Fangmengenbegrenzungen in der Garnelenfischerei - eine Chance fur weitere Biefangreduzierungen

Aiming for price stabilisation Danish, German and Dutch brown shrimp fisheries agreed on weekly catch limitations for the years 1998 and 1999. This resulted in fishing effort reduction of 18 % of the total number of fishing trips in 1998 and up to 24 % in summer. In that period highest abundance of young plaice occurs in the Wadden Sea which is the fishing area of the brown shrimp fleets of Germany and the Netherlands. Consequently as a side effect a reduction of the total annual by-catch especially of young plaice must have occurred. According to formerly conducted EU-studies and investigations the by-catch reduction due to the agreed catch limitations should have led to survival of millions of young plaice. They give a potential of some extra catch in coming years which is 2,5 % of the total TAC of plaice in the North Sea. Compared to the German TAC in year 2000 the gain equals 44 %. The catch limitations effect on by-catch reduction in 1998 was in the same order of magnitude of the one achievable by technical measures in net selection applied in that fishery and research. A combination of both could substantially reduce traditional by-catch levels in brown shrimp fisheries.Aiming for price stabilisation Danish, German and Dutch brown shrimp fisheries agreed on weekly catch limitations for the years 1998 and 1999. This resulted in fishing effort reduction of 18 % of the total number of fishing trips in 1998 and up to 24 % in summer. In that period highest abundance of young plaice occurs in the Wadden Sea which is the fishing area of the brown shrimp fleets of Germany and the Netherlands. Consequently as a side effect a reduction of the total annual by-catch especially of young plaice must have occurred. According to formerly conducted EU-studies and investigations the by-catch reduction due to the agreed catch limitations should have led to survival of millions of young plaice. They give a potential of some extra catch in coming years which is 2,5 % of the total TAC of plaice in the North Sea. Compared to the German TAC in year 2000 the gain equals 44 %. The catch limitations effect on by-catch reduction in 1998 was in the same order of magnitude of the one achievable by technical measures in net selection applied in that fishery and research. A combination of both could substantially reduce traditional by-catch levels in brown shrimp fisheries.

The effect of the drug colchicine on the early life of fish

The alkaloid drug colchicine is a mitotic inhibitor. The results of this study show that colchicine influence the normal functioning of the mitotic process in Sarotherodon galilaeus, S. melanotheron and the hybrid S. galilaeus, X S. melanotheron leading to the production of unusual chromosomal events such as anaphase bridges, laggards and polyploid cells. These unusual events could have serious genetic implications in the area of variability of the chromosome number. The use of colchicine also produces results with consistent karyotypes and better morphology as well as providing detailed information on the behaviour of the chromosome of the early life of fish. The knowledge of such information will be of great use in cytotaxonomy, fish breeding and in studying the effects of sub-lethal levels of water pollutants on fish

The effect of spirulina (fresh and dry) on some biological factors in Penaeus semisulcatus larvae

Spirulina is a filamentous cyanobacteria with many applications in food and drug industries, as a food in human, aquaculture, vet and poultry industries… . Semi and mass culture of Spirulina carries out in different countries. This study was carried out in five phases in order to produce this microalga in Iran. The first phase, Spirulina pure stock was imported from Indonesia. After identification of species, it was cultured in laboratory until we took 20 liters of biomass. The semi-mass culture was carried out in green house. Cell concentration and size of Spirulina were recorded during culture daily and their growth rates were calculated. After two weeks, when the size of Spirulina was suitable, biomass of Spirulina was harvested then accumulated Spirulina weighted and dried in 24 hours in laboratory. In order to microbiological study, the samples of Spirulina (dry and fresh) were cultured on blood agar medium and coliforms were counted. The chemical composition of produced Spirulina was measured by standard methods. Fatty acid and amino acid profiles were acquired by GC and HPLC instruments, respectively. The amount of chlorophyll in Spirulina was determined by spectroscopy method. Also astaxanthin pigment as an important carotenoid was measured by HPLC in Spirulina and Penaeus semisulcatus larvae fed on Spirulina. At final phase of this project, larva fed on produced Spirulina (biomass and dry powder) was compared to Z plus, microencapsulated Spirulina (M.C.F) and Chaetoceros algae as control. This experiment was carried from zoa to early post larvae stage then survival and growth rate of larvae were recorded. The growth rate of larvae was evaluated with ANOVA test and survival rate of treatments was assessed by Log Rank (Mantel –Cox) test. Also during larvae stage, two parameters of water such as nitrate and nitrite were measured in zoa, mysis and post larvae stages. The results of this study were shown that colifom counts were 1.85×106 and 92.3×105 coliform per ml in fresh and dry spirulina, respectively. Protein percent of dry spirulina was 50.93 % (dry weight) and the amount of astaxanthin in spirulina and larvae fed on spirulina were 0.21 and 0.01 mg/kg, respectively. The most survival rate of larvae were observed in zoa III (88.8%) with Z plus supplement treatment, in mysis III (76.5%) combination of Z plus and dry spirulina in comparative between treatments. Larvae growth (4.5mm) of control in early post larvae was the best.

Survey of veterinery [sic] drug residues, environmental contaminants and mycotoxins of cultured shirmp [sic] in Iran

Economical achievement of optimal growth in developing countries may lead to sustainable poverty reduction. Agricultural activities play an important role in economy and human being welfare, which leads to establishment of food security and quality. Aquaculture products in developing countries share 51.4 percent of total agricultural production.7—percent in developed countries. Therefore undoutedly food production by means of quality and quantity has to be increased .The history of shirmp production goes back to 500 years ago. Today 50 countries of the world produce shirmp .In Islamic Republic of Iran shrimp production started since 1992 in the coastal region of Persian Gulf. The shrimp culture farms canbe classified in to 4 different categories; Extensive, semi-extensive, intensive and super instensive. Global ecological manitenanc is one of the major concerns of authorities Human manipulation of nature is the most destructive activity. Industrial sweage leakage in to the rivers and water sources is a big issue that causes reduction in the aquatic population. Heavy metals have an inhibitory effect in the production and growth of sealife. Human intake of food treated with anti microbial cause's allergy, hypersensitivity and develops microbial resistance. Organochlorine compounds contamination may found in hepato pancreatic tissues of aquatic products, Aresnic may transfer to man via plant & animal product contamination. In 1991 during Persian Gulf Mir 700 oil well set