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A 60-d growth trial was conducted with the black tiger prawn, Penaeus monodon (ca. 0.8 g juveniles) at CIFE Rohtak Centre to evaluate the effects of salinity and Na+/K+ ratio of inland saline water on shrimp growth, survival, and osmoregulation. Three different salinities (5, 10, and 15 ppt) and five different Na+/K+ ratios (25:1, 45:1, 65:1, 85:1, and 27.9:1), for a total of 15 treatments were prepared by ionic manipulation. The medium with Na+/K+ ratio 27.9 was reconstituted seawater and was used as the reference treatment. At the end of the 60-d trial both salinity and Na+/K+ ratio significantly influenced the survival and growth of shrimp in inland saline water ( P < 0.05). Final mean individual weight, weight gain (%) (WG [%]) increased with decreasing Na+/K+ ratios. Survival rates were significantly higher ( P < 0.05) for Na+/K+ ratio 45 and 27.9 at salinities 10 and 15 ppt, respectively. Minimum growth and survival (0-24%) were observed in mediums with Na+/K+ ratio 85 at all salinities. Serum osmolality and osmoregulatory capacity were similar across all treatments at identical salinities except for sodium to potassium ratio (Na+/K+) 85. The serum sodium and potassium levels did not show any significant difference ( P > 0.05) for mediums with Na+/K+ ratio 25, 45, 65, and 27.9 at all salinities. Significantly different ( P < 0.05) serum sodium levels were observed in mediums with Na+/K+ ratio 85 at all salinities at the end of the trial. The serum potassium levels were significantly low in treatments with Na+/K+ ratio 85. There was no significant difference in the serum magnesium levels between treatments and the serum calcium levels were significantly lower for shrimp reared in the reference mediums. Results of this study confirm that P. monodon can be successfully cultured in low salinity waters with Na+/K+ ratio ranging between 25 and 45:1. [ABSTRACT FROM AUTHOR]

BACKGROUND Detection of improper labelling of raw and processed seafood is of global importance for reducing commercial fraud and enhancing food safety. Crabs are crustaceans with intricate morphological as well as genetic divergence among species and are popular as seafood in restaurants. Owing to the high number of crab species available, it can be difficult to identify those included in particular food dishes, thus increasing the chance of supersession. DNA barcoding is an advanced technology for detecting improper food labelling and has been used successfully to authenticate seafood. RESULTS This study identified 11 edible crab species from India by classical taxonomy and developed molecular barcodes with the cytochrome c oxidase I ( COI) gene. These barcodes were used as reference barcodes for detecting any improper labelling of 50 restaurant crab samples. Neighbour-joining tree analysis with COI barcodes showed distinct clusters of restaurant samples with respective reference species. The study demonstrated 100% improper labelling of restaurant samples to cover up acts of inferior crab supersession. CONCLUSION DNA barcoding successfully identified 11 edible crabs in accordance with classical taxonomy and discerned improper crab food labelling in restaurants of India. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Labeo rohita (rohu) is one of most important of Indian major carps, which is highly ranked among the important freshwater aquaculture species in the world. Heavy metals are major risk factors for aquatic health, which are biomagnified through the food chain. The present study was carried out to investigate the effect of different divalent salts of two heavy metals, such as zinc (ZnCl2, ZnSO4 and ZnNO3) and cadmium (CdCl2 and CdSO4), in an established fish cell line, RF developed from fin tissue of L. rohita. The RF cell line was used for assessment of heavy metal cytotoxicity through various endpoint assays, including maximum tolerated dose (MTD) determination, 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, neutral red (NR) uptake assay, and Coomassie brilliant blue (CBB) assay. Results revealed that these heavy metal salts were cytotoxic to the RF cell line at varied concentrations. MTD values were found to be 1.563, 3.125, 6.25, 12.5 and 25 mg/L for CdCl2, CdSO4, ZnCl2, Zn(NO3)2 and ZnSO4, respectively. The half-maximal inhibitory concentration values calculated by MTT, NR and CB assay were 53.83 ± 7.02, 58.03 ± 9.12 and 79.20 ± 15.27 for ZnSO4, 26.44 ± 7.01, 36.60 ± 7.82 and 155.6 ± 14.75 for Zn(NO3)2, 20.26 ± 17.95, 16.94 ± 7.05 and 87.54 ± 7.58 for ZnCl2, 5.166 ± 0.57, 15 ± 1 and 41.80 ± 8.38 for CdSO4 and 4.966 ± 0.56, 9.56 ± 1.73 and 20.93 ± 4.47 for CdCl2. This study establishes the RF cell line as an in vitro tool for assessment and monitoring of heavy metal concentration in the aquatic environment. [ABSTRACT FROM AUTHOR]

Ompok bimaculatus commonly called as Indian butter catfish is a commercially important food fish and distributed throughout India and Southeast Asia. Genetic differentiation of O. bimaculatus was investigated using cytochrome b (cyt b) gene of three different riverine populations. A total of 37 sequences of cyt b gene (1118 bp) were generated from O. bimaculatus. The mitochondrial DNA analysis revealed that O. bimaculatus has relatively high genetic diversity. The estimated haplotype and nucleotide diversity were 0.063 and 0.005, respectively. The analysis of molecular variance indicated 73.53% genetic variability between the populations and 26.47% genetic variation within population. The understanding of genetic differentiation of O. bimaculatus populations will play a key role in conservation and management of the important endangered fish species. [ABSTRACT FROM AUTHOR]

The fishes in this study belong to the difficult group. It is difficult to identify about more than 50 nemacheilid loach species in India, mainly due to the poor quality of the original descriptions, the lack of good reviews, and the similarity of a number of the banded species. In view of this, a morphometric and genetic study was conducted on four species that have been documented in Central Himalayan region of India. Using comparative methods, a contribution to the knowledge about the variability of four Himalayan hillstream loaches, a molted loach Acanthocobitis botia (Hamilton, 1822), Nemacheilus corica (Hamilton, 1822), a creek loach Schistura beavani (Gunther, 1868), and Schistura montana (McClelland, 1838), was accomplished. Morphometric data were analyzed by univariate (CV and analysis of variance) and multivariate analyses (discriminant function analysis and cluster analysis). Based on the results of these statistical analyses, generally all four species grouped into their own species cluster with minimal overlap between two species of genus Schistura. Mitochondrial DNA cytochrome b (Cyt b) gene analysis revealed 7.7-17.6% genetic distances among the four species. Molecular phylogenetic relationship among these species and other Balitoridae species was investigated using published mitochondrial Cyt b sequences. Dendrograms obtained by the maximum likelihood and maximum parsimony method analyses exhibited the same topology. According to this topology, all the four species represented distinct species group and A. botia form the most distinct species while S. beavani and S. montana are clustered together with Nemacheilus species to form a single group. This work may build the base for the revision of taxonomic identity of fishes of the family Balitoridae. The results may further help to enhance the knowledge of the ichthyologists in understanding the fish fauna of India and assist them in planning conservation and management strategies for the propagation of these less studied small indigenous species along their natural range of distribution. [ABSTRACT FROM AUTHOR]

A fibroblastic-like cell line was established from the ornamental fish, red-line torpedo ( Puntius denisonii). The red-line torpedo fin (RTF) cell line is being maintained in Leibovitz's L-15 medium supplemented with 10% fetal bovine serum (FBS) for over 1 year at 28 °C on a continuous basis in normal atmosphere. The growth rate of RTF cells increased as the FBS proportion increased from 5% to 20% at 28 °C with optimum growth at the concentrations of 10% FBS. The morphology of RTF cell was predominantly fibroblastic like. Propagation of these cell lines was serum dependent, with a low plating efficiency (<15%). Karyotyping analysis of RTF cells at the 25th passage indicated that the modal chromosome number was 2 n=50. The cell line was cryopreserved in liquid nitrogen at −196 °C and could be recovered from storage after 6 months with good cell viability. Polymerase chain reaction amplification of a fragment of two mitochondrial genes, 16S rRNA and CO1, confirmed the identity of these cell lines with those reported from this animal species, confirming that the cell lines originated from P. denisonii. The bacterial extracellular products from Vibrio cholerae MTCC3904 and Aeromonas hydrophila were found to be toxic to RTF. The cell lines were not susceptible to viral nervous necrosis virus, a marine fish virus. [ABSTRACT FROM AUTHOR]

A DNA-based barcode identification system that is applicable to all animal species will provide a simple, universal tool for the identification of fish species. The barcode system is based on sequence diversity in subunit 1 cytochrome c oxidase ( COI) gene. Identification and characterization of fish species based on morphological characters are sometimes found to be erroneous and environmentally affected. There are no studies on the genus Ompok in India at molecular level and species identification of the Ompok is usually carried out through morphological features. A total of 106 samples from three species Ompok pabda, O. pabo and O. bimaculatus were collected from eight sampling sites of seven Indian rivers. One hundred and six sequences were generated from COI region of three Ompok species and 21 haplotypes were observed. The sequence analysis of COI gene revealed three genetically distinct Ompok species and exhibited identical phylogenetic resolution among them. The partial COI gene sequence can be used as a diagnostic molecular marker for identification and resolution of taxonomic ambiguity of Ompok species. [ABSTRACT FROM AUTHOR]

Acute toxicity of an organophosphate pesticide profenofos ( O-4-bromo-2- chlorophenyl- O-ethyl S-propyl phosphorothioate) to freshwater fish, Channa punctatus (Bloch), was studied in a static bioassay. Estimated 96-hour LC50 of profenofos was found to be 2.68 μgL−1. On the basis of the obtained LC50 values for 96-hour exposure intervals, profenofos can be rated as highly toxic to C. punctatus. Fish exposed to profenofos showed hyper excitability, discoloration, erratic swimming, and secretion of excess amounts of mucus on the body and gills with eventual exhaustion and death. [ABSTRACT FROM AUTHOR]

The article presents information on a study which investigated genetic diversity in flower shrimp Penaeus semisulcatus based on mitochondrial DNA sequences of 16S rRNA gene. It notes that knowledge of genetic diversity in the species is imperative for developing broodstock and improved strains of aquatic species. it explores the estimation of the concentration of isolated DNA. It details the amplification and DNA sequencing for the species. It discusses the complexity of the assessment of genetic diversity of P. semisulcatus for appropriate conservation and management purposes.

This article documents the addition of 268 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alburnoides bipunctatus, Chamaerops humilis, Chlidonias hybrida, Cyperus papyrus, Fusarium graminearum, Loxigilla barbadensis, Macrobrachium rosenbergii, Odontesthes bonariensis, Pelteobagrus vachelli, Posidonia oceanica, Potamotrygon motoro, Rhamdia quelen, Sarotherodon melanotheron heudelotii, Sibiraea angustata, Takifugu rubripes, Tarentola mauritanica, Trimmatostroma sp. and Wallago attu. These loci were cross-tested on the following species: Alburnoides fasciatus, Alburnoides kubanicus, Alburnoides maculatus, Alburnoides ohridanus, Alburnoides prespensis, Alburnoides rossicus, Alburnoides strymonicus, Alburnoides thessalicus, Alburnoides tzanevi, Carassius carassius, Fusarium asiaticum, Leucaspius delineatus, Loxigilla noctis dominica, Pelecus cultratus, Phoenix canariensis, Potamotrygon falkneri, Trachycarpus fortune and Vimba vimba., (© 2013 Blackwell Publishing Ltd.)