981 resultados para Drinking age
Resumo:
A compilation of all the available information on the main small pelagic fish resources of Mozambican waters is presented. Resource data on distribution areas, reproduction, age, growth and stock size are described. Actual catch and catch per unit of effort of the commercially exploited stocks are also given. Results of the preliminary assessment of the stocks of scad and mackerel and the problems involving the assessment of Kelee shad stock at Maputo Bay are discussed.
Resumo:
Reproduction, age and growth of Decapterus macrosoma Blecker, 1851 were studied. The data were collected in Sofala Bank from commercial bottom trawlers and surveys. A total of 5,500 individuals were examined during the period 1979-1982. The species is caught in the same areas as D. russellii, but appears in lower quantities. Two main spawning periods a year, one in December-February and another one in June-September were found. Ageing was determined by counting daily growth rings in the otoliths. The parameters of von Bertalanffy's growth equation were L infinity=26 cm and K=0,6/year. Males and females seem to grow at the same rate.
Resumo:
Age, growth and reproduction of H. kelee were studied, and a brief description of its fishery in Maputo Bay (Mozambique) is given. Most material was collected from gill net fisheries during 1977-1980, but some was taken from shrimp trawlers operating in the same area during 1980-1981. Main spawning takes place during October-January with a peak in December. There is also some evidence that spawning takes place during June-July. The size at first maturity was approximately equals 14-15 cm. Ageing was carried out using primary growth rings in the otoliths and length-frequency analysis of fish caught by shrimp trawlers. Von Bertalanffy's growth equation parameters were determined. Males and females grew in similar fashion. There are seasonal trends in the catch composition of the gill net fishery, showing high values during April to September and low during October to December.
Resumo:
Age, growth and reproduction of D. russellii were studied. Most of the material used was caught by the commercial fishing fleet, operating in the Sofala Bank (Mozambique) area. A total of 68,000 fish were examined during the period 1979-1981. There were 2 main spawning periods each year, one in February-March and another in August-September. The sex ratio was about 1:1. Ageing was carried out using primary growth rings in the otoliths and analysis of size-frequency distributions. The parameters of the von Bertalanffy's growth equation were determined. Males and females grew at the same rate.
Resumo:
Age structure and growth profile based on the scale studies of 468 specimens ranging from 17-62 cm total length of Labeo calbasu (Hamilton) from Harike wetland (30°13'N, 75°12'E), Punjab, India have been described, the present study showed better growth in terms of two important growth parameters namely index of species average size and population weight-growth intensity. Two distinct phases in its life history have been described that indicates the optimum exploitation of this species from this water body. Harvestable size is found to be fish of 34 cm total length. The detailed structural elaboration of scale (normal, regenerated, lateral line) has also been done using scanning electron microscopy (SEM).
Resumo:
Effects of age and season on the developmental capacity of oocytes from unstimulated and FSH-stimulated rhesus monkeys were examined, Immature cumulus-oocyte complexes were matured in vitro in modified CMRL-1066 medium containing 20% bovine calf serum and
Resumo:
Samples were collected to study the age and growth of Labeo calbasu (Hamilton) from the river Ghaghra (Guptarghat centre, Faizabad). The scales of L. calbasu have been used for age and growth studies in present paper. Study of the marginal rings on the scales of L. calbasu indicates their annual nature. The fish attained growth in 1st 18.7 cm, 2nd 27.8 cm, 3rd 35.7 cm, 4th 41.8 cm, 5th 46.9 cm, 6th 54.9 cm and 7th 57.4 cm years of the life. The growth rate was observed 18.7, 9.1, 7.9, 6.7, 5.1, 8.0 and 2.5 cm for 1st to 7th age classes respectively. The age groups 1+ to 4+ constituted 91.17% of the total exploited population and 8.83% of remaining age groups (5+ to 7+). The maximum exploited population was observed in 2+ age group with 33.68%. Overall exploitation pattern was systematic and a good indicator for heavy recruitment.
Resumo:
A study was conducted in the Cochin area of India to determine the effect of drinking water on Vibrio parahaemolyticus, a bacterium that contaminates fish harvested from marine and estuarine environments. Times of fresh-water exposure required to inactivate these bacteria are given. Findings indicate that the washing of fish and equipment used to handle the fish in drinking water may decrease in the number of viable Vibrio cells and thus aid in prevention of food poisoning.