Acclimatization of juveniles of marine prawn Penaeus monodon to fresh water

Penaeus monodon, hitherto cultured in brackishwater, has been acclimatized to fresh water for culturing in fresh water system. One hundred juveniles of P. monodon measuring in an average 27.7 mm were procured from the coastal lowlying areas near Kakinada in Andhra Pradesh and were used to conduct an experiment on acclimatization. High percentage of survival (96.0%) was observed when the water salinity was lowered gradually at the rate of 10% per day for the first 2 days, 5% per day during the next 2 days and later at the rate of 1% per day.

Studies on certain aspects of eutrophication of fresh water ponds at Barrackpore

In the present study, non-conservative abiotic parameters and biological conditions were utilized to portray the causes, consequences and magnitude of anthropogenic eutrophication in 4 fresh water perennial community ponds at Gangetic West Bengal, India. In order to classify the ponds, a single criterion basis was adopted and more emphasis given to the species of plankton which are biological indicators of eutrophication. Besides this, various abiotic parameters were also studied. On the basis of results obtained, 4 ponds have been classified as "Eutrophic, Tropical Bacillariae".

Studies on packaging of fresh fish

Studies conducted in the laboratory and field have shown that iced fish can be preserved for longer periods in fresh and edible condition in conventional bamboo baskets by providing additional insulated linings of double layer of gunny and polythene or bitumen coated kraft paper. The quality of fish is adjudged by chemical and organoleptic evaluations.

Determination of ubiquinone and tocopherol in heart, liver and muscle tissues of fresh water fish, Rohu (Labeo rohita, Hamilton)

The liver, heart and muscle tissues of Rohu, (Labeo rohita, Hamilton) were examined for their ubiquinone (UQ) and tocopherol contents. These three tissues contained respectively 11.60, 3.94 and 0.19 mg of ubiquinone and 10.16, 5.32 and 3.58 mg of tocopherol per 100 g. The 4% (V/V) of diethyl ether (EE) in light petroleum ether (PE) fractions of all three tissues on paper chromatographic separation gave spots having the same Rf value as standard ubiquinone-50 (UQ 10). Both the 4% and 6% (V/V) diethyl ether in light petroleum ether fraction of liver, heart and muscle tissues gave a single spot with the same Rf value as α – tocopherol.

The bacterial flora and their possible association with spoilage in a variety of fresh-water fish: Cyprinus carpio. var. communis

The bacteria from a variety of fresh-water fish, Cyprinus carpio. var. communis, showed the presence of micrococci, Gram positive and Gram negative rods. These have been characterized as far as was possible. Of thirty-eight strains of bacteria used, only six strains were considered as causing spoilage of fish flesh in experiments where flesh was incubated with individual cultures of the bacteria. These six strains had been found on the surface and/or intestine of the fish and support the suggestions that, after death, invasion of flesh by bacteria from the surface and intestine could be the cause of bacterial spoilage of fish.

Preliminary experiments on electrical fishing in fresh watter [i.e. water]

Fishing using electricity is a new technique and is still in the experimental stages in many of the advanced countries. While no published records are available in India, considerable work has been done in Germany, United States, Canada, and United Kingdom. These papers mainly deal with the behavior of the fish in the electrical field, the physiological effects of electrical current on fishes, methods of electrofishing, electric fencing etc. The following experiments on electrical fishing were conducted with a view to studying the distribution of electrical field when an alternating current is passed through two fixed electrodes in fresh water and to study the reaction of different fresh water fishes to the field.

Quantitative and qualitative studies on the bacterial flora of fresh sardines

Plate counts at R T and 8 C on the skin with muscle and the gut contents of absolutely fresh sardines (Sardinella longiceps) caught off Cochin showed a seasonal variation when sampling was done over a period of 12 months. The counts of the gut contents ran parallel with those of the skin with muscle, but at a higher level of magnitude. Qualitatively, the analysis of 360 strains of bacteria isolated from the skin with muscle and 100 strains from the guts during a year's study revealed a very high preponderance of Gram negative rods, mainly of Achromobacter, Vibrio, and Pseudomonas groups. The percentage of Gram positive organism was very low or nil at times in the ocean fresh sardines.

The narcotising impulse threshold values of certain fresh water fishes

The effect of impulse current on the fish at a particular impulse rate and voltage depends on the size and kind of the fish. It is directly proportional to the temperature and inversely proportional to the conductivity of the medium.

Preservation of fish by freezing and glazing. Pt. 1. Bacteriology of fresh, frozen and glazed fish

Microbiological investigation of fresh and frozen fishes such as pomfret, surmai and mackerel was carried out under various conditions of preservation. Glazing, block-freezing and preservation in gunny bag were affected. Determination of bacterial load and isolation, identification and classification of the resistant bacteria were made. Spore-formers of Subtilis mesentericus group were found to be resistant to freezing as well as glazing by ascorbic acid, citric acid and sodium nitrite except a mixture of sodium chloride and glucose. Bacterial load was reduced to a good extent and maintained low till the end of frozen storage period.

Fresh water fishery resources

The inland fresh waters of the island can be roughly divided into the following as far as fish production is concerned: (a) Perennial shallow irrigation reservoirs of the low-country, comprising about 120,000 acres. (b) " Villus" or flood lakes of the low country many of which are perennial, comprising about 30,000 acres. (c) Seasonal village tanks, mainly in the low-country, comprising about 30,000 acres. (d) Deep reservoirs (irrigation as well as hydro-electric) occurring in up-country and low-country comprising about 50,000 acres. (e) Rivers and streams comprising about 20,000 acres. The total area of all these waters is about 250,000 acres.

Enhancing capacities of fishing communities: ICSF-BOBLME sub-regional dialogue on labour, migration and fisheries management. Report of the proceedings, 11 to 13 December 2013, Chulalongkorn University,Thailand

This report on the “Sub-regional Dialogue on Labour, Migration and Fisheries Management”, held at Chulalongkorn University, Bangkok, Thailand, from 11 to 13 December 2013, highlights the issue of migrant labour on board fishing vessels and the problems migrant workers face in their workaday lives. This report will be useful for students, researchers, activists and anyone else interested in matters related to fisheries and small-scale fishing communities.

Survey of the regional fish trade

Fish export trade,both regional and international, has significantly contributed to uganda's economic growth and to the livehoods of many Ugandans in terms of revenue and employment. while there is substantive information on local and international fish trade on which decsions could be based to appropriately develop the trade,informatrion on regional fish export trade is lacking and where avaliable,it has not been adequately documented. This report contains the findings of the survey on regional fish trade at the border district of West Nile,South/Western and Eastern regions key markets and selected fish supply beaches on Lake Victoria.

The storage of red snapper (Lutjanus spp.) in ice, chilled sea water and chilled fresh water

The results are given of trials conducted to determine the effect on quality of holding fish (Lutjanus species) in chilled freshwater and also to compare the quality loss of fish stored in chilled seawater and chilled freshwater and in ice. No adverse effects were observed when storing in chilled freshwater apart from loss of external appearance after 6 days storage; taste panel tests showed acceptable conditions up to 15 days. Chilled seawater is unsuitable for storage as it spoils the intake of salt from the medium, making the flesh unpalatable.

The morphometrics and the proximate composition of the edible fresh water mussel Lamellidens lamellatus (Lea) from Bathalagoda tank, a man made reservoir in Sri Lanka

Morphometric characteristics of Lamellidens lamellatus were studied using a random sample of 138 individuals collected from Bathalagoda reservoir in Kurunegala district. The largest number of individuals in the collection was between 40-50 mm in length. They had a body weight between 60-80 gm. The most abundant bio-chemical component in the adductor and in the foot was protein. Carbohydrate and lipid quantities were almost equal while ash showed the least value. The total protein content ranged from 48.8% to 73.4%; the carbohydrate content from 12.64% to 23.8%; and lipid content from 12.0% to 28.1% of their dry weight. It was found that there were significant relationships between the length and the body weight; and between length and volume.