Artificial spawning by stripping in Dussumieria acuta, a marine pelagic fish and studies on its early development

Artificial spawning was successfully conducted in Dussumieria acuta Valenciennes (Family: Dussumieriidae), a marine pelagic fish, by stripping the fully ripe female and male. The experiment was conducted on board a privately owned shrimp trawler operated in the Palk Bay, by participating in one of its night fishing trips, on 2nd March, 1973. The stripped eggs and milt were mixed in filtered sea water. Majority of the eggs were fertilized. Detailed microscopic studies were conducted the next day in the laboratory. The first larva hatched out 24 hours after fertilization. The larvae could be reared only upto 48 hours after hatching. The developmental stages of the embryo and the larva are described and discussed. It is suggested that the technique of artificial spawning by stripping and early ranching of the embryos into the sea, if arried out by the fishermen in a variety of commercially important species which it is possible on board the fishing vessels on a large scale, can increse the natural production

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Problems in Strong Uniform Distribution

Abstract In 1923 A. Khinchin asked if given any B ⊆ [0, 1) of positive Lebesgue measure, we have #{n : 1 ≤ n ≤ N : {nx} ∈ B} → |B| for almost all x with respect to Lebesgue measure. Here {y} denotes the fractional part of the real number y and |A| denotes the Lebesgue measure of the set A in [0, 1). In 1970 J. Marstrand showed the answer is no. In this paper the authors survey contributions to this subject since then. </jats:p

Carangid resources of India

A review of the research work carried out so far on various aspects of the carangid resources has been made in this paper based mainly on the published contributions of Central Marine Fisheries research Institute. The fluctuations in the fishery since 1950 and its present status, in the light of the improved tackling devices and changed fishing patterns, have been analysed. A drastic increase in the landings was noticed since 1985 which was mainly due to the mechanization of the country crafts, the use of purse seine and ringseine, intensification of trawling and the introduction of multiday fishing. The studies on the food and feeding habits have revealed that almost all species of carangids are pelagic carnivores, feeding mainly on a variety of smaller crustaceans and fishes. The stock assessment studies conducted on certain commercially important species have shown that most of them are either optimally or under-exploited and hence there is scope for increasing the production without adverse effect on the sustainability of the stocks

Exploitation of the brown mussel Perna indica (Kuriakose and Nair) from selected centres along The west coast of Tamil Nadu

The brown mussel, Pema vndica. Is found abundantly on intertldal and subtidal rocks along This study was undertaken to determine the current level of exploitation from selected centres along the west coast of Tamil Nadu, since estimates of catch and effort form part of the basic information required for fishery management

On the occurrence of the soft-shelled turtle, Pelochelys bibroni (Owen) in marine environment

A soft-shelled turtle, Pelochelys bibroni (Owen), caught alive from Palk Bay — a new record from the sourther part of lndian peninsula — proves beyond doubt that the species can tolerate the marine environment, as against the belief that it is purely a freshwater form. The behaviour of the animal was studied keeping it under captivity for 14 days

On the Lebesgue measure of the expressible set of certain sequences

AbstractThe paper gives a condition for the expressible set of a sequence to have Lebesgue measure zero