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Subject: Fisheries × End date: 2002 × Type: Thesis × Thesis Type: M.Sc ×
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Now showing 1 - 9 of 21
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    ThesisItemOpen Access
    Utilization of prawn waste as pig feed
    (Department of Animal Nutrition, College of Veterinary and Animal Sciences, Mannuthy, 1991) Syam, Mohan K M; KAU; Sivaraman, E
    An investigation was carried out to assess the feeding value of prawn waste as a partial or complete replacement of unsalted dried fish in the rations for growing – finishing pigs. Thirty – two Large White Yorkshire weanling pigs with an average body weight of 9.1 kg were distributed randomly and uniformly as far as possible to four groups (Groups 1, 11, 111 and IV) of eight animals each, with regard to age, sex and body weight and housed in pairs of the same sex. The four dietary treatments A, B, C and D were allotted to the pigs in the groups 1, 11, 111 and IV respectively. Of the total protein, 25 per cent in the diets A, B and C and 12.5 per cent in the diet D were provided as animal protein. Unsalted dried fish was used as animal protein source in the diets C and D. Diet C formed the control diet. In the diets A and B, 50 per cent and 100 per cent replacements respectively of animal protein from unsalted dried fish were made using dried prawn waste. All the animals were maintained on the respective diets with 18 per cent total protein upto an average live weight of 50 kg and with 14 per cent protein till they attained a body weight of 70 kg or 8 months of age, whichever was earlier, when they were slaughtered to study carcass characteristics.
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    ThesisItemOpen Access
    Development of Malaysian Type Fish Crackers From Nemipterus Japonicus (BLOCH)
    (Department of Processing Technology,College of Fisheries, Panangad, 2001) Venugopal, Dubakula; KAU; Sajan, George
    A study was undertaken for the preparation of fish crackers using a low cost fish, threadfm bream (Nemipterus japonicus, Bloch). A method was standardised for making crackers based on that generally followed in Malaysia. Fish meat was mixed with various food additives such as starch, salt, sugar, monosodium glutamate, colour and water, and stuffed into high-density polyethylene casings as rolls, cooked, cooled, sliced and dried.
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    ThesisItemOpen Access
    Studies on the electrophoretic pattern of Fish/ Shellfish proteins subjected to frozen storage
    (Department of Processing Technology,College of Fisheries, Panangad, 2000) Bomy, Chummar; KAU; Nambudiri, D D
    Freezing considered as an excellent process for preserving the quality of fish for longer periods. But freezing may affect various flesh components, especially the proteins. Sarcoplasmic proteins play a major role in species identification of fish and fishery products. While myofibrillar proteins play a major role in the jellying properties of surimi and surimi based products. The changes to these groups of proteins due to freezing and frozen storage have received much attention. Four species Megalaspis cordyla, Labeo rohita, Penaeus indicus and Parapenaeopsis styli/era were used for the frozen storage study. Samples were stored for 90 days at -18°C and samples were collected at 15 day. intervals and Salt Soluble Nitrogen (SSN), Water Soluble Nitrogen (WSN) and Non-Protein Nitrogen (NPN) content were determined. Electrophoretic pattern of both Salt Soluble Proteins (SSP) and Water Soluble Proteins (WSP) of frozen stored sample were compared with that of the fresh sample.
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    ThesisItemOpen Access
    High density rearing of Labeo Rohita (Hamilton) spown indoors using different feeds
    (Department of Aquaculture, College of Fisheries, Panangad, 1998) Dinesh, K; KAU; Mohankumaran, Nair C
    Three day old rohu spawn was reared in indoor tanks with eight different feeds The diets tried were newly hatched Artemia nauplii, size graded Moina micrura, formulated feed, Artemia nauplii + formulated feed, Moina micura+ formulated feed, first 3 days Artemia nauplii and formulated feed later on, first 3 days Moina micrura and formulated feed later on and mixed zooplankton + ricebran and GOC in I: I ratio (conventional method).
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    ThesisItemOpen Access
    Impact of training programme on hygienic measures followed in pelling sheds
    (Department of Management Studies, College of Fisheries, Panangad, 1989) Daisy, C Kappen; KAU; Pushkaran, P S
    The study was conducted in Quilon district of Kerala with a view to measure the impact of training programme on hygienic measures followed in peeling sheds. The major objectives were: 1. To study the level of knowledge about hygienic measuroe of trained peeling shed workers in comparison with those who have not attended the training programme. 2. To study the perception of the trained peeling shed workers about the quality of the product. • 3. To compare the association, if any, existing between the socio-psychological and economic factors of trained and untrained peeling shed workers with the level of knowledge and extent of perception. 4. To study the motivational factors responsible for attending the training programme by the peeling shed workers. The sample consisted of randomly selected 60 trained and 60 untrained peeling shed workers. Data were collected using interview schedule and suitable statistical techniques were employed for the analysis of data. The study revealed that the trained peeling shed workers had significantly higher knowledge than untrained peeling shed workers. They also had significantly higher perception about the quality of the product than untrained peeling shed workers. The peeling shed workers perceived the factor ‘Quality of the raw material’ as the most important one in determining the final quality of the product. The perception on the factors contributing to the final quality of the product were same for both trained and untrained peeling shed workers. The selected independent variables together contributed significantly in the variation in knowledge and perception about the quality of the product of both trained and untrained peeling shed workers. The correlation analysis revealed that education was positively and significantly related with level of knowledge of trained peeling shed workers; while age, occupation and family indicated negative and significant association. In the case of untrained peeling shed workers extension orienta¬tion is the only variable Which Indicated positive and signi¬ficant relationship with level of knowledge. Education showed positive and significant relationship with perception about the quality of the product of trained peeling shed workers. Age and occupation revealed negative and significant association. In the case of untrained peeling shed workers only age Indicated negative and significant relationship with perception about the quality of the product. Innovativeness was the major motive which induced the peeling shed workers to attend the training programme.
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    ThesisItemOpen Access
    Studies on depuration of edible oyster Crassostrea madrasensis (Preston)
    (Department of processing technology, College of fisheries, Panangad, 1993) Usha, P T; KAU; Damodaran, Namboodiri
    Oysters crassostrea madrasensis harvested from cochin back waters are commonly contaminated with low levels of food poisoning organisms such as E.coli, Salmonella, Shigella, Vibrio cholera, V-parahaemolyticus etc, heavy metals like cadmium, lead, copper, zinc, mercury etc and sand content. Depuration studies were conducted to find out any changes in the biochemical constituents such as total Nitrogen, salt soluble Nitrogen, Non protein Nitrogen, Ash and sand content. The studies revealed that there were no significant changes in the biochemical constituents during the 48th depuration period. Oysters were laboratory contaminated to levels in excess of 10000 cells /g with E.coli and it was cleansed from such oysters during purification in a laboratory depuration unit that used ultraviolet light and chlorination for sterilizing the depuration water. Depuration in sterilized water using ultra violet light treatment was found to be more efficient in cleansing the oyster of pathogen, E.Coli than using chlorination. Of the two salinity tested depuration of oyster in seawater at 35 ppt salinity gave better results compared t that in 30ppt salinity sea water both sterilised with uv light. Depuration of oyster in unsterile seawater and in seawater sterilised 10 ppm chlorination was found to be least effective in cleansing the oyster to the acceptable international standard of less than 2.3 E.Coli/g oyster meat within 48h depuration. There was no appreciated change in the sensory characteristics of oysters such as aroma, taste, and flavor. However there was significant change in the grittiness characteristics of oyster after 48h depuration. Depuration was not effective in removing heavy metals such as cadmium, lead, zinc, Tin and Mercury from the oyster within the depuration period of 48h.
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    ThesisItemOpen Access
    Breeding biology of Villorita cyprinoides (Gray) in relation to salinity gradients
    (Department of Fishery Biology, College of Fisheries, Panangad, 1991) Sudha, B Nair; KAU; Jose, T M
    The present study was undertaken to investigate the influence of salinity variations on the breeding biology of populations of black clam Villorita cyprinoides (Gray), inhibiting two different cological zones of the Vembanad Lake. Two stations with perennial clam beds, but differing greatly in salinity conditions were selected for the study. Station I, in the northern side of Thanneermukkam barrier, has more influx of sea water and Station II, in the southern side has low saline influx. Monthly collections of black clams and bottom and surface waters were made from May 1989 to June 1990. Major environmental parameters such as salinity, temperature, dissolved oxygen and pH of bottom and surface waters were estimated with a view to understand the circannual variations within and between the stations. Among these, salinity was found to be the most important parameter showing prominent variations. At Station I, the bottom salinity values ranged from 0.0 to 18.12%0 and in Station II from 0.0 to 2.12%0. Histological studies of the clams collected from the two stations revealed that animals inhabiting Station I, a predominantly brackish water zone, have a protracted, almost year round breeding season extending from September to June with peak spawning during March to June and coinciding with the peak salinity levels and temperature. At Station II, a predominantly freshwater zone, the clams have a short duration spawning season extending from March to June with peak spawning during Apirl and May, again coinciding with the peak salinity levels and temperature. It is also observed that there exists a positive correlation between the bottom salinity and gondal maturation and spawning. Size – frequency studies of the calms collected from the two stations revealed that at Station I, the clam fishery was dominated by small sized animals, when compared to Station II. This may be related to the differences observed in the extend of spawning activity between the population of the two stations, resulting in the divergent apportionment of energy resource for somatic growth versus reproduction.
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    ThesisItemOpen Access
    Investigations on head drooping In head-on processed prawns
    (Department of Processing Technology, College of Fisheries, Panangad, 1994) Jose, V T; KAU; Sherief, P M
    Head drooping is the major quality problem associated with processing of headon prawns. The head drooping in head on prawns refers to the condition of oozing out of hepatopancreatic juice resulting from the breakage of the arthrodial membrane, which connects cephalothoraz of prawn to abdomen dorsally. The susceptibility of prawns to head drooping depends on the stability of the arthrodial membrane which in turn is determined by its biochemical composition. In this connection various biochemical constituents of the arthrodial membrane such as protein, phospholipid, moisture, calcium and cholesterol were analysed for two specied of prawn, Penaeus indicus and Penaeus monodon under three size groups (30/40, 50/60, and 70/80 pieces /kg). The activities of various hydrolytic enzymes of the hepatopancreas were also studied. The various biochemical constituets showed significant difference between species. Within the same species a size wise variation in the constituents of the arthrodial membrane and enzyme activity of hepatopancreas was observed. The various unit process such as hauling time, ice storage durations, freezing methods, cold storage durations and thawing methods were studied individually for their influence on head drooping. The study shows that the major determinants of head drooping in prawns are the biochemical composition of the arthrodial membrane and the easiness with which the hydrolytic enzymes of the hepatopancreas are released on postmortem handling and processing.
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    ThesisItemOpen Access
    Role of putative male pheromoneiIn the ovarin maturation of the fresh water prawn Macrobrachium Idella (Hilgendorf)
    (Department of Fishery Biology, College of Fisheries, Panangad, 2001) Patil Chandrakant, Sitaram; KAU; Jose, T M
    Sex pheromones are reported to be present in many crustaceans which mostly have releaser effect on sexual behaviour. The discovery of a male (primer) pheromone with stimulatory effect on ovarian maturation and ovulation has added an important external factor to the basic mechanisms regulating reproduction in fresh water prawns. But studies in these lines are very few in the economically important species of Macrobrachium. Knowledge about this male pheromone will be useful to help or potentiate reproduction and/or extend the breeding period of freshwater prawns, which are of great aquacuItural importance. The present study was carried out in the slender nver prawn, Macrobrachium idella. Seven ovarian maturity stages have been distinguished here. Histological studies of the maturing oocytes helped to understand the changes taking place during oocyte growth and maturation through the progressive maturity stages. Yolk vesicles start appearing in the cytoplasm of oocyte in maturity stage II which is the beginning of vitellogeneis (vitellogenesis I). In stage IV, yolk platelet synthesis starts and 'a peripheral layer of yolk platelets appear in this stage. Later these yolk platelets completely fill the ooplasm through stages V and VI when the ova increase in size enormously. Gonado- somatic index (ovarian index) of different maturity stages was determined and was found useful to differentiate especially the late maturity stages. Ova diameter studies along with the other observations showed a clear picture of protracted multiple spawning in this species with batches of ova undergoing maturation and ovulation in successive maturation cycles. When the females were reared in isolated condition, their ovarian growth was found to be arrested at early stage IV. This restriction of ovarian maturation was found mostly in the second maturation (gonadal) cycle after isolation. But those isolated females which had a common water circulation with males showed normal ovarian maturation and ovulation. Therefore, it can be concluded that a male pheromone exists in this species which is essential for normal ovarian growth and maturation. Another experiment was conducted to find out the tissue source of this putative male pheromone. When these isolated females were exposed to extracts of testis, vas deferens or muscle, both testis and vas deferens extracts were found to stimulate the ovarian maturation and ovulation in isolated females, while the muscle extract (control) was ineffective. This shows that in M idella, the male pheromone is produced by testis and vas deferens or it is produced by testis and transported to vas deferens. Further experiment showed that charcoal extraction destroys the pheromonal activity in testis and vas deferens extract while boiling has no such effect which indicates that the ovary stimulating pehromone in M idella may be a steroidal molecule as reported in some fishes.