Histomorphology and immunohistochemistry of adenocarcinoma and fibroma in Indian oil sardine (Sardinella longiceps Valenciennes, 1847) from Palk Bay, Southeast coast of India

A single specimen of Indian oil sardine Sardinella longiceps was observed with wart-like appearances in three different regions of the fish: one on the premaxillary part, and other two on the skin and at the vent region respectively. Mucosal tissues were expunged and preserved in 10 % neutral phosphate-buffered formalin for histological examination. Based on the histopathological analysis, lesions were identified as adenocarcinoma and fibroma on the premaxillary part and skin, respectively. Based on the immunohistochemistry, vimentin and cytokeratin-like proteins were demonstrated, suggesting that the wart-like extrusions were fibroma and adenocarcinoma respectively

Comparing eDNA metabarcoding and conventional pelagic netting to inform biodiversity monitoring in deep ocean environments

The performance of environmental DNA (eDNA) metabarcoding has rarely been evaluated against conventional sampling methods in deep ocean mesopelagic environments. We assessed the biodiversity patterns generated with eDNA and two co-located conventional methods, oblique midwater trawls and vertical multinets, to compare regional and sample-level diversity. We then assessed the concordance of ecological patterns across water column habitats and evaluated how DNA markers and the level of sampling effort influenced the inferred community. We found eDNA metabarcoding characterized regional diversity well, detecting more taxa while identifying similar ecological patterns as conventional samples. Within sampling locations, eDNA metabarcoding rarely detected taxa across more than one replicate. While more taxa were found in eDNA than oblique midwater trawls within sample stations, fewer were found compared to vertical multinets. Our simulations show greater eDNA sampling effort would improve concordance with conventional methods. We also observed that using taxonomic data from multiple markers generated ecological patterns most similar to those observed with conventional methods. Patterns observed with Exact Sequence Variants were more stable across markers suggesting they are more powerful for detecting change. eDNA metabarcoding is a valuable tool for identifying and monitoring biological hotspots but some methodological adjustments are recommended for deep ocean environments

Hybrid in vitro diffusion cell for simultaneous evaluation of hair and skin decontamination: temporal distribution of chemical contaminants

Most casualty or personnel decontamination studies have focused on removing contaminants from the skin. However, scalp hair and underlying skin are the most likely areas of contamination following airborne exposure to chemicals. The aim of this study was to investigate the interactions of contaminants with scalp hair and underlying skin using a hybrid in vitro diffusion cell model. The in vitro hybrid test system comprised “curtains” of human hair mounted onto sections of excised porcine skin within a modified diffusion cell. The results demonstrated that hair substantially reduced underlying scalp skin contamination and that hair may provide a limited decontamination effect by removing contaminants from the skin surface. This hybrid test system may have application in the development of improved chemical incident response processes through the evaluation of various hair and skin decontamination strategies.Peer reviewedFinal Published versio

पश्चिम बंगाल तट की समुद्री मात्स्यिकी: 2021

वर्ष 2021 के दौरान पश्चिम बंगाल का कु ल समुद्री मछली अवतरण 1.4 लाख टन आकलित किया गया, जिसमेें वर्षवर्तमान 2020 के अवतरण (2.6 लाख टन) (चित्र.1) की तुलना मेें 47% की घटती देखी गयी। वर्तमान कोविड 19 महामारी के साथ विविध चक्रवाती घटनाओ और डीज़ल मूल्य मेें हुई वृद्धि से मत्स्यन दिनोों (मत्स्यन प्रयास) मेें हुई कमी के कारण मछली अवतरण की घटती हुई

Diversity and present status of croaker fishery along Odisha Coast

Croakers are locally called as “Patharamundi”, “Sila” or “Borei” are commercially important demersal resources exploited all along the Odisha coast. The diversity and status of croaker fishery along Odisha coast in the Bay of Bengal is reported. Landings of croakers showed an increasing trend over the decades with lowest catch recorded in 1976 (333 tonnes) and peaked in 2011 (46,468 tonnes) after which the catch has been declining till 2018. Among the maritime states of India, Odisha, contributing 20,625 tonnes accounting for 18% of the country’s total croaker landings in 2020, showed a tremendous increase compared to the previous year. It was a significant component in the trawl catches forming 34% of the total demersal fish landings and 12% of the total marine fish landings of Odisha. Lesser sciaenids (49%) dominated the croaker landings. They were caught by various gears such as trawl nets, gillnets, hook & line, ringseines, and shoreseines. Bulk of the catches were taken by trawl nets (73%) followed by gillnets (22%). More than 20 species contribute to the fishery of which the major species were “lesser sciaenids” such as Johnius carutta (40%), Pennahia anea (30%), Panna heterolepis (12%), Kathala axillaris (9%), Nibea maculata (5%). Otolithes ruber (66%), Chrysochir aureus (23%), Pterotolithus maculatus (7%) dominated in the “intermediate sciaenids” and Otolithoides pama among the “greater sciaenids” with 98% contribution. Protonibea diacanthus locally called as “Telia” is gaining attention among the fishermen in the recent past due to their high quality swim bladders which are used for the production of isinglass for export. As compared to previous years, the lowest catch was reported in 2020 (0.30 tonnes) probably due to non-fishery causes such as Covid pandemic which affected general fishing activities.However, continuous monitoring and management of this economically important species is required. Juveniles and young adults of several species of croakers in bottom trawls as bycatch can cause an economic loss to the fishery sector and require management measures

Morphological Variation Among Herring Gulls (Larus Argentatus) And Great Black-Backed Gulls (Larus Marinus) In Eastern North America

Herring Gull (Larus argentatus) and Great Black-backed Gull (L. marinus) morphometric data from various eastern North American locations was collected to examine the sources of variation in body size within and among geographic regions. For Herring Gulls, significant differences in all commonly taken measurements at local and regional scales were found. However, most of the variation in measurements was due to sex differences and the natural variance seen within local populations. Herring Gulls breeding in the Arctic did not show any evidence of being morphologically different from other groups. A discriminant function derived from a Newfoundland, Canada, breeding population of Herring Gulls successfully assigned the sex of birds in Atlantic Canada and Nunavut, Canada, further emphasizing that most of the variation seen is between sexes and not among local or even regional populations. It also indicates that the evitable variation introduced by inter-individual differences in measurements was insufficient to compromise the utility of the discriminant function. The correct classification rate was lower for Great Lakes breeding Herring Gulls, indicating that these birds have different morphologies than those of populations in easterly regions. In contrast, few differences and no clear geographic patterns were found in measurements for Great Black-backed Gulls. These results were consistent with recent genetic information, suggesting an older west to east radiation of Herring Gulls across North America and a lack of isolation among Great Black-Backed Gull populations

Stock identification of tiger tooth croaker Otolithes ruber (Schneider, 1801)

The tiger toothed croaker Otolithes ruber (Schneider, 1801) of the family Sciaenidae is a demersal fish that contributes significantly to the marine landings of India. To identify stock units of O. ruber based on body shape morphometry, truss network analysis was carried out based on specimens collected from four selected locations, two each from east coast (Digha and Chennai along Bay of Bengal) and the west coast (Cochin and Ratnagiri along Arabian Sea) of India. A total of 20 truss distances along the fish surface, including head, mid body and posterior region were measured and transformed measurements were subjected to factor analysis and discriminant function analysis. The bivariate plot score of factor analysis indicating two distinct stocks on both the coasts may be the consequence of geographical isolation and different environmental conditions along the Bay of Bengal (east coast) and Arabian Sea (west coast). The Ratnagiri and Cochin population showed considerable mixing which indicated the presence of a unit stock along the west coast. However, existence of strong morphometric differentiation between Digha and Chennai populations indicated two separate spawning populations in the Bay of Bengal. In the cross-validation of Discriminant function analysis, the most well classified group was Digha population (97.85%). The present study suggests the possible existence of three stocks of O. ruber, one in west coast (Cochin and Ratnagiri) and two in east coast (Digha and Chennai) which can be considered while formulating effective management strategies for the species

ओड़़ीष़ा तट की समुद्री मात्स्यिकीः 2020

ओड़़ीष़ा तट की समुद्री मात्स्यिकीः 202

Decadal status of Large Pelagic fishery in West Bengal

The marine landings of the state have fluctuated widely over the years with the maximum of 4 lakh tonnes recorded in 2011. Pelagics dominate the marine fishery and contribute around two-third of the marine landings. Major large pelagic resources landed were seerfishes, queenfishes, tunas and cobia. Sporadic landings of barracudas, billfishes and dolphinfish were observed in certain years. Average annual landings of large pelagics during 2010 – 2019 were 6,131 t forming 2.65% of the total state landings. More than half of the landings were contributed by seerfishes, followed by queenfishes. Major gears contributing to the landings were gillnets (60%) and trawl nets (38%). Scomberomorus guttatus formed 95% of the seerfish landings and were landed by both trawl nets and gill nets, whereas Scomberomorus commerson landed only by gillnets. Among queenfishes landed by trawl nets and gill nets, Scomberoides lysan dominated followed by S.tala and S.commersonianu