Philip, Samuel P; Dr.George, M J(Cochin University Of Science And Technology, November , 1987)
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Abstract:
‘Biochemical genetics of selected commercially important
penaeid prawns‘ dloted was carried out by collecting
samples from different important fishing ceatres of India
and the practical work was carried out in the Research
Centre of CMFRI laboratories attached with those places.
On the whole, in crustacea little importance has been
given so far in finding out tin genetic characteristics of
different species, genetic variation within and between
species and ontogenetic variations in lobsters, prawns and
other crustaceans. Prawn is caunercially important group
where very little attention had been given so far to find
out the racial divergence which may exist in cufferent
species. with the increased foreign exchange earning and
consequent indiscriminate over exploitation of existing
resources of prawns resulting in depletion of the marine
rescurces, alternative ways and augmenting production has
become essential. In this connection genetic manipulation
of the broodstock will surely bring about the heterogenous
characters to multiply production. In order to understand
racial fragmentation of sane of the coumercially important
prawns such as Pengeus ggdicus and Parggenagsis sgliferg
the isozyme studies were carried out. Qatogenetic variation
of g. indicus showed stage specific electrophoretic variation.
Inter species variation studies was carried out for the
closely aligned Penaeus species
Description:
Department Of Marine Sciences,Cochin University Of Science And Technology
Ambili, V; Narayana, A C(Cochin University of Science and Technology, October , 2010)
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Abstract:
Drainage basins are durable geomorphic features that provide insights into the long term evolution of the landscape. River basin geometry develop response to the nature and distribution of uplift and subsidence, the spatial arrangement of lineaments (faults and joints), the relative resistance of different rock types and to climatically influenced hydrological parameters . For developing a drainage basin evolution history, it is necessary to understand physiography, drainage patterns, geomorphic features and its structural control and erosion status. The present study records evidences for active tectonic activities which were found to be responsible for the present day geomorphic set up of the study area since the Western Ghat evolution. A model was developed to explain the evolution of Chaliar River drainage basin based on detailed interpretation of morphometry and genesis of landforms with special emphasis on tectonic geomorphic indices and markers.
Description:
Department of Marine Geology and Geophysics, Cochin University of Science and Technology
The length – weight relationship and relative condition factor of the shovel nose catfish, Arius subrostratus (Valenciennes,
1840) from Champakkara backwater were studied by examination of 392 specimens collected during June to September
2008. These fishes ranged from 6 to 29 cm in total length and 5.6 to 218 g in weight. The relation between the total length and
weight of Arius subrostratus is described as Log W = -1.530+2.6224 log L for males, Log W = - 2.131 + 3.0914 log L for
females and Log W = - 1.742 + 2.8067 log L for sexes combined. The mean relative condition factor (Kn) values ranged from
0.75 to 1.07 for males, 0.944 to 1.407 for females and 0.96 to 1.196 for combined sexes. The length-weight relationship and
relative condition factor showed that the well-being of A. subrostratus is good. The morphometric measurements of various
body parts and meristic counts were recorded. The morphometric measurements were found to be non-linear and there is no
significant difference observed between the two sexes. From the present investigation, the fin formula can be written as
D: I, 7; P: I, 12; A: 17 – 20; C: 26 – 32. There is no change in meristic counts with the increase in body length.