Suresh, K; Dr.Mohandas, A(Cochin University of Science And Technology, January , 1988)
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Abstract:
It is well known that under certain conditions, populations of oysters
and clams are susceptible to destructive epizootics caused by pathogenic
micro-organisms. It has also been shown that exposure of mammals to certain
heavy metals causes increased susceptibility to and severity of microbial
infections (Koller, 1980). Consequently, pollutants that affect haemocyte
viability or interfere with internal defence functions of the haemocytes which
are considered as the major means of defence in moliuscs against invading
foreign organisms and pathogens (Cheng, 1981) may have profound effect on
long term survival of molluscan populations. All these justify the significance
of the present study in the context of the current status on molluscan
culture programme, and how the data on molluscan haematological studies
.could be taken as the reliable criteria for pollution monitoring studies.
Description:
School of Marine Sciences, Cochin University of Science and Technology
Jose,Jacob P; Dr.Ravindranatha Menon,N(Cochin University of Science and Technology, February , 1988)
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Abstract:
In recent years, pollution in general and sea water pollution in particular, has become an important topic for national and international considerations. Because of its impact on society, marine pollution has attracted great attention from politicians, administrators, natural scientists and technologists all over the world. To save our environment from further deterioration, it is essential to have an assessment of this problem This thesis involves investigation of the lethal and sub lethal effects of four pesticides and two petroleum oil, individually and in combinations on two commercially important bivalves. Among the four pesticides used two are organophosphates and the other two are organochlorines. Synthetic Pesticides, especially organophosphates and organochlorines have become increasingly important additions to chemical wastes polluting natural aquatic Communities special attention is given in the present investigation to delineate the combined toxic effect of oil and pesticides. The results are presented under different sections to make the presentation meaningful.
Description:
Division of Marine Biology,Microbiology and Biochemistry;
School of Marine Sciences; Cochin University of Science and Technology
Kesavan Nair, A K; Dr.Alagaraja, K(Cochin University Of Science And Technology, June 24, 1988)
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Abstract:
The preceding discussion and review of literature show
that studies on gear selectivity have received great
attention, while gear efficiency studies do not seem to have
received equal consideration. In temperate waters, fishing
industry is well organised and relatively large and well
equipped vessels and gear are used for commercial fishing
and the number of species are less; whereas in tropics
particularly in India, small scale fishery dominates the
scene and the fishery is multispecies operated upon by
nmltigear. Therefore many of the problems faced in India
may not exist in developed countries. Perhaps this would
be the reason for the paucity of literature on the problems
in estimation of relative efficiency. Much work has been
carried out in estimating relative efficiency (Pycha, 1962;
Pope, 1963; Gulland, 1967; Dickson, 1971 and Collins, 1979).
The main subject of interest in the present thesis is an
investigation into the problems in the comparison of fishing
gears. especially in using classical test procedures with
special reference to the prevailing fishing practices (that
is. with reference to the catch data generated by the
existing system). This has been taken up with a view to
standardizing an approach for comparing the efficiency of
fishing gear. Besides this, the implications of the terms
‘gear efficiency‘ and ‘gear selectivity‘ have been examined
and based on the commonly used selectivity model (Holt,
1963), estimation of the ratio of fishing power of two gear
has been considered. An attempt to determine the size of
fish for which a gear is most efficient.has also been made.
The work has been presented in eight chapters
Description:
Central Institute Of Fisheries Technology,Cochin University Of Science And Technology
Sajan,K; Dr.Damodaran, K T(Cochin University of Science And Technology, August , 1988)
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Abstract:
This study enfolds the environment of
deposition and the lateral variation in texture,
mineralogy and geochemistry of the Ashtamudy lake
sediments. While the heavy mineral and clay mineral
investigations enable us to decipher the nature, texture
and source of sediments; organic matter and carbonate
contents and the geochemical analysis of major and minor
elements help establish the distribution and
concentration of the same in regard to the various
physico-chemical processes operating in the lake.
Study of trace elements holds prime importance in
this work, since their concentrations can be used to
outline the extent of contaminated bottom area, as well as
the source and dispersal paths of discharged_pollutants.
In short, this study brings out a vivid picture of the
mineralogy and geochemistry of the lake sediments
in different environments, viz., the freshwater, brackish
water and marine environments that are confined to
the eastern, central and western parts of the lake
respectively. For the better understanding and
expression of the results of the analysis, the lake
has been divided into 3 zones namely: eastern part,
central part and western part.
Description:
School of Marine sciences, Cochin University of Science And Technology
Joseph,K J; Dr.Ramachandran Nair,P V(Cochin University Of Science And Technology, August , 1988)
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Abstract:
The present study is concentrated on a composite group of algae of phy—
toplankton. The algae in the aquatic environment are the most important of
all ch1orophy1l- bearing life on earth on which considerable attention is being
given on account of their supreme status in the aquatic food chain. Though the
higher plants serve as the major primary producers in the terrestrial biocycle,
the primary producers in the aquatic ecosystem especially in the marine environment-" assume unparalleled significance ‘because of their c'ontribution.to the
high magnitude of production generating the fishery resources
Description:
Division Of Marine Biology, Microbiology And Biochemistry
School Of Marine Sciences,Cochin University Of Science And Technology
Jalajakumar,V S; Dr.Kuttyamma, V J(Cochin University of Science And Technology, August , 1988)
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Abstract:
In order to check the damage caused by the parasites, even though it is difficult in open waters, a proper understanding of the seasonal variation in the distribution of the parasite and other factors like age of the host, sex of the host, which affect distribution of parasite is a must. Although several workers have carried out investigations on the taxonomy of metazoan parasites of marine and brackish water Fishes of India, very little attempt is made to correlate such investigations with the host and the environment. In this thesis such an attempt is made by the researcher.
In chapter one the literature related to the prevalence, mean intensity of infection, and histopathological changes caused by the metazoan parasites, in particular by helminths, copepods and isopods, was reviewed. Chapter two contains observations on the distribution pattern of parasites in relation to the season, sex, and size of the host. It was found that the prevalence rate of radiorynchus_indicus infecting the alimentary canal of Tachysurugs mgacuglatus, Ergasilus sp. infecting the gills of T maculatus, and Lernaeeniicus ramosus found on the body surface of Qeimgipteirfugs jagonicus was higher during monsoon season. But agarna malayi found in the opercular chamber and Ehilometra cephalus infecting the gonads of valamugil speiglari showed a higher prevalence rate during the postmonsoon season. This was discussed on the basis of the hydrographical characteristics prevailing in the study area during the three different seasons.
It was also observed that the sex of the host did not influence significantly the distribution pattern of the parasites. The reasons for this were also discussed. Invariably, the size of the host
was found to influence the parasite distribution pattern. It was observed that the prevalence rate showed an increase with increase in size of the fish. This was discussed on the basis of food habits of the host, along with other aspects An attempt was made in chapter three to study the histopathological effects of‘ the various parasites on their respective sites of attachments on host Fishes. It was found that except Rhadinorhyhchugs indicus, all other parasites produced damages of varying intensity, in the form of hypertrophy, rhyperplasia, haemorrhage, tissue disruption and ulcers. Interestingly, E. indicus, an acantho— cephalid with a powerful proboscis for attachment was found not to cause any serious damage to the intestine of the host Fish. All these aspects are included in the third and final chapter of the thesis.
Description:
School of marine sciences, Cochin University of Science And Technology
Ramachandran, A; Dr.Ranganathan, N(Cochin University of Science And Technology, September , 1988)
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Abstract:
Kerala was the pioneer in modern seafood processing and
exporting. But now the industry is Iacingalot of problems due to
low productivity and deterioration in the quality of the products.
only about 17% of the installed freezing capacity in sea food
processing industry was reported to be utilised during 1979-80.
The price of the export commodities its decided by the buyers
based on international supply and demand pattern and based on
the strength and weakness of dollar/yen. The only way to increase
the profitability of the processors is to reduce the cost of
production to the possible extent. The individual processors
find it difficult to continue in this field due to low productivity
and quality problems.
The main objectives of the research are to find out how
the production is being managed in the seafood processing(freezing) 17industry
in Kerala and the reasons for low productivity and
poor quality of the products. The study includes a detailed
analysis of Location of the factories. Layout Purchase, production and storage patterns. Production planning and scheduling. Work Measurement of the processing of important products. Quality Control and Inspection. Management Information System
Description:
Department of Industrial fisheries, Cochin University of Science And Technology