Nutritional Stress And Ascorbic Acid Dynamics: Gender Perspectives In Clarias Batrachus

The current study investigates the impact of starvation on the levels of ascorbic acid in the brain and hepatic tissues of both male and female Clarias batrachus. Male individuals exhibited a significantly greater concentration of ascorbic acid compared to female individuals. Under typical circumstances, the brain contains higher levels of ascorbic acid (43.24mg/100gm in males and 40.65mg/100gm in females) compared to the liver (17.59mg/100gm in males and 13.32mg/100gm in females). Extended nutritional stress leads to a gradual decrease in the level of ascorbic acid in all types of tissues, which could be associated with an increase in gluconeogenesis. The liver exhibited a higher level of depletion (73% in males and 78% in females), whereas the brain showed a lower level of depletion (57% in males and 48% in females) following a period of 40 days of hunger

Modes of action of the current Priority Substances list under the Water Framework Directive and other substances of interest

The Water Framework Directive 2000/60/EC (WFD) has established a strategy for water protection that includes specific measures for pollution control to achieve good chemical and ecological status at European level. There is a need to review the approach to the current listing of priority substances (PS) under the WFD and to the current assessment of the chemical status, and consider eventually a wider range of chemical substances that could be covered in future monitoring programmes. Overall, the aim is to assess the water status more holistically and understand which the real effects are caused by the sum of the chemical substances present in the aquatic environment (including emerging pollutants /other substances of interest, metabolites and transformation products). The assessment of chemical status should be improved and linked with ecological status where relevant. Hundreds of different substances may co-occur, and even if most are present at very small concentrations they could exert a toxic effect on aquatic organisms (Carvalho et al. 2014) exposed for their entire life cycle and indirectly on human health (via food and drinking water consumption). Some of the substances in the current list of Priority Substances and in the first Watch List are considered in groups (e.g. brominated diphenylethers, neonicotinoid insecticides), but the overall approach to chemical pollution is otherwise based on the regulation of single substances. It has become increasingly clear that the risks from the vast number of chemical substances present in the environment cannot be adequately controlled on this basis. The Commission acknowledges the need to consider the potential toxic effects of mixtures of chemicals (EC COM(2012)252, 7th EAP). The challenge is to find a way of capturing a true picture of the chemical status of water bodies based on standards and methods that assess the presence of an adequate range of representative chemical effect types or modes of action (MoA), for example. The knowledge on the MoA is an important driver for linking exposure to chemicals to their effects in the aquatic environment, and therefore for development and application of the scientific methodologies for the assessment of combined effects of chemicals - the effect-based methods (EBM). The EBM, including biomarkers and bioassays, can target different levels of biological organisation in the aquatic environment, such as individual and/or sub-organism, community, and population levels (Carvalho et al. 2014, Ann-Sofie Wernersson et al. 2014). It is however much less clear how these EBM can be used to capture (predictively) the indirect effects that might occur in humans following long-term chronic exposure to pollutants via the aquatic environment. The use of effect-based monitoring approaches, complementary to chemical analysis, could allow assessing chemical status more holistically (rather than with a limited but ever-growing list of individual substances). The use of the EBM offers also the advantage of overcoming analytical difficulties (Kunz et al. 2015) and reducing monitoring costs by screening. To become a credible complement to chemical monitoring information, however, a better understanding of the capabilities and gaps of available EBM is needed. This report, based on a comprehensive literature study, reviews the current PS list and other substances of interest, considering their MoA(s). The review of data from the open sources clearly identified few groups of toxicological endpoints, with the majority driven by non-specific mechanisms (e.g. oxidative stress, activation of metabolizing / detoxifying pathways, histopathology, and others), and few groups with more specific biochemical / physiological pathways (photosynthesis inhibition, acetylcholinesterase inhibition, presence of PAHs metabolites, expression of metallothioneins). The majority of current PS and other substances of interest can be grouped, based on few common toxicological endpoints, and biomarkers are available for determining the concentrations and/or effects of some groups of substances. The identified biomarkers of effect seem to be however in general not very specific. There is clearly no “one size fits all” bioassay / EBM that could provide the toxicological potency of every PS and other substances of interest and their mixture toward all aquatic organisms in all water bodies, but rather a battery of bioassays that should be selected as “fit for purpose”. In addition, the present report allowed identification of uncertainty and inconsistency in observations, and thus identified areas where future investigations can be best directed. The present knowledge about MoA(s) remains limited, especially for the emerging substances of concern, such as pyrethroids and neonicotinoides.JRC.D.2-Water and Marine Resource

Studies on the reproduction of Indian whiting Sillago sihama (Forskal) (Percoidei, Sillaginidae)

In the present work, basic aspects of maturation and spawning, salient features of gametogenesis and associated biochemical changes occurring during these processes in an important cultivable fish, Sillago sihama belonging to the family Sillaginidae have been investigated The fishes belonging to the family Sillaginidae, commonly known as 'sand whitings' or 'sand borers', are distributed in the shallow estuarine and near coastal waters of Indo-West Pacific region. Few species are also known to ascend the freshwater regimes of the river. The sillaginids contribute to small but commercially important fisheries throughout the range of their distribution (Mckay, 1985)

Pathology of aflatoxicosis and Heavy metal toxicity in pearl Spot Etroplus suratensis (Bloch) (Th 129)

Food and water are the two major routes through which aquatic organisms are exposed to exogenous hazardous toxic insults. The pathology of the toxic impacts due to a food contaminant (aflatoxin B, or AFB,) and an environmental pollutant (cadmium) was studied in pearl spot, Etrop/us suratensis (Bloch). The influence of these two toxicants on various physiological indices as well as vital organs of the fish was studied in two separate experiments by exposing the fishes to either 400 ppb of AFB, or 9.4 ppm of cadmium for a period of 8 weeks. The physiological alterations due to aflatoxin exposure includes, an initial decrease followed by an increase in erythrocyte count; increase in leucocyte count, packed cell volume (PCV), serum alkaline phosphatase, aspartate aminotransaminase (AST) and alanine aminotransaminase (AL T); and a decrease in serum proteins. Histopathological and ultrastructural studies revealed progressive degenerative changes in the vital organs, liver, kidney, spleen and thymus. Liver sections revealed biliary proliferation and presence of pleomorphic, polyhedral and basophilic megalocytes invading into the normal parenchyma, which was diagnosed as hepatocellular carcinoma. The electronmicrographs revealed dilatation, fragmentation , proliferation and whirl formation of endoplasmic reticulum (ER), mitochondrial damages like condensation and loss of cristae and granules, nuclear changes like presence of perichromatin and chromatin granules, electron dense inclusions and presence of autophagosomes in the cytoplasm. The toxic insults due to cadmium were manifested as increase in ESR, AST and AL T and a decrease in PCV, serum proteins and alkaline phosphatase activity. Liver, kidney, spleen, thymus and gills exhibited severe degenerative changes at cellular and subcellular levels. Liver revealed coagulative necrosis and fibroblastic proliferation . The renal tubular epithelial cells were desquamated and periglomerular thickening as well as increased nuclearity were observed in glomeruli. The secondary lamellae of gills were elongated and fused together in cadmium exposed fishes. The major ultrastructural changes in the vital organs include ER fragmentation, mitochondrial swelling, presence of multivesicular bodies, autophagia, damage to desmosomes and cell membranes

Renaissance in Fisheries: Outlook and Strategies - Book of Abstracts 9th Indian Fisheries Forum, December 19-23, 2011, Chennai, India

The Asian Fisheries Society – Indian Branch (AFSIB) since its inception in 1986, has been providing a platform for discussion at the national level on issues related to research, development, education and policies by organizing Indian Fisheries Forum (IFF) every three years in different parts of the country. The 9th Indian Fisheries Forum (9th iff) will be hosted by the Central Marine Fisheries Research Institute (CMFRI), at Chennai during 19-23 December 2011. The main theme of the 9th iff is “Renaissance in Fisheries: Outlook & Strategies”. It would have a comprehensive look for the fisheries and aquaculture sectors, for achieving greater synergy among the stakeholders and planning strategies for capture fisheries and aquafarming to build higher levels of sustainability and profitability. The forum would also address the issues of impact of climate change and its mitigation, resource constraint and species diversification for the expansion of fish production activity; and encourage young scientists to undertake need-based and resource specific research. An international symposium sponsored by the Bay of Bengal Large Marine Ecosystem (BoBLME) is scheduled to be held during the forum on 21 December, 2011 with theme: Bay of Bengal–Ecosystem Approach to Fisheries Management

Annual report 1980

An overview of the 1980 activities of the center is presented. The aquaculture research presently underway at each research station is briefly reviewed