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Not AvailableThe annual average threadfin bream landings from 50 252 trawl units was 1 928.5 tonnes in Veraval during April 1S87 — March 1990. The catch per unit effort was high during December - March. Nemipterus japonicus, whi:h formed 82.6% of the threadfin bream landings, matured at 180 mm total length. The von Bertalanffy growth parameters were K = 0.733, t„ = - 0.1167 and L_ = 337 mm. N. japonicus preferred to feed on crustaceans especially Aceles spp.Not Availabl

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Not AvailableDuring October 1987 to March 1988 the total estimated oil sardine, Sardinella longiceps, landed by cast net at Poibander was about 1 300 tonnes with an average monthly landings of about 21S.9 tonnes. The length (L)-weight (W) relationships of male and female were W = 1.514 + 2,744 L and 4!237 + 2.617 L, respectively. The mean modal length increased from 75 mm in October - November to 155 mm in Febmary - March. The stage of maturity progressed from immature in October to maturing (stage IV) in March.Not Availabl

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Not AvailableCasein-gelatin based iso-nitrogenous purified diets with graded levels of lipid (0,5,10,15, and 20 %) were fed to the fingerlings of Liza macrolepis for 60 days to evaluate the changes in growth, feed conversion and carcass composition. Absolute, relative and specific growth rates were found to be higher and FCR better in fishes receiving 5 % dietary lipid level. Carcass composition indicated that lipid, carbohydrate and ash were significantly different, while protein deposition was found to be not significantly varied from the initial values. The studies showed that a dietary lipid level of 5 % was optimal for the species for proper growth and feed conversion.Not Availabl

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Not AvailableAcid and alkaline phosphatase from different organs such as muscle, gonad and hepatopancreas of FindiCuS at different stages of maturation were investigated. Eyestalk ablated shrimps were placed in different salinity (20, 25 and 30 ppt) and alowed to develop gonads. Similarly shrimp from the wild were collected and segregated according to their stages. The sample from different salinity alkaline phosphatase. In all treatment and wild were analyzed for acid and However, the samples analyzed, acid phosphatase activity was higher than alkaline phosphatase the highest activity for both the enzymes were observed in gonads hepatopancreas followed by muscle and gonads whereas in the descending in muscle and order. During gonadal maturation, there was a rapid increase of both the enzymes in hepatopancreas enzymes were the enzyme activity decreased in all the salinity tested. Both the sensitive to changes with the decrease in both the activities of environmental salinity. At lower salinity (20 ppt) there was a both the enzymesNot Availabl

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Not AvailableVariations in the biochemical composition of muscle, gonads (anterior, middle and posterior) and hepatopancreas were studied during ovarian maturation in the Indian white shrimp, Fenneropenaeus indicus. Among the biochemical composition, protein was found to be dominated followed by carbohydrate and lipid. During ovarian maturation, protein content was decreased in muscle and gonad whereas in hepatopancreas protein increases. Carbohydrate content in muscle decreases whereas its level increases in all other organs investigated. Lipid content increased in ovary during maturation whereas in muscle and hepatopancreas decline of energy reserves which indicate that hepatopancreas is the main source of glycolipoproteins contributing to the vitellogenic process. There was a significant difference between the stages are observed.Not Availabl

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Not AvailableThe banana shrimp Fenneropenaeus merguiensis is an important alternative commercial cultured species. Presently, the industry is on a look out for an alternative species for shrimp culture. An experiment was conducted to determine the growth and survival of juveniles F. merguiensis using live feed (clam meat, and polychaete worms) and a commercial pellet feed. In 45 days of feeding, the weight gain, per day growth, specic growth rate and survival registered by the shrimp were analyzed and compared. Among the feeds given, clam meat showed highest percentage gain in weight (369.8 %) followed by polychaete (240.4 %) and commercial pellet feed (173.9 %). The survival rate amongst the three treatments did not show any signicant variation; however the highest rate was recorded in shrimps fed with polychaetes, clam meat and pellet feed. The ammonia and nitrite concentration in water showed distinct uctuations in the treatments especially shrimps fed with polychaete worms. Live feeds have imparted faster growth and survival in the present study indicating that early stages of banana shrimp have preference over pellet feed and strategies can be developed to have feeding regimes having a combination of live and pellet feeds.Not Availabl

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Not AvailableA shrimp feed formulation, consisting of fishmeal, squid meal, prawn head meal, soybean meal, cereal flour (different sources), fish oil, lecithin and other feed additives was selected for evaluating aquastability of different sources of starch namely, corn flour, maida flour, rice flour, tapioca flour and wheat flour as binders at 15.3% each in combination with guar gum at three levels of 1, 2 and 3%. The feed pellets were prepared (3-5 mm length, 3mm diameter) by adding 40 ml water for 100g dry powdered feed mix followed by steaming, pelleting in hand pelletizer and drying at 70o C. The aqua-stability of feed pellets was determined by measuring the loss in weight of pellets soaked in water and the turbidity of water as Nephlometer reading (NMR). Among the starch sources tested, maida flour in combination with 2% guar gum in the feed imparted better aqua-stability to pellets followed by tapioca flour, rice flour, wheat flour and corn flour. Further increase in the level of guar gum in feed had no beneficial effect. It was observed that pellets containing guar gum rapidly swelled and developed cracks and these effects were higher with increase in guar gum level. Feed pellets containing wheat flour and tapioca flour showed highest Nephlometer reading (water turbidity), while pellets with maida flour showed the least NMR followed by corn flour and rice flour. While addition of 1% guar gum considerably reduced the NMR of tapioca flour and wheat flour, incorporation of 2% guar gum resulted in the least NMR reading of pellets with wheat flour and maida flour. However, further increase in guar gum (3%) has no beneficial effect. But raising guar gum level to 3% decreased the NMR reading in the case of tapioca flour and increased the NMR of rice flour and corn flour. Feed pellets of the same shrimp feed formulation containing wheat flour along with 2% guar gum and processed in a commercial scale ring-die pellet mill having three stage conditioners and steam injection facility, showed good water stability up to 4 hours (79.5 % stability).Not Availabl

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Not AvailableThe State of Gujarat has a coastline of 1600 km. The lowlying and certain other areas adjacent to the coastline offer immense potential for the development of brackishwater aquaculture. The Government of Gujarat has been mounting lot of efforts to harness the full potential for the development of brackishwater aquaculture in the coastal zone of the State. These efforts have been yeilding positive signs of improvement in the level of aqua production and in the export price of shrimps, thereby reflecting an increasing trend in the earnings of the aquafarmers. These developments are indicative of an optimistic scenario for the further expansion of shrimp farming in the State. In this background, the available resources, infrastructure, current farming practices, production and marketing constraints and initiatives of Central Institute of Brackishwater Aquaculture, Chennai in tackling certain research issues of concern related to the activity are described in this contribution. Brackishwater Potential in the Coastal Districts of Gujarat . There are 12 coastal districts in Gujarat, viz., Valsad, Navsari, Surat, Bharuch, Anand, Amreli, Junagadh, Bhavnagar, Jamnagar, Porbandar, Kachchh, and Rajkot. Among these, Kutch district has the maximum coastal length of 406 km. In regard to the extent of adjoining land along the coastline is concerned, it is assessed that Bharuch district possesses the maximum adjacent of coastal land (33,208 ha) suitable for development of coastal aquaculture. The total land allotted so far to farmers along Gujarat coast for shrimp farming is 4,287.95 ha. As at present, maximum extent of coastal land was allotted to farmers in Navsari district (1,467 ha) for the development of shrimp aquaculture. Tidal amplitude of Gujarat coast is higher than in the other parts of West coast. Although 3.76 lakhs ha of brackishwater area is available in the State, the Department of Fisheries, Govt. of Gujarat has estimated that about 89,341 ha are suitable for the development of brackishwater aquaculture.Not Availabl

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Not AvailableIn Saurashtra waters, where fishery resource is currently being well exploited by private sector, explora tory survey programmes are being conducted by Govern ment of India. The log records of these exploratory surveys have been provided to Veraval Research Centre of CMFRI for analysis and interpretation. The results of analysis of the data based on trawling survey con ducted by M.V. Meena Prapi (overall length: 17.5 m) belonging to Fishery Survey of India (Base: Porbandar), Government of India are reported here. The analysis, based on 4 year survey (1985-'88), is presented here with a view to provide information and to extend our knowledge about the spatial and seasonal distributionNot Availabl

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Not AvailablePresent study reveals the variation in wet weight at harvest (4 months in pond) and resistance to white spot syndrome virus (WSSV) in the kuruma shrimp Marsupeanaeus japonicus. Eight families obtained from gravid female shrimp from wild and two inbred families were used. Representatives from each family were challenged with white spot syndrome virus. Survival curves in a challenge experiment revealed no difference between wild and inbred families. However, one family each from wild and inbred had higher median survival compared to the rest. Analysis of the wet weight at harvest revealed sexual dimorphism for growth with female weighing heavier than their male counterparts. Heratibility was revealed sex wise for harvest weight using a full-sib correlation method. The estimates indicate that harvest weight would respond readily to selection.Not Availabl