Musammilu, K K; Dr.Gopalakrishnan, A(National Bureau of Fish Genetic Resources Cochin Unit, Central Marine Fisheries Research Institute, April , 2008)
[+]
[-]
Abstract:
The family Cyprinidae is the largest of freshwater fishes and, with the possible
exception of Gobiidae, the largest family of vertebrates.Various members of this family are important as food
fish, as aquarium fish, and in biological research. In this study, a fish species from this family exclusively found in the west flowing rivers originating from the Western Ghat region — Gonoproktopterus curmuca — was
taken for population genetic analysis.There was an urgent need for restoration ecology by the development of apt management strategies to exploit resources judiciously. One
of the strategies thus developed for the scientific management of these resources was to identify the natural units of the fishery resources under exploitation
(Altukov, 1981). These natural units of a species can otherwise be called as stocks. A stock can be defined as a panmictic population of related individuals within a single species that is genetically distinct
from other such populations.It is believed that a
species may undergo micro evolutionary process and differentiate into
genetically distinct sub-populations or stocks in course of time, if reproductively
and geographically isolated.In recent times, there has been a wide spread degradation of natural aquatic environment due to anthropogenic activities and
this has resulted in the decline and even extinction of some fish species. In such situations, evaluation of the genetic diversity of fish resources assumes important to
conservation.The species selected for the study, was short-listed as one of the candidates for stock-specific, propagation assisted rehabilitation and
management programme in rivers where it is naturally distributed. In connection
with this, captive breeding and milt cryopreservation techniques of the species have been developed by the National Bureau of Fish Genetic Resources, Lucknow. However, for a scientific stock-specific rehabilitation
programme, information on the stock structure and basic genetic profile of the
species are essential and that is not available in case of G. curmuca. So the present work was taken up to identify molecular genetic markers like allozymes, microsatellites and RAPDs and, to use these markers to discriminate the distinct populations of
the species, if any, in areas of its natural distribution. The genetic markers were found to be powerful tools to analyze the population genetic
structure of the red-tailed barb and demonstrated clear cut genetic differentiation between pairs of populations examined. Geographic isolation by land distance is likely to be the factor that contributed to the restricted gene flow between the river systems. So the present study emphasizes the need for stock-wise, propagation
assisted-rehabilitation of the natural populations of red-tailed barb,
Gonoprokfopterus curmuca.
Abdul Muneer, P M; Gopalakrishnan, A(National bureau of fish genetic resources cochin unit, 2005)
[+]
[-]
Abstract:
The present study Molecular genetic characterization of endemic yellow catfish ,generated an important information on the genetic variation and stock structure of the endangered yellow catfish(Horabagrus brachysoma) endemic to the western Ghats. Three genetically discrete stocks of the species have been identified for the first time using allozymes, RAPD(Random Amplified Polymorphic DNA) and microsatelite markers and it is a significant step towards realizing the goal of management of fishery and conservation of the yellow catfish populations in the rivers of the Western Ghats region. In conclusion genetic markers were found to be powerful tools to analyze the population genetic structure of the yellow catfish. Geographic isolation by land distance,inbreading as a result of over-exploitation etc are some reasons for the genetic differenciation between the pairs and deficiency of hetrozygosity revealed by the two co dominant markers, allozyme, and microsatelites.the study emphasizes the need for stock-wise, propagation assisted-rehabilitation of the natural populations yellow catfish
Anju Antony, Moonjely; Thomas, P C(Cochin University of Science and Technology, August 25, 2014)
[+]
[-]
Abstract:
There are a number of genes involved in the regulation of functional process in marine bivalves. In the case of pearl oyster, some of these genes have major role
in the immune/defence function and biomineralization process involved in the pearl formation in them. As secondary filter feeders, pearl oysters are exposed to various kinds of stressors like bacteria, viruses, pesticides, industrial wastes, toxic metals and petroleum derivatives, making susceptible to diseases. Environmental changes and ambient stress also affect non-specific immunity, making the organisms vulnerable to infections. These stressors can trigger various cellular responses in the animals in their efforts to counteract the ill effects of the stress on them. These include the expression of defence related genes which encode factors such as antioxidant genes, pattern recognition receptor proteins etc. One of the strategies to combat these problems is to get insight into the disease resistance genes, and use them for disease control and health management. Similarly, although it is known that formation of pearl in molluscs is mediated by specialized proteins which are in turn regulated by specific genes encoding them, there is a paucity of sufficient information on these genes.In view of the above facts, studies on the defence related and pearl forming genes of the pearl oyster assumes importance from the point of view of both sustainable fishery management and aquaculture. At present, there is total lack of sufficient knowledge on the functional genes and their expressions in the Indian pearl oyster Pinctada fucata. Hence this work was taken up to identify and characterize the defence related and pearl forming genes, and study their expression through molecular means, in the Indian pearl oyster Pinctada fucata which are economically important for aquaculture at the southeast coast of India. The present study has successfully carried out the molecular identification, characterization and expression analysis of defence related antioxidant enzyme genes and pattern recognition proteins genes which play vital role in the defence against biotic and abiotic stressors. Antioxidant enzyme genes viz., Cu/Zn superoxide dismutase (Cu/Zn SOD), glutathione peroxidise (GPX) and glutathione-S-transferase (GST) were studied. Concerted approaches using the various molecular tools like polymerase chain reaction (PCR), random amplification of cDNA ends (RACE), molecular cloning and sequencing have resulted in the identification and characterization of full length sequences (924 bp) of the Cu/Zn SOD, most important antioxidant enzyme gene. BLAST search in NCBI confirmed the identity of the gene as Cu/Zn SOD. The presence of the characteristic amino acid sequences such as copper/zinc binding residues, family signature sequences and signal peptides were found out. Multiple sequence alignment comparison and phylogenetic analysis of the nucleotide and amino acid sequences using bioinformatics tools like BioEdit,MEGA etc revealed that the sequences were found to contain regions of diversity as well as homogeneity. Close evolutionary relationship between P. fucata and other aquatic invertebrates was revealed from the phylogenetic tree constructed using SOD
amino acid sequence of P. fucata and other invertebrates as well as vertebrates
Silpa., B.L; Dr. Reji Srinivas(Cochin University of Science and Technology, September 11, 2015)
[+]
[-]
Abstract:
Earth’s coastline defines the interface between land and water.
Although the area they cover is insignificant, their linear extent is
enormous and the variety of landforms they evolve over earth’s surface
is remarkable. Over one third of the world’s population lives either at the
coasts or in adjacent coastal low land areas. The coast is a zone of
intense energy input. This energy transported by waves, arrives at the
coast and is available for work. The result is that the processes of
sediment transport are set in motion – processes that cause
morphological change. Thus the coasts are the most rapidly changing
places on earth's surface and they play an important role in global
transportation of sediments and hence studies on the coastal zone
where air, land and water interact is a focus of particular interest among
the scientific community. The coastal areas across the world are also of
extreme economic importance as they contain abundant natural
resources and favorite tourist destinations because of their highly scenic
landscape
Sree Remya, T. S.; Dr. Swapankumar Ghosh(Cochin University of Science and Technology, February 12, 2015)
[+]
[-]
Abstract:
The prospective impact of nanomaterials in science and technology has followed an
increasing trend due to their unique chemical and physical properties compared to bulk.
Significant advances in current technologies in areas such as clean energy production,
electronics, medicine, and environment have fuelled major research and development
efforts in nanotechnology around the world. This leads to the opportunity to use such
nanostructured materials in novel applications and devices. Ceria, zirconia, alumina and
titania are some of the major oxides which find vast applications as a nanomaterial on a
wider side.
Joice, Thomas V; Dr.Madhusoodana,Kurup B(Cochin University Of Science And Technology, September , 2003)
[+]
[-]
Abstract:
Mechanized fishing started in Indian waters in mid —fifties and large-scale
operation of trawl fishing began in the mid sixties by the surfeit of individual
entrepreneurs. The southwest coast of India especially the coastal waters of
Kerala are the most productive area in the subcontinent and the state has been
in the forefront in marine fish production (Kurup, 2001a). Though the coastline
of Kerala is one tenth of the coastline of India, the state occupies the foremost
position in the marine fish production of the country, accounting for more than
30% of the marine fish landings (Thomas, 2000). The coastal waters of Kerala
have rich and diversified fishery resources, which are prone to heavy
exploitation by a unprecedently high number of fishing gears, among them,
mechanized bottom trawlers with a numerical strength of 4550 (Kurup, 2001a)
against the permissible number of 1145 (Kalawar, et al., 1985) are the most
destructive. Trawling operations during monsoon periods in Kerala has been a
subject of controversy between traditional fishermen and trawl fishers on a
subject that trawl fishing destroys large amount of juveniles and young ones of
fishes since this period is the major breeding season of most of the fish and
prawns (John, 1996). Therefore Government of Kerala imposed a ban on
bottom trawling activities from 1988 onwards for a period varying from 21-70
days, which usually commences from June 15th. Though many studies
revealed that large amount of non-target groups were destroyed in the
commercial trawl fishing in the Indian waters, no concerted study has been
conducted so far to evaluate the real impact of bottom trawling on the sea
bottom and its living communities. The present study was conducted to assess
the impact of excessive bottom trawling exerted on the sea bottom habitat and
its living communities, which would be useful in impressing up on the
seriousness of habitat degradation and biotic devastation, enabling the
concerned to adopt relevant conservation and management steps to conserve
the resources for sustainable exploitation
Description:
School of Industrial Fisheries
Cochin University of Science and Technology
Joshi, K K; Dr.Parameswaran Pillai, P(Cochin University Of Science And Technology, November , 1990)
[+]
[-]
Abstract:
The present work "Nature and Ecological Significance of Nutrient
Regeneration in different Prawn Culture Fields" was undertaken to understand
the seasonal variation of nutrients, nutrient cycling and primary productivity
of the prawn culture systems. The main emphasis was to find the qualitative
and quantitative estimates of distribution of total phosphorus, inorganic
phosphorus, organic phosphorus, total nitrogen and nitrogen fractions in the
water. The effect of nutrient cycling on primary productivity and concentration
of metals also form one part of the study.
The entire thesis comprise of only one major chapter with subchapters
such as, Introduction (I), Review of Literature (2), Material and
Methods (3), Results (14), Discussion (5), Executive Summary (6) and Biblio~
graphy (7)
Description:
Centre of Advanced Studies in Mariculture,Cochin University Of Science And Technology
Praveen, S S; Dr.Kurian, N P(Cochin University of Science and Technology, May 25, 2012)
[+]
[-]
Abstract:
Tsunamis are water waves generated by a sudden vertical displacement of the water surface. They are waves generated in the ocean by the disturbance associated with seismic activity, under sea volcanic eruptions, submarine landslides, nuclear explosion or meteorite impacts with the ocean. These waves are generated in the ocean and travel into coastal bays, gulfs, estuaries and rivers. These waves travel as gravity waves with a velocity dependent on water depth. The term tsunami is Japanese and means harbour (tsu) and wave (nami). It has been named so because such waves often develop resonant phenomena in harbours after offshore earthquakes.
Description:
Centre for Earth Science Studies, Thiruvananthapuram
Vijay,John Gerson; Jacob,Chacko; K K C Nair(National Institute of Oceanography & CUSAT, August , 2005)
[+]
[-]
Abstract:
The present work aims at deciphering the processes that control the nutrient distribution along the EEZ (Exclusive Economic Zone of India) of the west coast of India and to bring out its linkage with primary and secondary productivity. This work assume utmost importance as very few studies have hitherto focused entirely on the EEZ of the west coast of India to address the biochemical responses brought about by monsoons. The present study examines the seasonal variations in physicochemical parameters and associated primary biological responses along the west coast of India. This study targets to measure and understand the shelf ocean exchange in a typical coastal upwelling region of the southeast Arabian Sea, and the influence of convective mixing along the northern part of the west coast of India. The study focuses more directly on coastal upwelling along the southwest coast of India, within the EEZ. The effects of coastal upwelling, eddy formation and the offshore advection are apparent in the present investigation. This has consequences to fisheries and climate, in energy transfer to the food chain and the increased sequestering of carbon in the ocean. The study also focuses on the Oxygen Minimum Zone (OMZ) and dentrification observed along the EEZ of the west coast of India on a seasonal scale. In the study, an attempt is also made to demarcate the geographical boundaries of the denitrification zone in the EEZ of India and on the nature and magnitude of these variations, on a seasonal and inter annual scales
Padma, P; Dr.Muraleedharan Nair, S(Cochin University of Science & Technology, October , 2008)
[+]
[-]
Abstract:
This study was aimed at to characterize the spatio-temporal trends in
the distributional characteristics of various species of nitrogen and phosphorus as
well as to elucidate the factors and processes aflecting these nutrients in the
dissolved, particulate and sedimentary phases of a river estuarine system. The
main area of study is Chalakudy river in Kerala, which is a fresh water system
originating from Anamalai hills and ending at Arabian Sea. Its basin is between
I00 05 ’ to I00 35’ North latitude and 76” 15 ’ to 760 55’ East longitude. Being a
riparian bufler zone, the dynamics of nutrient mobility tend to be more complex
and variable in this river-estuarine system.The diflerent species of nitrogen estimated from the filtrate were nitrite-N, nitrateN,
ammonia-N, urea-N, total nitrogen and residual nitrogen. The diflerent forms
of phosphorus estimated from the filtrate were phosphate-P, total-P and residualP.
Pre weighed sediments as well as particulate matter were analysed for
quantijying nitrite-N, nitrate-N, ammonia-N and urea-N. Total nitrogen was estimated after digestion with potassium persulfate. Fractionation of phosphorus
in sediment/particulate matter was performed by applying sequential extraction
procedure. The dijferent forms of phosphorus thus estimated were loosely bound
(exchangeable) P, Fe/Al bound P, polyphosphates, Ca bound P and refractory P.
Sedimental total P was also measured directly by applying digestion method.The analyses carried out in this bimonthly annual survey have revealed specific
information on the latent factors influencing the water quality pattern ofthe river.
There was dependence among the chemical components of the river sediment and
suspended matter, reflecting the water quality. A period of profound
environmental change occurred and changes in various species had been noted in
association with seasonal variations in the waterway, especially following
enhanced river runoff during the monsoon. The results also successfully
represented the distribution trend of nutrients during the rainy as well as dry
season. Thus, the information gathered in this work will also be beneficial for
those interested or involved in river management, conservation, regulation and
policy making in regional and national levels.
Description:
Dept.of Chemical Oceanography,Cochin University of Science and Technology.
Kiron, Viswanath; Dr. Paul, Raj R(Cochin University of Science and Technology, May , 1989)
[+]
[-]
Abstract:
Most tropical aquatic environments are naturally
fertile and their natural fertility is renewed very rapidly. Natural food for many cultivable organisms can be grown to the maximum by proper management. However, enrichment of the environment can be done through rational fertilization. Still further increase in stocking rates, can yield increased crop if adequate feeding is done. Thus fish and shellfish nutrition is an important aspect of the multidisciplinary subject of aquaculture. The oldest and most classical studies in physiology have investigated the nutritional needs of the species of interest to aquaculture. The alimentary requirements for
proteins, lipids, mineral salts and vitamins have been established for some temperate species. But, the nutritional requirements of only few tropical species have been studied. Before formulating a diet, a thorough knowledge of the nutrient requirement of the species is essential. It is against this background that the present area of investigation has been identified. "Nutritional requirements of the fry of gold-spot mullet Liza parsia" is a comprehensive attempt to quantify the nutritional factors that are essential for producing healthy fingerlings for stocking the farms. Aspects such as the protein and lipid requirements of the fry, the vitamin essentiality, nutritive evaluation of protein and lipid sources suitable for compounding diets were covered in this research project. The ultimate aim has been to evolve practical diets which could be applied in the nursery phase for juvenile production.