Central Institute of Brackishwater Aquaculture and 75

Chennai, India

Central Institute of Brackishwater Aquaculture and 75

Chennai, India
SEARCH FILTERS
Time filter
Source Type

Sandhya S.V.,Central Marine Fisheries Research Institute | Preetha K.,Central Marine Fisheries Research Institute | Nair A.V.,Central Marine Fisheries Research Institute | Antony M.L.,Central Institute of Brackishwater Aquaculture and 75 | Vijayan K.K.,Central Institute of Brackishwater Aquaculture and 75
Aquatic Microbial Ecology | Year: 2017

Cultivated microalgae are an essential source of nutrition to several farmed finfish, shellfish and many other commercially significant aquaculture species. Knowledge of microalgae-associated microhabitat is important for the development of a successful, pathogen-free hatchery rearing system. Therefore, an attempt was made to isolate (1), characterise (2) and determine the phylogenetic diversity of (3) bacteria associated with cultured microalgae, which are used as live feeds in many finfish and shellfish hatcheries. From 10 selected microalgal cultures, 34 bacterial isolates were obtained with total bacterial counts of 101 to 105 CFU ml-1. Most notably, we checked the presence of Vibrio spp., the major aquaculture pathogen in all tested microalgae and their absence suggests the suitability of these microalgae for use in aquaculture systems. Phylogenetic analysis based on 16S rDNA sequencing revealed that the bacterial phylotypes associated with these microalgae were affiliated to Gammaproteobacteria, Alphaproteobacteria and Flavobacteriia classes. The genus Marinobacter (47%) was found to be the most predominant cultivable bacterium followed by Alteromonas, Labrenzia, Oceanicaulis, Ponticoccus, Stappia and Rheinheimera. Bacteria belonging to the genera Gaetbulibacter and Maritalea were also detected and, to the best of our knowledge, this is the first report of association of these bacterial groups with microalgae. The biochemical, enzymatic and antibacterial characteristics and tolerance to various abiotic stress factors of these bacterial isolates are also described in the present paper. Altogether, the present study gives an insight into the phycosphere of cultivated microalgae, which can be further explored for improving the productivity and reliability of indoor and outdoor microalgal culture systems. © Inter-Research 2017.


Ng T.F.F.,University of South Florida | Ng T.F.F.,Blood Systems Research Institute | Alavandi S.,Central Institute of Brackishwater Aquaculture and 75 | Varsani A.,University of Canterbury | And 3 more authors.
Diseases of Aquatic Organisms | Year: 2013

Fisheries and aquaculture are impacted sporadically by newly emerged viral diseases. In most cases, searches for a causative pathogen only occur after a serious disease has emerged. As random shotgun sequencing (metagenomics) offers opportunities to identify novel viruses preemptively, the method was tested on nucleic acids extracted from the hepatopancreas of 12 healthy northern pink shrimp Farfantepenaeus duorarum captured from the Gulf of Mexico. Among the sequences, a nodavirus (Farfantepenaeus duorarum nodavirus, FdNV) and a virus with similarities to circoviruses and cycloviruses that possess circular single-stranded DNA (ssDNA) genomes, were identified. The FdNV genome sequence was most closely related phylogenetically to nodaviruses causing white tail disease in Macrobrachium rosenbergii and muscle necrosis disease in Litopenaeus vannamei. While the circular ssDNA virus represents the third to be detected in association with a marine invertebrate, transmission trials are needed to confirm its infectivity for F. duorarum. This study highlights the potential for using metagenomic approaches in fisheries and aquaculture industries to identify new potential pathogens in asymptomatic marine invertebrates, uncharacterized pathogens causing a new disease, or multiple pathogens associated with disease syndromes. © Inter-Research 2013.

Loading Central Institute of Brackishwater Aquaculture and 75 collaborators
Loading Central Institute of Brackishwater Aquaculture and 75 collaborators