Indian Council of Agricultural Research
CENTRAL MARINE FISHERIES RESEARCH INSTITUTE

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Detection of betanodavirus in wild caught fry milk fish,Chanos chanos

Betanoda virus was detected in wild caught milk fish fry (Chanos chanos) exhibiting Beta noda virus was detected in wild caught milk fish fry (Chanos chanos) showing typical clinical symptoms and signs of viral nervous necrosis (VNN)/ Viral encephalopathy and retinopathy, (VER) from the bank of Matchlipattinam, Andhra Pradesh, India during March 2014. Mortality of these fry was observed within a few days after stocking and attained 100 % in next few days. The larvae infected by the virus showed typical swimming behavior which included positioning in a vertical manner with a whirling type movement; sinking to the bottom, darting or swimming in a corkscrew fashion; belly-up at rest, abnormal body coloration (pale or dark) and over inflation of swim bladder. Severe pathological changes in the form of vacuolation and necrosis in brain and other organs such as spinal cord, and retina of the eyes further confirmed the infection by this virus. The earliest occurrence of diseases was less than 30 days of post-hatch, less than 35 mm total length. Usual mortality rate varied from 50-80 % with highest mortality rate up to 100 % in wild caught milk fishes. Amplification of the virus RNA2 region by RT-PCR of Beta noda virus yielded a product of 430 bp .

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Morphological and molecular characterization of Chloromyxum argusi n. sp. (Myxosporea) infecting urinary bladder of Scatophagus argus

The present paper describes a new species of Chloromyxum infecting the urinary bladder of the estuarine fish, Scatophagus argus, from the southwest coast of India. The parasite exhibited an overall prevalence of 41.93%; the prevalence is influenced by host size and seasons. Mature spores are subspherical, measure 9.40 ± 0.66 by 9.32 ± 0.87 ?m, and are characterized by the presence of sutural and extra-sutural ridges, binucleated sporoplasm, and a pair of caudal extensions. Four pyriform, unequal polar capsules with raised polar filament discharge pores and ribbon-like polar filaments are present. Polar filament coils numbered four to five in large polar capsules and three in small polar capsules. Pansporoblast is irregular with granulated cytoplasm and has fine villosites on its surface. Plasmodia are spherical/irregular with monosporic and polysporic forms. In molecular and phylogenetic analysis, the myxosporean stands out with a high bootstrap value and was positioned as a sister branch of Chloromyxum kurisi. In view of the morphologic, morphometric, and molecular differences with the existing species of Chloromyxum, and considering the differences in hosts and geographic locations, the present species is treated as new and the name Chloromyxum argusi n. sp. is proposed.

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Records of rare elasmobranchs and their biological observation from the north-eastern Arabian Sea, off Mumbai

Present study consists rare batoids from north-eastern Arabian Sea. A specimen of Dasyatis microps (101.0 cm DW) and Pteroplatytrygon violacea (49.5 cm DW) respectively were collected in a trawler, operating south off Mumbai in the Arabian Sea, north-west coast of India. The present record of these elasmobranchs from the northern Arabian Sea shows their extended range of occurrence around the Indian coast, which is earlier reported from south-east and south-west coast of India. The morphometric measurements of the specimens collected were compared with previous records. In the same fishing area, pregnant Rhynchobatus djiddensis (254.0 cm TL) and a juvenile R. djiddensis (44.0 cm TL) was also caught in shallow coastal waters at 40 m depth. Biological observations on Dasyatis microps and Rhynchobatus djiddensis also presented.

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Previously undescribed antioxidative O-heterocyclic angiotensin converting enzyme inhibitors

Four previously undescribed antioxidative O-heterocyclic analogues, characterized as 3?-isopropyl-3c-{3b-[(2- oxo-3,4-dihydro-2H-chromen-3-yl) methyl] butyl}-2?-butenyl-3?-hydroxy-2?-(2?b-methoxy-2?-oxoethyl)-3?, 4?- dihydro-2H-pyran-4?-carboxylate (1), 2c-methylbutyl-6-[6c-(benzoyloxy)propyl]-6-methyl-tetrahydro-2Hpyran- 2-carboxylate (2), 6-{6b-[3?-(5?a-methyl propyl)-3?, 4?-dihydro-2H-pyran-6?-yl] ethyl}-tetrahydro-2Hpyran- 2-one (3) and 7-(7c-methylpentyl)-hexahydro-2H-chromen-2-one (4) were isolated from the ethylacetate: methanol fraction of the brown seaweed Sargassum wightii. Nuclear magnetic resonance and mass spectroscopic experiments unambiguously attributed their structural identities. Antihypertensive activities of the studied compounds were determined in terms of their angiotensin converting enzyme (ACE) inhibitory potential. The 2H-pyranylcarboxylate derivative (1) displayed comparable activity (IC50 0.08 mg/mL) with standard antihypertensive agent captopril (IC50 0.07 mg/mL). The O-heterocyclic derivatives bearing 2H-pyran-4?-carboxylate (1) and 2H-pyran-2-carboxylate (2) frameworks showed significantly greater (p < 0.05) 1, 1-diphenyl-2- picryl-hydrazil radical quenching potential {IC50 (1) 0.34 and IC50 (2) 0.45 mg/mL} compared to the standard antioxidant ?-tocopherol (IC50 0.63 mg/mL). Structure-activity relationship analyses demonstrated that the electronic and lipophilic descriptors might significantly contribute towards the target bioactivities of 2H-pyranylcarboxylates (1 and 2). Molecular docking simulations were carried out for ACE inhibition, and the binding energy obtained for the compounds (~7.04–8.48 kcal/mol) demonstrated their potential enzyme-ligand interactions. The potential of hitherto undescribed O-heterocyclic derivatives as natural antioxidant and antihypertensive functional food supplements and their utilization as therapeutic leads in the antihypertensive management were described in the present study.

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Troubled waters: Threats and extinction risk of the sharks.

The extinction risk of sharks, rays and chimaeras is higher than that for most other vertebrates due to low intrinsic population growth rates of many species and the fishing intensity they face. The Arabian Sea and adjacent waters border some of the most important chondrichthyan fishing and trading nations globally, yet there has been no previous attempt to assess the conservation status of species occurring here. Using IUCN Red List of Threatened Species Categories and Criteria and their guidelines for application at the regional level, we present the first assessment of extinction risk for 153 species of sharks, rays and chimaeras. Results indicate that this region, home to 15% of described chondrichthyans including 30 endemic species, has some of the most threatened chondrichthyan populations in the world. Seventy?eight species (50.9%) were assessed as threatened (Critically Endangered, Endangered or Vulnerable), and 27 species (17.6%) as Near Threatened. Twenty?nine species (19%) were Data Deficient with insufficient information to assess their status. Chondrichthyan populations have significantly declined due to largely uncontrolled and unregulated fisheries combined with habitat degradation. Further, there is limited political will and national and regional capacities to assess, manage, conserve or rebuild stocks. Outside the few deepsea locations that are lightly exploited, the prognosis for the recovery of most species is poor in the near?absence of management. Concerted national and regional management measures are urgently needed to ensure extinctions are avoided, the sustainability of more productive species is secured, and to avoid the continued thinning of the regional food security portfolio.

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First Record of Arrow Gaper, Champsodon sagittus Nemeth

Champsodon sagittus, a species belonging to group popularly known as gapers has earlier known to occur in a narrow region of Indo-pacific along the coast of Australia, Philippines and Indonesia. The current report is the first record of the species from the Bay of Bengal, suggesting its possible wider distribution of the species in Indo-pacific Ocean. C. sagittus can be separated from other congeneric species by the combination of two gill rakers of upper limb, naked belly, five pair of sensory papillae on snout and no expansion of haemal spine The study also gives an insight into its depth of occurrence and habitat sharing with deep sea crustaceans.

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