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Sarangi R.K.,The GEO Group | Mohammed G.,Central Marine Fisheries Research Institute CMFRI
Indian Journal of Marine Sciences

Algal bloom has been observed using IRS-P4 (Oceansat-1) OCM data and in situ observations during September 2002 and 2003 around the Kerala coastal and shelf water off Calicut. Algal bloom features have been observed in the total radiance, remote sensing reflectance, chlorophyll and diffuse attenuation coefficient images. In situ observations indicated the dominance of dinoflagellate Noctiluca scintillensis in the 1st, 2nd and 3rd weeks of September 2002. Red colour of water was seen even upto 30-35 kilometer from coastline and this has been got reflected in OCM derived chlorophyll images with he dense algal bloom features with very high chlorophyll concentration (20-50 mg/m3). During September (8, 20, 22, 24 and 30) 2003, high dense algal bloom patches (chl>20 mg/m3) were seen around the Calicut coast in the OCM images and spreads across the Kerala coast in the shelf water up to 20-30 km from coastline. Water colour has been found even green due to toxic micro algae Hornelia marina. Water quality parameters like SST, dissolved oxygen, salinity, pH, productivity and nutrients have been correlated with the bloom phenomenon. Source

Vinoj G.,Alagappa University | Jayakumar R.,Central Marine Fisheries Research Institute CMFRI | Chen J.-C.,National Taiwan Ocean University | Withyachumnarnkul B.,Mahidol University | And 3 more authors.
Fish and Shellfish Immunology

Four strains of N-hexanoyl-L-homoserine lactone (AHL)-degrading Pseudomonas spp., named PsDAHP1, PsDAHP2, PsDAHP3, and PsDAHP4 were isolated and identified from the intestine of Fenneropenaeus indicus. PsDAHP1 showed the highest AHL-degrading activity among the four isolates. PsDAHP1 inhibited biofilm-forming exopolysaccharide and altered cell surface hydrophobicity of virulent green fluorescent protein (GFP)-tagged Vibrio parahaemolyticus DAHV2 (GFP-VpDAHV2). Oral administration of PsDAHP1 significantly reduced zebrafish mortality caused by GFP-VpDAHV2 challenge, and inhibited colonisation of GFP-VpDAHV2 in the gills and intestine of zebrafish as evidence by confocal laser scanning microscope and selective plating. Furthermore, zebrafish receiving PsDAHP1-containing feed had increased phagocytic cells of its leucocytes, increased serum activities of superoxide dismutase and lysozyme. The results suggest that Pseudomonas aeruginosa PsDAHP1 could protect zebrafish from V.parahaemolyticus infection by inhibiting biofilm formation and enhancing defence mechanisms of the fish. © 2014 Elsevier Ltd. Source

Sunith Shine S.R.,Central Marine Fisheries Research Institute CMFRI | Feroz Khan M.,Scott Christian College Autonomous | Godwin Wesley S.,Scott Christian College Autonomous
Marine Pollution Bulletin

Polonium-210 activity concentration was analysed in the whole body tissue of periwinkle Littorina undulata collected from intertidal rocky shore along Kudankulam coast. We carried out the study for a period of 12months (2011-2012) focusing on three seasons. 210Po was found non-uniformly distributed among the periwinkles depending on the allometry. The 210Po accumulation showed a significant difference between seasons (p<0.05). Smaller sized winkles registered higher activity of 210Po compared to larger ones (p<0.05). The overall activity range of 210Po varied from 13.5 to 58.9Bq/kg (wet). The activity of 210Po was also quantified in seawater and intertidal sediments to calculate the biological concentration factor (BCF) and radiation dose rate. The dose rate to the winkles was performed using ERICA Assessment Tool and it was within the prescribed limit. The intake of 210Po through periwinkles delivered an effective dose in the range of 2.2-9.6μSv/y to human beings. © 2013 Elsevier Ltd. Source

Rajakumaran P.,Alagappa University | Vaseeharan B.,Alagappa University | Jayakumar R.,Central Marine Fisheries Research Institute CMFRI | Chidambara R.,National Prawn Co
Cytology and Genetics

Understanding of accurate phylogenetic relationship among Penaeidae shrimp is important for academic and fisheries industry. The Morphometric and Randomly Amplified Polymorphic DNA (RAPD) analysis was used to make the phylogenetic relationsip among 13 Penaeidae shrimp. For morphometric analysis forty variables and total lengths of shrimp were measured for each species, and removed the effect of size variation. The size normalized values obtained was subjected to UPGMA (Unweighted Pair-Group Method with Arithmetic Mean) cluster analysis. For RAPD analysis, the four primers showed reliable differentiation between species, and used correlation coefficient between the DNA banding patterns of 13 Penaeidae species to construct UPGMA dendrogram. Phylogenetic relationship from morphometric and molecular analysis for Penaeidae species found to be congruent. We concluded that as the results from morphometry investigations concur with molecular one, phylogenetic relationship obtained for the studied Penaeidae are considered to be reliable. © 2014, Allerton Press, Inc. Source

Gopinath R.,Microbiology and Biochemistry | Paul Raj R.,Coastal Aquaculture Authority | George K.C.,Central Marine Fisheries Research Institute CMFRI | Sanil N.K.,Central Marine Fisheries Research Institute CMFRI
Aquaculture Research

Fungal contamination of shrimp feeds affects the shelf life leading to substantial economic losses. Ultrastructural changes in Penaeus monodon sub-adults fed three different doses (50, 1000 and 2000ppb) of aflatoxin B 1 (AFB 1) were studied. At the end of 4 and 8 weeks of experiment, the hepatopancreas of shrimps were observed for ultrastructural changes. The prominent ultrastructural changes in hepatopancreas of the shrimps fed 1000 and 2000ppb AFB 1 were rupture of cell membrane and microvillus border, damage and swelling of mitochondria, fragmentation of endoplasmic reticulum, nuclear vacuolation, chromatin condensation and autophagy. This study helps to decipher the ultrastructural changes and relate the effects on biochemical, pathological, immunological and histological architecture of the shrimps fed AFB 1-incorporated feed. The observed ultrastructural changes could serve as indicators in shrimps exposed to toxicants. © 2011 Blackwell Publishing Ltd. Source

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