Probiotic Applications in Crustaceans - Aquaculture Nutrition: Gut Health, Probiotics and Prebiotics - page 293

11.2 MAIN MICROORGANISMS EVALUATED AND USED AS
PROBIOTICS IN CRUSTACEAN AQUACULTURE
The probiotic bacteria used in aquaculture are from many phylogenetic lineages; however,
most of the probiotics studied belong to two bacterial divisions, the Firmicutes (e.g. Bacillus
spp., Lactobacillus spp., Lactococcus spp., Carnobacterium spp. etc.) and the Gammapro-
teobacteria (e.g. Vibrio spp., Pseudomonas spp., Shewanella spp. etc.), while yeasts remain
rarely studied (Gatesoupe 2007). In the case of crustaceans, the diversity of microorganisms
assessed as probiotics is important. The range of microorganisms examined has encompassed
Gram-positive bacteria ( Bacillus spp., Micrococcus sp., Lactobacillus spp., Lactococcus spp.,
Pediococcus sp. and Arthrobacter sp.), Gram-negative bacteria ( Vibrio spp., Pseudomonas
spp., Bdellovibrio spp., Aeromonas spp., Pseudomonas spp., Halomonas sp. and Alteromonas
spp.), yeasts ( Saccharomyces spp., Phaffia sp.) and microalgae ( Tetraselmis sp.).
The main probiotic bacteria documented and used in crustacean farming belong to the
Bacillus genus (Moriarty 1998; Rengpipat et al. 1998; 2000; 2003; 2008; Vaseeharan and
Ramasamy 2003; Ziaei-Nejad et al. 2006; Decamp et al. 2008; Boonthai et al. 2011). Other
Gram-positive bacteria such as Lactobacillus spp. (Villamil et al. 2003; Venkat et al. 2004;
Chiu et al. 2007; Viera et al. 2008), Lactococcus lactis (Harzevili et al. 1998), Pediococcus
acidilactici (Castex et al. 2008; 2010), Micrococcus sp. (Antony et al. 2011) and Arthrobacter
sp. (Li et al. 2006; 2008; Pai et al. 2010) have received some attention and are used in some
commercial products (Nimrat and Vuthiphandchai 2011). Autochthonous Gram-negative bac-
teria strains such as Vibrio spp. (Garriques and Arevalo 1995; Moriarty 1998; Verschuere etal.
2000a; Alavandi etal. 2004; Rodríguez etal. 2007; Krupesha Sharma etal. 2010), Bdellovibrio
spp. (Qi et al. 2009), Aeromonas sp. (Verschuere et al. 2000b), Pseudomonas spp. (Chythanya
et al. 2002; Alavandi et al. 2004; Vijayan et al. 2006; Hai et al. 2007; 2009; Pai et al. 2010),
Halomonas sp. (Zhang etal. 2009) and Alteromonas sp. (Abraham 2001) have also been docu-
mented and used in some parts of the world, although the development of commercial products
containing such microorganisms would be very limited. Furthermore, even though the sci-
entific literature available on the use of photosynthetic bacteria is scarce, bacteria such as
Thalassobacter utilis (Nogami et al. 1997), Rubrivivax gelatinosa , Rhodobacter capsulata ,
Rhodobacter spheroides and Phaeospirillum fulvum are extensively used in Chinese aquacul-
ture (Qi etal. 2009), probably being the earliest and most widely used probiotics in China since
the 1980s. Finally, yeast probiotic strains belonging to the species Saccharomyces cerevisiae
or marine yeasts are also considered, though results to date show that such microorganisms
can be efficient probiotics to optimize shrimp cultivation (Scholz et al. 1999; Burgents et al.
2004; Yang et al. 2011).
11.2.1 Bacillus spp.
The most well studied probiotics for crustacean applications belong to the genus Bacillus
(Farzanfar et al. 2006). Generally, Bacillus species tested in shrimp culture have been selected
according to their antimicrobial activities toward pathogenic Vibrio spp. based on in vitro
antagonism assays (Rengpipat et al. 1998; Decamp et al. 2008). Bacillus spp. are saprophytic
Gram-positive spore forming bacteria naturally present in a wide range of environmental