418
Immunostimulants/Dietary Supplements An aqueous extract of Asiatic pennywort ( Centella asiatica ) has been proposed for the control of columnaris in Nile
tilapia when used as a bath at 100 mg/l for what appeared to be a continuous exposure (Rattanachaikunsopon and Phumkhachorn 2009 ). AlkoSel [inactivated
Saccharomyces cerevisiae; dosed at 0.25 g/kg of feed ] has been attributed with
immunostimulatory activity when fed to rainbow trout for 7 whereupon challenge
with Fla. columnare led to demonstrable protection (Suomalainen et al. 2009 ).
Disinfection Diquat was effective as a bath treatment for channel catfi sh, effectively stopping mortalities caused by the pathogen. Also, there was some reduction
in mortalities following bathing in chloramine-T, hydrogen peroxide and potassium
permanganate, but not so with copper sulphate and hydrogen peroxide (ThomasJinu and Goodwin 2004 ; Bowker et al. 2013 ). Experiments with rainbow trout fi ngerlings have demonstrated a potential for the use of sodium chloride baths in
reducing mortalities caused by columnaris following waterborne challenge
(Suomalainen et al. 2005 ).
Antimicrobial Compounds Farkas and Oláh ( 1980 ) suggested the use of a salt
(sodium chloride) bath for controlling infections. We agree with this suggestion,
insofar as a 30 s dip in 8 % (w/v) sodium chloride cleared up an infection in rainbow
trout fi ngerlings within a few days. Other remedies, which have met with varying
degrees of success, include:
arsenic, cadmium, copper, lead and selenium mixture, dosed at 1–3 μg/l for 1 day
(MacFarlane et al. 1986 );
copper sulphate, used at a dilution of 1:2000, for a 1–2 min dip (Snieszko 1958b );
malachite green, used at a dilution of 1:15,000, for a 1–30 s dip (Snieszko 1958b );
pyridylmercuric acetate, used at 2 mg/l for 1 h (Snieszko 1958b );
diquat, used at 1–2 mg/l for 30–60 min (McCarthy 1975 );
quaternary ammonium compounds, used at 2 mg/l for 1 h (McCarthy 1975 );
oxytetracycline, used at 50–100 mg/kg body weight of fi sh/day for 10 days (Snieszko
1964 ; Ferguson 1977 ). For external infections, oxytetracycline or chlortetracycline may also be used as a bath, i.e. 26–60 mg/l for 1 h (Snieszko and Hoffman
1963 ; Wood 1968 );
oxolinic acid, used at 10 mg/kg of body weight/day for 10 days (Soltani et al. 1995 )
chloramphenicol, used at 5–10 mg/l, has been suggested for aquarium fi sh (Snieszko
1958b );
Florfenicol dosed at10mg/kg of body weight for 10 consecutive days (Matthews
et al. 2013 ).
sulphadiazine, sulphamerazine or sulphamethiazone, used at 220 mg/kg body
weight of fi sh/day for 10 days (Snieszko 1954 ; Wolf and Snieszko 1963 ).
Sulphamerazine has been used successfully to treat rainbow trout, but not chinook salmon (Johnson and Brice 1952 ).
7 Flavobacteria and Cytophagas
Immunostimulants/Dietary Supplements An aqueous extract of Asiatic pennywort ( Centella asiatica ) has been proposed for the control of columnaris in Nile
tilapia when used as a bath at 100 mg/l for what appeared to be a continuous exposure (Rattanachaikunsopon and Phumkhachorn 2009 ). AlkoSel [inactivated
Saccharomyces cerevisiae; dosed at 0.25 g/kg of feed ] has been attributed with
immunostimulatory activity when fed to rainbow trout for 7 whereupon challenge
with Fla. columnare led to demonstrable protection (Suomalainen et al. 2009 ).
Disinfection Diquat was effective as a bath treatment for channel catfi sh, effectively stopping mortalities caused by the pathogen. Also, there was some reduction
in mortalities following bathing in chloramine-T, hydrogen peroxide and potassium
permanganate, but not so with copper sulphate and hydrogen peroxide (ThomasJinu and Goodwin 2004 ; Bowker et al. 2013 ). Experiments with rainbow trout fi ngerlings have demonstrated a potential for the use of sodium chloride baths in
reducing mortalities caused by columnaris following waterborne challenge
(Suomalainen et al. 2005 ).
Antimicrobial Compounds Farkas and Oláh ( 1980 ) suggested the use of a salt
(sodium chloride) bath for controlling infections. We agree with this suggestion,
insofar as a 30 s dip in 8 % (w/v) sodium chloride cleared up an infection in rainbow
trout fi ngerlings within a few days. Other remedies, which have met with varying
degrees of success, include:
arsenic, cadmium, copper, lead and selenium mixture, dosed at 1–3 μg/l for 1 day
(MacFarlane et al. 1986 );
copper sulphate, used at a dilution of 1:2000, for a 1–2 min dip (Snieszko 1958b );
malachite green, used at a dilution of 1:15,000, for a 1–30 s dip (Snieszko 1958b );
pyridylmercuric acetate, used at 2 mg/l for 1 h (Snieszko 1958b );
diquat, used at 1–2 mg/l for 30–60 min (McCarthy 1975 );
quaternary ammonium compounds, used at 2 mg/l for 1 h (McCarthy 1975 );
oxytetracycline, used at 50–100 mg/kg body weight of fi sh/day for 10 days (Snieszko
1964 ; Ferguson 1977 ). For external infections, oxytetracycline or chlortetracycline may also be used as a bath, i.e. 26–60 mg/l for 1 h (Snieszko and Hoffman
1963 ; Wood 1968 );
oxolinic acid, used at 10 mg/kg of body weight/day for 10 days (Soltani et al. 1995 )
chloramphenicol, used at 5–10 mg/l, has been suggested for aquarium fi sh (Snieszko
1958b );
Florfenicol dosed at10mg/kg of body weight for 10 consecutive days (Matthews
et al. 2013 ).
sulphadiazine, sulphamerazine or sulphamethiazone, used at 220 mg/kg body
weight of fi sh/day for 10 days (Snieszko 1954 ; Wolf and Snieszko 1963 ).
Sulphamerazine has been used successfully to treat rainbow trout, but not chinook salmon (Johnson and Brice 1952 ).
7 Flavobacteria and Cytophagas