Indigenous Lactic Acid Bacteria in Fish and Crustaceans - Aquaculture Nutrition: Gut Health, Probiotics and Prebiotics - page 149

Cypriniformes (Table 6.2). Hagi et al . (2004) investigated the composition of intestinal LAB
in silver carp ( Hypophthalmichthys molitrix ) in Lake Kasumigaura during different seasons.
As was observed for the common carp and deep-bodied crucian carp, the LAB levels in the GI
tract were higher during the summer (27 ∘ C) than in the winter (9.8 ∘ C). However, this differ-
ence was more subtle in the silver carp (LAB levels were log 5 CFU g −1 during the summer
and winter) compared to the common carp and deep-bodied crucian carp (LAB levels were
log 6 and log 7 CFU g −1 in the summer, respectively, and log 5 CFU g −1 in the winter). The
proportion of LAB with respect to the total culturable populations was less than 1% in silver
carp at both sampling points. The authors reported that the predominant intestinal LAB of all
carp species was Lc. lactis in the summer and Lc. raffinolactis, in the winter. Ghiasi (2011)
also reported the presence of Lc. raffinolactis, and Lc. lactis as allochthonous intestinal LAB
in silver carp as well as Lb. plantarum .
In an early study Halami et al . (1999) isolated and characterized Pediococcus sp. and P.
acidilactici from the gut of rohu ( Labeo rohita ). These bacteria were tested for antibacte-
rial production against several different pathogenic LAB, but they did not belong to the most
promising LAB tested, which were isolated from fowl and mushroom.
In a recent study Wu et al . (2012a) used a next-generation sequencing approach to investi-
gate the intestinal microbial community of grass carp ( Ctenopharyngodon idellus ). A complex
microbial community was revealed and the community was rich in cellulose-degrading bacte-
ria such as Anoxybacillus , Leuconostoc , Clostridium , Actinomyces and Citrobacter typical of
herbivorous species. In addition, 1.61%-7.65% of the communities were identified as Lacto-
bacillus spp. and 1.59% as Streptococcus spp.
The zebrafish ( Danio rerio ) model has been introduced in a wide variety of research fields
including studies to elucidate the importance of the gut microbiota in relation to health and
disease of vertebrates. Lb. fermentum , Lc . lactis subsp. cremoris , Lc . lactis subsp. lactis , Lc .
lactis , Lc . piscum , Lc . plantarum , Lc . raffinolactis, , Leu . citreum and Str. thermophilus have
been identified as constituents of the gut microbiome of zebrafish (Rawls et al . 2004; Gioac-
chini et al . 2012). Further studies have reported that a wide range of LAB species, particularly
lactobacilli, display favourable characteristics for zebrafish intestinal colonization and mucosal
adhesion (Gioacchini et al . 2012; Zhou et al . 2012).
6.13 CHANNIDAE
The snakeheads are members of the freshwater perciform fish family Channidae. Allameh
(2012) reported that Ae. viridans , Lb. delbrueckii subsp. delbrueckii and E. faecalis were com-
mon in the stomach and intestine of snakehead juveniles ( Channa striatus Bloch 1793) while
strains belonging to Lb . fermentum and Leu . mesenteroides subsp. mesenteroides were detected
in the stomach and intestine of adult fish. Antagonistic activities tested against A . hydrophila ,
Pseudomonas aeruginosa and Shewanella putrefaciens indicated that E. faecalis , Lb . fermen-
tum and Leu . mesenteroides subsp. mesenteroides displayed highest in vitro inhibition against
the pathogenic bacteria (Allameh 2012; Allameh et al . 2012). More recently, Allameh et al .
(2013) isolated Lb . fermentum from the stomach of snakeheads.