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The Western Ghats, being very rich in freshwater fish diversity, has recently been confirmed as a globally significant centre of diversity and endemism for freshwater species and comprise one of the 34 global biodiversity hotspots. Owing to its extreme ichthyofaunal diversity, the present study was designed to generate cytochrome oxidase I (COI) DNA barcodes for the identification of some commonly exploited fishes from the west-flowing rivers of northern Western Ghats. Twenty-three fish specimens representing 6 families and 10 species were barcoded from the major west-flowing rivers of the northern Western Ghats. The obtained barcodes discriminated all the species with sufficient barcode gap. The average Kimura two parameter (K2P) values for within species, the genus and family distances were 0.37, 17.74 and 18.51% respectively. The neighbour-joining tree revealed distinct clusters corresponding to the taxonomic status of the species. Generated barcodes are expected to provide the much-needed baseline reference for the ichthyofaunal biodiversity of the global biodiversity hotspot. [ABSTRACT FROM AUTHOR]

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]

The taxonomy and phylogeny of the pufferfishes belonging to the family Tetraodontidae found in India are poorly understood. We investigated five species of freshwater and marine pufferfishes using partial sequences of 16S rRNA and cytochrome c oxidase subunit I ( COI) of mitochondrial genes. The sequence alignment of 16S rRNA yielded 573 bp, whereas COI gene sequence alignment yielded 614 bp. The sequence analysis of the genes revealed two distinct groups of freshwater and marine origin, which are genetically distinct from each other and exhibit identical phylogenetic resolution. The partial sequences of both the genes provided sufficient phylogenetic resolution to distinguish all the five species of pufferfishes. The COI sequences could be used as DNA barcodes for identification of the pufferfishes. [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]

There has been an increasing demand for alien fish species in India. However, environmental, socioeconomic and biodiversity issues are important considerations when regulating the unauthorized culture and spread of alien species. Information collected in the present review revealed the presence of over 300 alien species imported intentionally or illegally; 291 ornamental species, 31 aquaculture species and two larvicidal fishes. Field data demonstrated the widespread occurrence of some of the world's worst invasive species, for example, Cyprinus carpio, Oreochromis niloticus, Aristichthys nobilis, Pygocentrus nattereri and Pterygoplichthys spp., in inland waters; other species are emerging as a threat to aquatic biodiversity. The benefits and risks of alien species were analysed and the impact was quantified using a simple developed 'Fish Invasiveness Screening Test' (FIST). Our information suggests that alien species, despite possessing some attractive culture characteristics, generally reduce the availability of local species and establish in natural water bodies becoming invasive and consequently adversely affecting fish biodiversity and aquatic ecosystems. In light of the adverse ecological impacts of alien species, we developed strategic regulations and quarantine procedures and advised aquaculturists to strictly follow them to contain potential and plausible menaces. [ABSTRACT FROM AUTHOR]

Background. The Ganga River (Ganges) is known of its rich fish diversity which is adversely affected by degrading environmental and ecological conditions. There are more than 300 exotic fish species in India. Many of them (particularly Cyprinus carpio) escaped from confinement and are now present in the Ganga River, challenging its ecological equilibrium. The aim of this project was to study the population characteristics of Cyprinus carpio (i.e., the abundance, size range, food and feeding, gonado-somatic index (GSI), gonad maturity stage, maturity and breeding) and the altered fishery dynamics. Materials and Methods. The commercially caught fishes, including the exotic ones, were identified, examined and measured. Important indices such as: the abundance index of exotic fishes, the gonado-somatic index (IG), as well as the gonad maturity stage of the escapee C. carpio were determined. The gut content was also analyzed to identify food items and thereafter the food richness, diet breadth, and gut repletion index (GRI%) were calculated using the Simpson's diversity index. Results. C. carpio introduced about sixty years ago for aquaculture has now been found to invade into the Ganga, the largest river of the country contributing significantly to the fishery. The abundance index of C. carpio ranged from 12.2% to 45.5 % in 250 km long river stretch of the Ganga River flowing along Kanpur to Varanasi in the state of Uttar Pradesh. The gut content analysis revealed the presence of Eichhornia (9.8%), Pistia (11.6%), Nymphaea (8.5%), annelids worms (7.8%), algae (20.2%), mud and detritus (14.8%). The calculated diet breadth ranged from 0.82% to 0.91%; food richness ranged from 12 to 16, and the gut repletion index (GRI%) was 100% at different sampling sites. Mature females represented all the six reproductive stages with varying gonadosomatic index (IG) (0.5 to 30) in different catches. Presence of spent, ripe, and mature females was recorded. Conclusion. Abundance of exotic fish primarily C. carpio and Oreochromis niloticus in the fishery of the Ganga River was observed. The gonado-somatic index (IG) and the presence of all the six gonadal stages confirmed that C. carpio established its breeding population. The dominant catch of exotic fishes negatively impacted on the important indigenous fishes particularly Indian major carps (Catla catla, Labeo rohita, and Cirrhinus mrigala). The change in dynamics of the fishery due to the presence of common carp attracted attention to conserve rich indigenous germplasm facing threats of shifting from their natural habitats. [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.

Genetic diversity in the Indian population of the tiger shrimp Penaeus monodon was determined by using partial sequence data of the mitochondrial DNA (mtDNA) control region (D-loop) and the 16S rRNA gene. Eight populations from different geographical locations (Mumbai, Kochi, Mangalore, Kakinada, Gopalpur, Chilika, Paradeep and Andaman) were collected and analysed. The amplified polymerase chain reaction products of size 577 bp for the control region and 472 bp for 16S rRNA were sequenced in both directions and data were analysed throughclustal,arlequin,mega andphylip. A significant genetic structure was found among the Indian populations. The mtDNA control region proved to be a powerful marker in comparison with 16S rRNA for population studies of this species. The east coast population was more genetically diverse than the west coast. The Andaman population was found to be the most diverse among all the populations. The populations on the west coast were found to be genetically more structured and differentiated than the populations on the east coast. The results revealed a high level of genetic diversity and also distinct population structuring of P. monodon, suggesting great possibilities of genetic improvement for growth and other economic traits. [ABSTRACT FROM AUTHOR]

Two new cell culture systems namely epitheloid cells of Lates (LCE) and fibroblastic cells of Lates (LCF) have been developed from fry and fingerling of the economically important brackishwater fish Lates calcarifer. Primary cultures were initiated by explant technique using caudal fin of fingerling and whole body tissue of the fry. The nutritional requirements and the growth pattern in response to different culture environment were similar for the two cell cultures. The culture medium used was Leibovitz-15 supplemented with 20% fetal bovine serum (FBS) and 1% fish serum. The LCE comprised of epithelioid cells and LCF cells were fibroblastic. With a split ratio of 1:2, the confluency of cells was attained in 8–10 days at an incubation temperature of 28°C. The cells were found to grow well in a wide range of temperature (24–32°C) and stable at 20 and 36°C. The growth rate of LCF and LCE cells increased proportionately with the concentration of FBS from 5% to 20%. A decrease of serum level to 10% after eight subcultures produced no apparent change in cell morphology and growth rate. The viability of cells was found to be 70% when revived after a month of storage in liquid nitrogen (−196°C). [ABSTRACT FROM AUTHOR]

Artemia nauplii cultured for 24 h in lipid-enriched media contained 0, 0.38, 1.67, 0.79, 5.71 and 5.14 ng 17α-methyl testosterone (MT) mg−1 dry weight for the control, 5, 15, 30, 50 and 100 mg of 17α-MT L−1 of media respectively. Giant fresh water prawn Macrobrachium rosenbergii larvae were fed hormone-enriched Artemia nauplii for 50 days. A significant difference in sex ratios (0.92, 0.69 and 0.93) was obtained in relation to the control group. These results suggest that further research is needed with regard to standardization of doses and duration of treatments for complete hormonal control of sex differentiation in M. rosenbergii. [ABSTRACT FROM AUTHOR]

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.)

Two new cell lines (CCF and CCH) were established from fin and heart tissues of common carp, Cyprinus carpio. The cells were optimally maintained in Leibovitz-15 medium supplemented with 10% fetal bovine serum (FBS) and 10 ng/ml of basic fibroblastic growth factor (bFGF). The effects of temperature, concentration of FBS and bFGF on the growth of CCF and CCH cells were examined. The temperature ranged from 24 to 32°C for good growth of the cells. The growth rate of cells was higher in medium containing 10% FBS and the addition of bFGF to the medium significantly increased the growth rate. The CCF cells were found to be epithelial, while the CCH cells were fibroblastic in nature. The cytogenetic analysis of the cell lines revealed a diploid number of 100 chromosomes in C. carpio. The viability of CCF and CCH cell lines were 70 and 72%, respectively, after six months of storage in liquid nitrogen (-196° C). Molecular characterization of the cell lines using 16S rRNA and Cytochrome Oxidase Subunit I (COI) revealed the origin of the cell lines. These new cell lines will be useful for isolation of fish viruses and other in vitro biotechnological studies.