with impaired ability to replicate in macrophages was demonstrated to protect zebra fi sh against Myc. marinum (Cui et al. 2010 ). Overall, these
data indicate the feasibility of eliciting protection in fi sh against some of the fi sh pathogenic mycobacteria. Therefore, there is potential for the development of vaccines.
Disinfection Ethyl alcohol (50 and 70 %), 1 % benzyl-4-chlorophenol/phenylphenol and sodium chlorite (1:5:1 or 1:18:1 in the ratio of base: water:activator) were
most effective at reducing or eliminating Myc. marinum within 1 min. Sodium
hypochlorite (50,000 mg/l) was less effective, and needed 10 min contact time to
reduce bacterial numbers. Ethyl alcohol (30 %), 1:256 N -alkyl dimethyl benzyl
ammonium chloride and 1 % potassium peroxymonosulphate – NaCl were generally ineffective even after 1 h (Mainous and Smith 2005 ).
Use of Antimicrobial Compounds Some workers advocate that clinically diseased fi sh should be destroyed, by incineration or burying in quick lime, because of
the necessity for prolonged use of chemotherapeutic agents, and the potential hazard to human health (Dulin 1979 ; Van Duijn 1981 ). Other scientists have described
treatments with chloramine B or T, cycloserine, doxycycline, erythromycin, ethambutol, ethionamide, isoniazid, kanamycin, minocycline, penicillin, rifampicin,
streptomycin, sulphonamides and tetracycline. Of these, the most economical treatment is with chloramine B or T at 10 mg/l of tank water for an exposure period of
24 h, after which the water should be changed (Van Duijn 1981 ). Erythromycin,
rifampicin and streptomycin appear to be highly effective against some isolates
(Kawakami and Kusuda 1989 , 1990 ).
Nocardiaceae Representatives
Nocardia spp.
Characteristics of the Disease
It is appreciated that nocardiosis may be problematical in fresh water (Valdez and
Conroy 1963 ; Conroy 1964 ; Snieszko et al. 1964 ; Heuschmann-Brunner 1965 ;
Campbell and MacKelvie 1968 ; Ghittino and Penna 1968 ) and marine fi sh (Wood
and Ordal 1958 ), occurring in a range of fi sh species, including Atlantic salmon
(Bransden et al. 2000 ). Symptoms similar to mycobacteriosis develop in affected
fi sh. All age groups may be infected, with lesions, manifested as small white spots,
present in the dermis, muscle, gills and internal organs (Fig. 3.8 ). Noc. seriolae has
spread from its initial focal point in Japan, and has, for example, been diagnosed
among pond cultured sea bass (Lateolabrax japonicus) and three striped tigerfi sh
( Terapon jarbua ) in Taiwan, snakehead ( Ophiocephalus argus ) in China (Wang et al.
2007 , 2009 ), largemouth bass ( Micropterus salmoides ) in China (Jiang et al. 2012 )
and weakfi sh ( Cynoscion regalis ) in the USA [mostly likely N. seriolae] (Cornwell
et al. 2011 ). In Taiwan, the cumulative mortality in sea bass reached 17.5 % within a
Nocardiaceae Representatives