14 research outputs found
Comparison of effectiveness of heat and cold shocks applied in the induction of gynogenesis in Clarias gariepinus (Burchell)
An experiment was conducted to optimize the procedure of gynogenesis in African catfish, Clarias gariepinus by suppressing meiotic and mitotic cell divisions in fertilized eggs. Gynogensis was conducted by fertilizing normal eggs with UV-irradiated sperm followed by either heat or cold shocking Irradiation of spermatozoa was given for a duration of 1 min and the eggs were fertilized in vitro. Cold shock at a temperature of
3± 1°C for a duration of 30 and 60 min and heat shock at a temperature of 39± 1°C for a duration of 1 and 2 min was applied to induce diploidy. Higher percentage of hatching (68.66) was observed for meiotic gynogens at a shock temperature of 39± 1°C for a duration of 1 min, 5 min after fertilization (af). Higher percentage of mitotic gynogenetic induction (15.33) was observed at a temperature shock of 39± 1°C for a duration of 1 min, 30 min af
Marine fisheries of Karnataka State, India
This contribution provides an overview of the marine capture fisheries off the coast of Karnataka State, India. It covers the main fisheries and fishing gears, production trends (by main species /groups and gears), assessment results and fisheries management. Marine fisheries production in the State increased from about 57,000 t/year during the 1950s to a peak of about 250,000 in 1989, declining to about 150,000 t/year by 1995. Substantive changes have been noted in dominant gears and species groups contributing to the catch between 1980-84 and 1990-95. Results of assessments indicate that many commercially important stocks are overfished, thus requiring a reduction in fishing effort
Fecundity and spawning of the Atlantic horseshoe crab, Limulus polyphemus, in Pleasant Bay, Cape Cod, Massachusetts, USA
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Blackwell for personal use, not for redistribution. The definitive version was published in Marine Ecology 27 (2006): 54-65, doi:10.1111/j.1439-0485.2005.00053.x.This study provided the first comprehensive analysis of Atlantic horseshoe crab (Limulus polyphemus) fecundity. Limulus appear to be determinate spawners, maturing all their eggs for the breeding season before spawning begins. On average, larger females held a larger number of eggs (63,500) than smaller females (14,500). By the end of the breeding season there was an average of 11,600 mature eggs female-1 left undeposited, regardless of female size. Larger females laid a higher percentage of the eggs they contained. Thus they not only contain more eggs, but are more effective at laying them as well. Size of spawning females ranged from about 185-300 mm prosomal width, with by far the highest concentration in the mid-size ranges. Although on an individual basis large females carry and lay the greatest number of eggs, mid-size crabs as a group contributed more to the horseshoe crab population in Pleasant Bay because they were more plentiful (net fecundity was highest for mid-size crabs). These results have implications for the management of this important species, which is harvested for bait, scientific, and biomedical uses. Incorporation of these results into models and other management tools can help predict growth rates, effects of size-selective harvest, reproductive value, and stable stage distribution of populations.This project was partially funded by MIT Sea Grant 8247-5
COVID-19: Rapid antigen detection for SARS-CoV-2 by lateral flow assay: A national systematic evaluation of sensitivity and specificity for mass-testing
Background
Lateral flow device (LFD) viral antigen immunoassays have been developed around the world as diagnostic tests for SARS-CoV-2 infection. They have been proposed to deliver an infrastructure-light, cost-economical solution giving results within half an hour.
Methods
LFDs were initially reviewed by a Department of Health and Social Care team, part of the UK government, from which 64 were selected for further evaluation from 1st August to 15th December 2020. Standardised laboratory evaluations, and for those that met the published criteria, field testing in the Falcon-C19 research study and UK pilots were performed (UK COVID-19 testing centres, hospital, schools, armed forces).
Findings
4/64 LFDs so far have desirable performance characteristics (orient Gene, Deepblue, Abbott and Innova SARS-CoV-2 Antigen Rapid Qualitative Test). All these LFDs have a viral antigen detection of >90% at 100,000 RNA copies/ml. 8951 Innova LFD tests were performed with a kit failure rate of 5.6% (502/8951, 95% CI: 5.1–6.1), false positive rate of 0.32% (22/6954, 95% CI: 0.20–0.48). Viral antigen detection/sensitivity across the sampling cohort when performed by laboratory scientists was 78.8% (156/198, 95% CI 72.4–84.3).
Interpretation
Our results suggest LFDs have promising performance characteristics for mass population testing and can be used to identify infectious positive individuals. The Innova LFD shows good viral antigen detection/sensitivity with excellent specificity, although kit failure rates and the impact of training are potential issues. These results support the expanded evaluation of LFDs, and assessment of greater access to testing on COVID-19 transmission.
Funding
Department of Health and Social Care. University of Oxford. Public Health England Porton Down, Manchester University NHS Foundation Trust, National Institute of Health Research
Introduction: World Healthcare Cooperatives: Challenges and Opportunities
International audienc
World Healthcare Cooperatives: Challenges and Opportunities
International audienceThe healthcare industry is one of the largest and fastest-growing service industries in the world. The respective merits of public and private healthcare systems are continually debated, but a third system - that of healthcare cooperatives - is rapidly emerging as a universal, community-focused and cost-effective alternative. Rooted in remarkable examples from every corner of the world, World Healthcare Cooperatives highlights both the challenges a successful healthcare cooperative may face, as well as its proven effectiveness in making a difference. Understanding that, for many, especially in developing countries, private hospitals and healthcare insurance plans are expensive and out of reach, and that globally many public healthcare systems are under-resourced, chapters demonstrate how healthcare cooperatives have a critical role to play in providing services sustainably and at an affordable cost. Addressing the persistent gap between supply and demand in the healthcare sector, the authors highlight the capability of healthcare cooperatives to create a positive impact. With examples from Canada, Argentina, Japan, Africa, Brazil, Columbia, Sri Lanka, Spain, and India, chapters showcase the services that cooperatives can offer their communities, including the establishment of hospitals, medical facilities, and other infrastructure, as well as opportunities in biotechnology and information technology research. Considering more than 100 million households worldwide that have benefitted from healthcare cooperatives, this pioneering collection triggers a new direction of research to support those seeking to establish healthcare infrastructure in developing and least developed countries in achieving universal healthcare for all. © 2024 K.K. Tripathy, Sneha Kumari, V.G. Venkatesh,All rights reserved. R. Jayalakshmi and M.P. Sukumaran Nair
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Not AvailableIndia is bestowed with a number of locally important cultivable brackishwater finfish species such as Asian seabass, Milkfish, Grey mullet, Pearlspot, Scat, Estuarine grouper, and Cobia, suitable for Brackishwater aquaculture. Diversification assumes significant importance in coastal aquaculture in India as presently, it mostly is limited to shrimp aquaculture alone. The tidal amplitude of the Gujarat coast is higher than other parts of the West Coast. This natural phenomenon had created vast stretches of marshy and saline lands all along the coast. The estimated brackishwater area in Gujarat is around 3,76,000 hectares with the potential area suitable for brackishwater aquaculture being about 83,340 hectares. Navsari District of Gujarat is blessed with abundant potential brackishwater resources which can be utilized for aquaculture for livelihood of coastal communities.Not Availabl
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Not AvailableNot AvailableInclusion of sustained-release androgen-gonadotrophin releasing hormone analogue implants into fertility
treatment regimes of male and female milkfish has been proposed to benefit artificial maturation outcomes. This
study aimed to investigate scope of co-administration of the androgen, 17α –methyl testosterone (17 α -MT) in
combination with GnRHa as a single hormone pellet at varied frequencies in male and female milkfish to affect
maturation, egg quality, spawning and subsequent larval fitness. Cholesterol pellet combined with GnRHa and 17
α–MT in equal amount was found superior to individual treatment in breeding responses (Experiment-1, 2015).
In second experiment during 2016–2019 we evaluated effectiveness of chronic (10 implantations/year-
December, January–September) and assisted (04 implantation/year- Dec, Jan, April, July) implantation of
combined hormone pellet to compare breeding responses during trimester of implantation/breeding period
divided as early (January–March), maximum (April–June) and extended (July–September) phase. Assisted
hormone implantation helped to achieve desired percentage of unimodal distribution of mature oocytes
(650–750 μm) reaching final oocyte maturation (FOM) stage in milkfish along with higher spawning frequency.
On the contrary, chronic implantation caused an increased percentage of vitellogenic oocytes with bimodal
distribution (250–500 μm and 500–600 μm) in ovary with reduced spawning events. Application of combined
hormone implants, both assisted and chronic facilitated sustained release of both gonadotropin releasing hor-
mone analogue (GnRHa) and androgen (17 α – MT) together and thereby induced entire reproductive axis
resulting in extended spawning frequency for seven months (February–September). We also observed that
milkfish breeding was aligned with abiotic factors such as higher water temperature and salinity along with
synchrony to full moon or new moon. We conclude that assisted type of implantation pattern significantly
improved maturation, milting male %, average fecundity, egg diameter, fertilization rate, hatching rate and
larval length compared to that of chronic implantation with added benefit of reduced handling stress. This study
represents the first report of milkfish captive maturation and hatchery seed production in tropical climate using
combined hormone pellet administration.ICAR-CIB