The Gut Microbiota of Fish - Aquaculture Nutrition: Gut Health, Probiotics and Prebiotics - page 91

Table 4.2 (continued)

Dietary factor Experimental details Observations References

Feed additives
(probiotics,
prebiotics,
immunostimulants,
antibiotics and
phytobiotics)

Probiotics: numerous
bacterial and yeast species

Numerous species Refer to the reviews of

Merrifield et al.
(2010), Dimitroglou
et al. (2011)

Prebiotics: numerous
oligosaccharides and
polysaccharides

Numerous species Refer to the reviews of

Merrifield et al.
(2010), Ringø et al.
(2010), Dimitroglou
et al. (2011)

Inclusion of Thymus vulgaris
essential oil (TVEO) in
rainbow trout diets

No statistical differences
were observed between
the gut microbial profiles
of TVEO-treated and
untreated fish

Navarrete et al. (2008)

Red tilapia fed diets with or
without alginic acid
incorporation

No significant differences in
microbial profiles

Merrifield et al. (2011a)

Red tilapia fed control diets
or diets with increasing
inclusion levels of a
commercial isoquinoline
alkaloid sanguinarine
source (Sangrovit ® )

Culturable loads not affected
but LAB levels significantly
reduced with increasing
Sangrovit ® inclusion

Rawling et al. (2009)

Common carp fed diets with
or without β -glucans

Autochthonous: reduced the
abundance of LAB,
number of OTUs, species
richness and diversity
Allochthonous: reduced the
number of OTUs and
species richness

Kühlwein et al. (2013)

Antibiotics Numerous species Refer to the review of

Romero et al. (2012)

Key: FM, fishmeal; LAB, lactic acid bacteria; SBM, soybean meal.

It has been reported that the stability of the gut microbiota may be influenced by seasonal
changes (Al-Harbi and Uddin 2004; Hagi et al. 2004). In a year-long study, Hagi et al. (2004)
described the changes of LAB composition in common carp intestine; the main finding was
the predominance of Lactococcus lactis in summer (20 ∘ C) and Lactococcus raffinolactis in
winter (10 ∘ C); the change in predominant LAB was revealed to be due to the difference in
the growth profile of the two species. Also using a culture-dependent approach, Al-Harbi and
Uddin (2004) described the seasonal variation in the intestinal microbiota of hybrid tilapia
( Oreochromisniloticus × Oreochromisaureus ). Aeromonas , Shewanella and Corynebacterium
were the most abundant species with prevalence near to 20% in summer, descending to near
to 10% in winter. Considerable numbers of Pseudomonas were observed only in winter. Other
minor components such as Photobacterium , Cellulomonas and Bacillus were present in some