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Following-up organic pollutants in the course of producing foods
244-248Views:132We analysed the raw materials in various food products, including additives, carrier solvents and end product for several selected organic pollutants. We analysed these food products for the type of chlorinated hydrocarbon pesticides, polychlorinated biphenyls and other currently used pesticides.
We analysed three product categories: bakery products, canned mushroom and meat products. The analysis of the bakery products and of the canned mushroom did not conclude in positive findings, which means that these products contained the agents given during the production of the product and the environmental pollutants in undetectable low concentration.
However, the results for meat and fish products indicate that polychlorinated compounds are persistent and are of a lipophyl character, as some of these components have been detected in these food products, the concentration of the PCBs were detected in the range of 9.8-24 μg/kg. -
The effects of bioactive feed additives for the production parameters of common carp (Cyprinus carpio) fingerlings in intensive recirculating system
35-41Views:233For the appropriate quantity and quality of fish meat the pond farmers need to use up to date nutrition and feeding technologies. Recently the intensification of the carp production is stepping up with the availability the proper quality of the artificial feeds. The using of different feed additives make a better feed conservation ratio, faster growing rates and more uniform stocks.
In our experiment what is made with common carp (duration of the experiment was 8 weeks long) we compared two different kinds of feed additives in different doses. One of them contains only natural mineral elements and the other additive is a natural origin probiotics. Both additives were used in the quantity of 0.5, 1 and 2% of the total feed. By the result of the 8 weeks experiment it could be said, that the using of the humic acid based mineral elements feed additive. Makes a better FCR comparing with the control stock, but was not as good as the using of the probiotics. At the humic acid treatments the more doses, the better FCR value, but at the probiotics it wasn’t true. The 0.5% probiotic treatment gave the best result. It is concluded that the using of the probiotic feed additives always gave a better performance of the fishes (average weight, biomass, FCR) than the humic acid treatments. The using of the feed additives hasn’t got an influence for the survival rate of the carps.
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Fishes protected of Natura 2000 system in Slovakia
9-12Views:74The timely and effective establishment of Natura 2000 network is one of the greatest environmental challenges for the new Member States of the European Union. Slovak Republic is facing this challenge now. By the June 2005, the Government in our country must prepare a list of sites to be included in the Natura network, according to the criteria set up in the Habitat Directive. Natura 2000 sites, according to the specificEUDirectivesconsistofSpecialAreasofConservation(SACs),andSpecialProtectionAreas(SPAs).TheSPAsandtheSACs, the latter selected as Sites of Community Importance (SCIs), will be incorporated into the Natura 2000 network. The problems of proclaiming the system of protected areas of European importance for the Natura 2000 have been one of the major topics of the ichthyological activities in our country in recent years.
For 3 lampreys and 20 fishspeciestheterritoryofpotentialsiteofcommunityinterest(pSCI)hasbeenlimitedandproposed.Theselection of localities and examinations of population state in individual species of fishespresentedintheAnnex(II.,IVandV.)totheCouncilDirective No. 92/43/EEC were carried out in 2003/2004. In total 179 pSCI localities for fishandlampreysinthealpinebiogeographicregion (83) and in the pannonian biogeographic region (96) pSCI in the Slovak republic were selected and limited. The number of pSCI localities selected for individual species is different regards to their distribution within the river net of Slovakia. For example, for species of general distribution, 30 localities pSCI (Misgurnus fossilis, Rhodeus sericeus, Gobio albipinnatus, Barbus barbus) or 35 localities pSCI (Cobitis elongatoides, Barbus peloponnesius), have been proposed, on the contrary, in several species of exclusive distribution as Lampetra planeri - 8, Gobio uranoscopus - 9 and Zingel zingel -12 localities.
The pSCI territory for individual species of the ichthyofauna presented here represents the firststageintheprocessofcreatingtheprotected territory system of European interest Natura 2000 in the territory of the Slovakia for this group of aquatic vertebrates. The list of proposal sites will have to be submitted to the European Commission by the date of Accession. -
Comparative study of wold and lowland situated small watercourses from fishbiological aspect
54-59Views:66Fishbiological research was held on 10 small watercourses, especially on the streams of woldy region of the southern foot of the Bükk-mountains and on the creeks of the lowland Borsodi-Mezőség in 2004. 7475 specimens of 34 species were caught as the result of our surveys on 28 sampling sites. Significant differences were found between fish stocks living in wold and lowland situated sampling sites.Nevertheless on the border of the hilly and lowland regions continous transition observed in the composition of fishstocks. Using Ind Val 2.0 statistical software indicator species appointed of the stocks of wold situated samling sites in “natural” and in “disturbed” states, and of the lowland situated sampling sites.
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Effect of different n-6/n-3 fatty acid proportion oil sources on reproduction performance and fatty acid profile of milk in modern genotype sows - Pleminary results: Preliminary results
121-128Views:150This study was conducted to investigate the effects of supplemental n-6 and n-3 fatty acids on sow’s milk fatty acid composition during the lactation period and on reproductive efficiency of sows in the subsequent gestation period. Data were collected on a total of 213 DanBred sows (108 control and 105 experimental) representing parity of 2–7, respectively. Control and experimental sows were placed in the same housing conditions during lactation and gestation period. Control group received 6.3 g of sunflower oil (SO) per kg feed as n-6 fatty acid supplementation, whilst experimental animals received the same amount of fish oil (FO) as n-3 fatty acid source. Diets were corn meal-extracted soybean meal based. The experiment was conducted in one replication as being a part of a longer and more comprehensive trial. It was found that the consumed long-chain polyunsaturated fatty acids (LC-PUFAs) appeared in the sow’s milk and changed its fatty acid profile. With this alteration, the n-6/n-3 ratio of experimental (FO) sows’ milk were narrower than in SO group (SO: 13.82 vs. FO: 5.89). The benefits of n-3 fatty acids supplementation were evident for the subsequent reproduction cycle, when experimental sows heated more reliable and earlier than control (weaning to oestrus interval: SO: 5.86 vs. FO: 4.48 days). Only 2.33% of experimental sows (FO) did not heat within 7 days after weaning, but this was 12.36% in the control group (SO). The present study requires further research to evaluate the effect of n-3 fatty acids on maintenance of pregnancy and improved subsequent litter size.
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Preliminary results of intraspecific sterlet hybrid (Siberian sterlet × sterlet) rearing under intensive conditions
17-19Views:129Due to early maturation and a small size, sterlet (Acipenserrut-henus) is a very advantageous fish for intensive sturgeon farming with regard to caviar production. According to our previous observations, the growth potential of Siberian sterlet (A.ruthenusmarsiglii) is higher than that of the European one. In our experiment, sterlet and an intraspecific hybrid (Siberian sterlet × sterlet) were tested under intensive tank conditions. During the 8 weeks of the experiment, survival, growth and size heterogeneity were investigated. According to the results, there were no significant differences in survival and growth but the size heterogeneity was higher in the hybrid. It is supposed that, in our trial, the applied water temperature range (24.0–25.5 °C) was optimal for sterlet, but was probably above the optimal range for the hybrid.