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challenge (Chen et al. 2015 ). The benefi t of arginine was reinforced by Zhou et al.
( 2015 ), who fed arginine to juvenile yellow catfi sh ( Pelteobagrus fulvidraco ) and
recorded similar health benefi ts.
Linolenic Acid
Linolenic acid incorporated into feed at 1.0–2.5 % and fed to darkbarbel catfi sh
( Pelteobagrus vachelli ) for 84 days led to immunomodulation and resistance to
infection with Aer. hydrophila (Li et al. 2015 ).
N -Acylated Homoserine Lactone (AHL)
Feeding with the quorum sensing signal molecules AHL, which had lactonase activity, from Bacillus reduced the development of Aer. hydrophila infection following
feeding experiments in zebra fi sh (Cao et al. 2012 ; 2014a , b ). Furthermore, feeding
quorum quenching Bacillus QSI-1 to zebra fi sh ( Danio rerio ) led to a reduction in
the pathogenicity of Aer. hydrophila and improved survival of the fi sh after challenge (RPS = 80.8 %). Overall, there was a reduction in the accumulation of AHLs,
which did not adversely affect the growth of Aer. hydrophila in co-cultures (although
culture supernatant inhibited protease production, haemolysin activity and biofi lm
formation (Chu et al. 2014 ).
Prebiotics
A commercial prebiotic, Immunogen, was fed to common carp fi ngerlings at 1, 1.5
and 2.5 g Immungen/kg diet for 8-weeks led to to improved growth and enhanced
resistance to Aer. hydrophila (Ebrahimi et al. 2012 ).
Probiotics
Bac. pumilus fed for 14 days at 10
7 cells/g of feed controlled infection by Aer.
hydrophila (Aly et al. 2008 ). Ps. aeruginosa VSG-2 when fed at 10
7 or 10
9 CFU/g
of feed for 60 days was reported to be effected at stimulating innate immunity (lysozyme, respiratory burst, superoxide dismutase and alternative complement pathway
activities and phagocytosis) and protect rohu (Labeo rohita) against Aer. hydrophila
challenge (Giri et al. 2012 ). Lactobacillus plantarum was fed at 10
7 CFU/g of diet
to hybrid catfi sh for 45 days leading to immunostimulation (enhancement of phagocytic and lysozyme activities) and protection (0 % mortalities compared with 50 %
mortalities of the controls) against experimental challenge (Butprom et al. 2013 ).
Mixtures of live and heated-inactivated preparations containing Bacillus subtilis,
Lactococcus lactis and/or Saccharomyces cerevisiae led to immunomodulation
Aeromonas hydrophila
challenge (Chen et al. 2015 ). The benefi t of arginine was reinforced by Zhou et al.
( 2015 ), who fed arginine to juvenile yellow catfi sh ( Pelteobagrus fulvidraco ) and
recorded similar health benefi ts.
Linolenic Acid
Linolenic acid incorporated into feed at 1.0–2.5 % and fed to darkbarbel catfi sh
( Pelteobagrus vachelli ) for 84 days led to immunomodulation and resistance to
infection with Aer. hydrophila (Li et al. 2015 ).
N -Acylated Homoserine Lactone (AHL)
Feeding with the quorum sensing signal molecules AHL, which had lactonase activity, from Bacillus reduced the development of Aer. hydrophila infection following
feeding experiments in zebra fi sh (Cao et al. 2012 ; 2014a , b ). Furthermore, feeding
quorum quenching Bacillus QSI-1 to zebra fi sh ( Danio rerio ) led to a reduction in
the pathogenicity of Aer. hydrophila and improved survival of the fi sh after challenge (RPS = 80.8 %). Overall, there was a reduction in the accumulation of AHLs,
which did not adversely affect the growth of Aer. hydrophila in co-cultures (although
culture supernatant inhibited protease production, haemolysin activity and biofi lm
formation (Chu et al. 2014 ).
Prebiotics
A commercial prebiotic, Immunogen, was fed to common carp fi ngerlings at 1, 1.5
and 2.5 g Immungen/kg diet for 8-weeks led to to improved growth and enhanced
resistance to Aer. hydrophila (Ebrahimi et al. 2012 ).
Probiotics
Bac. pumilus fed for 14 days at 10
7 cells/g of feed controlled infection by Aer.
hydrophila (Aly et al. 2008 ). Ps. aeruginosa VSG-2 when fed at 10
7 or 10
9 CFU/g
of feed for 60 days was reported to be effected at stimulating innate immunity (lysozyme, respiratory burst, superoxide dismutase and alternative complement pathway
activities and phagocytosis) and protect rohu (Labeo rohita) against Aer. hydrophila
challenge (Giri et al. 2012 ). Lactobacillus plantarum was fed at 10
7 CFU/g of diet
to hybrid catfi sh for 45 days leading to immunostimulation (enhancement of phagocytic and lysozyme activities) and protection (0 % mortalities compared with 50 %
mortalities of the controls) against experimental challenge (Butprom et al. 2013 ).
Mixtures of live and heated-inactivated preparations containing Bacillus subtilis,
Lactococcus lactis and/or Saccharomyces cerevisiae led to immunomodulation
Aeromonas hydrophila