Prebiotics in Finfish: An Update - Aquaculture Nutrition: Gut Health, Probiotics and Prebiotics - page 370

( Carassius auratus auratus ), golden shiner ( Notemigonus crysoleucas ), fathead minnow
( Pimephales promelas ) and blunt snout bream ( Megalobrama amblycephala ) (Ringø et al .
2010; Table 14.3).
14.5.1 Common carp
Staykov etal . (2005) reported higher weight gain when common carp (initial ∼140 g) were fed
dietary MOS (2g kg −1 ) for 60 days. In addition the authors reported increased serum lysozyme
and complement activities of fish fed prebiotic with highest activities after 30 days of feeding.
Ebrahimi et al . (2011) investigated the effects of Immunogen (inclusion levels: 0.5, 1, 1.5 and
2.5gkg −1 ) on common carp fingerling (11.12 ± 0.55 g) growth performance, carcass compo-
sition and resistance against Aeromonas hydrophila . Although weight gain was not affected,
improved FCR and PER were observed in the 1.5 g Immunogen kg −1 treatment. Inclusion
of Immunogen at 2.5 g kg −1 significantly increased carcass protein content, haematological
parameters and plasma total protein concentration. At the end of the experiments, intestinal
samples (entire intestine including contents) were tested for total culturable bacterial counts.
The bacterial levels were significantly higher in fish fed the control diet compared to the prebi-
otic treatments, and the lowest level was recorded when fish were fed 2.5 g Immunogen kg −1 .
In the challenge test dietary Immunogen significantly elevated resistance of carp fingerling
against A. hydrophila . Mazurkiewicz et al . (2008) investigated the effect of Fermacto, a com-
mercial feed supplement based upon primary fermentation ( Aspergillus ), in common carp fry,
and observed that inclusion of 3 g Fermacto kg −1 had a positive effect on SGR, FCR and PER,
while lower inclusion levels of 1 and 2 g kg −1 did not have a similar effect. In a study with
juvenile carp, the effects of MOS (1, 2 and 3 g kg −1 ) were investigated on growth, survival,
body composition and some haematological parameters (Akrami et al . 2012a). Inclusion of
1gMOSkg −1 significantly enhanced haematocrit and lymphocyte levels, while total leukocyte
levels, erythrocyte levels, haemoglobin concentration and eosinophil levels were not signifi-
cantly affected. Furthermore, growth performance and carcass composition were improved,
but were not significantly different compared to the other treatment groups.
14.5.2 Crucian carp
Little information is available with regards to prebiotics in crucian carp and to the authors'
knowledge only three studies have been carried out (Xu etal . 2009; Zhou etal . 2009a; Liu etal .
2013). Xu et al . (2009) investigated the effects of XOS on growth performance and digestive
enzymes activity of allogynogenetic crucian carp ( Carassiusauratusgibelio ) (16.88-17.56 g).
Three levels of XOS were included in the diets; 50 mg kg −1 , 100 mg kg −1 and 200 mg kg −1 ,
respectively. The results revealed that dietary XOS inclusions significantly increased growth
performance as well as digestive enzyme (protease and amylase) activities. However survival
rate was not affected. In the study of Zhou and co-authors, fish (initial weight ∼40 g) were
fed MOS (1 and 2 g kg −1 ) in combination with Chinese traditional medicines. Consequently
growth performance and serum lysozyme and superoxide dismutase activities were increased
by dietary supplementation. Furthermore, inclusion of 2 g oligosaccharides kg −1 improved
resistance of crucian carp against A . hydrophila . In a more recent study, Liu et al . (2013)
evaluated the effect of MOS on physiological responses, HSP70 gene expression and resistance
to A . hydrophila infection in allogynogenetic crucian carp. Supplementation of MOS (240 and
480 mg kg −1 ) significantly increased serum ALP and serum globulin concentration prior to