Influence of certain environmental parameters on mass production of rotifers: A review

Larviculture of many finfishes and crustaceans in aquaculture depends mainly on the live feed and its unavailability in sufficient quantity is hampering its expansion and culture progress all around the world. The most suitable feed for marine finfish larvae is the commonly available zooplankton species such as rotifer, copepods and Artemia nauplii. Among all, the live feed that has been demonstrated more successfully as the first feed for most of the marine finfish species is rotifer. Optimum conditions are required for better growth, reproduction and increased productivity of rotifers. The major factors that influence the population size of rotifer are temperature and salinity. Hence, the impact of environmental parameters with special focus on the salinity and temperature on the increase in biomass and smaller rotifer production is of utmost importance in the present scenari

Seasonal occurrence of potential fishing zones along northern Andhra Pradesh coast

228-232Data on potential fishing zones (PFZ), obtained from the Indian National Centre for Ocean Information Services (INCOIS), Hyderabad, and advisories for North Andhra coast were segregated season wise and analyzed to understand the trends and the frequency of occurrences of PFZ in North Andhra coast. Plotting of data revealed location of PFZ near coastal regions during summer months. These zones moved towards deeper waters during pre-monsoon, expanding to a larger area as the monsoon progressed and moved north during post-monsoon season. Plotting also revealed that Kakinada waters have frequent PFZ hits especially nearer to the Kakinada bay. Visakhapatnam waters were observed to get high intensity of PFZ hits during Monsoon followed by those during post-monsoon and summer seasons. However in Kalingapatnam waters, high intensity of PFZ occurred during post-monsoon followed by monsoon and summer seasons

Prevalence of marine litter along the Indian beaches : A preliminary account on its status and composition

Beach litter are man-made objects discarded directly or indirectly. This study brings out synoptic picture of status and composition of beach litter from 254 selected beaches along the maritime States of Peninsular coast of India as well as the Union Territories of Andaman and Lakshadweep Islands from the one time observation conducted between October 2013 and January 2014 for the first time. These beaches were classified and graded with colour codes according to the levels of beach litter. Beach litter from different maritime States and the UTs showed that Odisha coast has the lowest (0.31 g/m2) quantity and Goa coast (205.75 g/m2) the highest quantity of beach debris. Archipelagic coasts of Andamans as well as Lakshadweep recorded values higher than Kerala, Tamil Nadu, Andhra Pradesh, Odisha and West Bengal. Samples of debris collected from beaches revealed that all the items were domestic and anthropogenic discards. Plastic litters such as single use carry bags and sachets of soft drinks, edible oils, detergents, beverages, cases of cosmetics, toothpaste, PET bottles, ice cream containers etc., recorded highest mean of 25.47g/m2 from Goa coast and the lowest (0.08 g/m2) from Odisha. The relative percentage of mean values of plastic (B group) items in beach debris along the Indian coast registered highest mean percentage from Maharashtra (81 %) and the lowest mean from beaches of Andhra Pradesh (7%). The two island Union Territories registered 40% (Lakshadweep) and 47% (Andamans) of plastics over the total debris, while the national average was only 14%. Available online at: www.mbai.org.in doi: 10.6024/jmbai.2017.59.1.1953-03 Out of the total 254 beaches surveyed, 51 beaches were graded as very clean with green (<1 g/m2) colour, 122 beaches were graded as Clean and depicted by blue colour. Beaches of very clean grade (<1 g/m2) were found in Kerala (17), Maharashtra (12), Tamil Nadu (2), Andhra Pradesh (4), Odisha (7) and West Bengal (3). Whereas extremely littered beaches (>100 g/m2) were found in Karnataka (13), Goa, Gujarat, and Andaman Island. With reference to the coastal population and per capita share of beach debris, Goa registered highest values (40.97 kg/head) and the Odisha coast registered the lowest values (0.005 kg/head)

Planktonic diversity in Indian waters

Phytoplankton is microscopic, plant-like organisms that drift in the water. These singlecelled photo synthesizers can either swim using their flagella or be carried by the currents. They are an essential part of aquatic food chains and are found in almost all bodies of water. German biologist Victor Hensen first used the term "plankton" in 1887 to describe these microorganisms

செயற்கை திட்டுகள் ஓர் அறிமுகம், வரையறைகள், வரலாறு மற்றும் இந்தியாவில் அவற்றின் பயன்பாட்டு நிலை

Artificial reefs - definition, history and status in India: World fisheries today face threats from several quarters, including non-judicious fishing practices influenced by irrational growth in demand, destruction of aquatic habitats through pollution and destructive fishing methods, rupture of trophic food webs by increased exploitation of particular fishery resources, increased incidences of natural disasters and the impacts of climate change. With increasing concern over global marine fish production, and the scenario being not very different in India, there is an urgent need to evolve resource-, area-, and habitat-specific management tools to revive, sustain or improve Indian marine fisheries and marine ecosystems. The immediate and primary objective of a management strategy would ideally look towards enhancing fish catches

Artificial reefs - definition, history and status in India

World fisheries today face threats from several quarters, including non-judicious fishing practices influenced by irrational growth in demand, destruction of aquatic habitats through pollution and destructive fishing methods, rupture of trophic food webs by increased exploitation of particular fishery resources, increased incidences of natural disasters and the impacts of climate change. With increasing concern over global marine fish production, and the scenario being not very different in India, there is an urgent need to evolve resource-, area-, and habitat-specific management tools to revive, sustain or improve Indian marine fisheries and marine ecosystems. The immediate and primary objective of a management strategy would ideally look towards enhancing fish catches

कृत्रिम चट्टान - परिभाषा, इतिहास और भारत में स्थिति

कृत्रिम चट्टान - परिभाषा, इतिहास और भारत में स्थित

Preliminary estimates of potential areas for seaweed farming along the Indian coast

India has enormous potential for seaweed mariculture; however, mass scale commercial farming of seaweeds is yet to take off successfully in the country. R&D efforts over the years have resulted in techno-scientific improvements in farming technologies such as floating rafts, net-tubes, long-lines, and cage based IMTA systems for seaweed culture. However, a few challenges remain, particular in identifying potential sites, its demarcation and developing suitable and sustainable spatial plans for seaweed farming on a country-wide, commercial perspective. In view of the emerging importance of seaweed mariculture and policy thrust by the Government of India, an all India preliminary site selection survey suitable for seaweed farming was conducted by ICAR-CMFRI along all maritime states of India. From this survey a total of 23,970 ha area were identified as potential seaweed farming along the Indian coast. In the present article, we present details of the suitable sites and its demarcation on a preliminary spatial map for facilitating the imminent expansion and effective adoption of seaweed farming in the country

Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.

Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant

Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity

Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant