Indigenous Lactic Acid Bacteria in Fish and Crustaceans - Aquaculture Nutrition: Gut Health, Probiotics and Prebiotics - page 128

6 Indigenous Lactic Acid Bacteria in Fish

and Crustaceans

Daniel L. Merrifield 1 ,JoséLuisBalcázar 2 , Carly Daniels 3 ,
Zhigang Zhou 4 , Oliana Carnevali 5 , Yun-Zhang Sun 6 , Seyed
Hossein Hoseinifar 7 and Einar Ringø 8
1 School of Biological Sciences, Plymouth University, UK
2 Catalan Institute for Water Research (ICRA), University of Girona, Spain
3 The National Lobster Hatchery, Padstow, Cornwall, UK
4 Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, PR China
5 Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle
Marche, Ancona, Italy
6 Fisheries College, Jimei University, Xiamen, PR China
7 Department of Fisheries, Gorgan University of Agricultural Science and Natural
Resources, Gorgan, Iran
8 Norwegian College of Fishery Science, UiT The Arctic University of Norway,
Tromsø, Norway

ABSTRACT

The gut microbiota of fish plays an important role in mediating and stimulating host gas-
trointestinal (GI) development, aiding digestive function, maintaining mucosal tolerance,
stimulating the host immune response and providing a level of protection against gastric
infections. Lactic acid bacteria (LAB), which are generally considered as favourable bacteria
due to their abilities to antagonize bacterial pathogens, are often identified as components
of the gut microbiota of fish. Members of the Lactobacillus , Lactococcus , Leuconostoc ,
Enterococcus and Streptococcus genera have been isolated by culture-dependent methods as
minor components of the indigenous GI populations in salmonids. Carnobacterium species,
such as C. ( piscicola ) maltaromaticum , C. mobile , C. divergens , C. alterfunitum -like, C.
inhibens and Carnobacterium spp., have been thought to be the dominant/core LAB genus
in salmonids and can account for up to 15% of the viable culturable populations. Recent
culture-independent molecular analyses have led us to question whether Carnobacterium
truly are the most prevalent LAB genus in salmonids. Techniques such as denaturing gradient
gel electrophoresis (DGGE), temporal temperature gradient electrophoresis (TTGE), and
16S rRNA clone libraries confirm the presence of Carnobacterium spp. but have also
identified Lactobacillus spp., Streptococcus spp . , Lactococcus lactis , Weissella cibaria and