9 research outputs found

    Fluctuation of gonadosomatic index during oocyte development in the narrow-clawed crayfish Astacus leptodactylus (Eschscholtz, 1823) in Aras Dam Lake, Iran

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    This study was carried out with the aim of examining the seasonal reproductive cycle of the female crayfish Astacus leptodactylus from Aras Dam Lake, Western-Azerbaijan, Iran. Gonadosomatic index (GSI), and oocyte size were measured in females sampled seasonally in June, August, November (2011), January (2012). Development of the oocytes was categorized according to the diameter and the presence/absence of yolk granules. The ovary development was accompanied by increasing levels gonadosomatic index and egg diameter. Ovarian development histologicaly related to the seasonal GSI . This index was low in June (0.61±0.05) when oocytes started developing and reached the highest value in November (13.53±0.25), when vitellogenic oocytes were abundant in the mature ovary. Our results highlight the relationship between the ovary development and the GSI and egg diameter in the crayfish A. leptodactylus during the reproductive cycle and held important implications for the management of aquatic species. Thus, investigation of female A. leptodactylus reproduction is highly significant for fisheries managers as well as environmentalists concerned with perpetuating crayfish stocks

    The study of production Artemia enrichment liquid SELCO1 &SUPER2 SELCO with internal capacities

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    Artemia as a live food has multiple applications in aquaculture. Artemia contains few unsaturated 3-omega fatty acids particularly eicozapentanoeic acid (EPA) and has no 6-omega fatty acids particularly decozahexanoeic acid (DHA), so Artemia naplious is enriched to improve its food values. The most famous enrichment emulsion are selco and super-selco made by Euro-American INVE Company. This study was performed to make Artemia enrichment emulsions by internal potentials. At first, the final composition of Artemia enrichment emulsion (selco) was determined in Urmia university chemical analysis laboratory. Then, aquatic fishing resources in south of the country such as eye oil of tuna fish, shark liver, cuttlefish and plant oils of sunflower, olive and beef oil were used. Fatty acids profiles were analyzed by Gas Chromatography (GC). The results showed that cuttlefish may produce 13± 3 % wet weight of fatty acids. We made 3 enrichment oils which contained 60± 10 % of plant and animal oils. These suspensions fatty acids were analyzed and the results were compared with control sample. Field tests were performed on 200000 Artemia urmiana naplious by enriching the Artemia with enrichment emulsions and the products were analyzed by GC. The results indicated that the rate of emulsions absorbance in imported and internal samples were 37.47, 25.30, 18.88, 22.14 and 10.32 respectively. In the next stage, enriched Artemia naplious were fed as live food to 500 trout larvae in Ziveh Aquaculture Company as follows: Treatment 1- Control consisted of new feeding larvae fed by concentrated food Treatment 2- new feeding larvae fed by concentrated food plus un-enriched naplious Treatment 3- new feeding larvae fed by concentrated food plus selco oil enriched naplious Treatment 4- new feeding larvae fed by concentrated food plus emulsion-1 oil enriched naplious Treatment 5- new feeding larvae fed by concentrated food plus emulsion-2 oil enriched naplious Treatment 6- new feeding larvae fed by concentrated food plus emulsion-3 oil enriched naplious The results indicated that treatments 1, 2 had significant difference with treatments 3, 4, 5, 6 from survival rate, growth coefficient, obesity coefficient, total length, food conversion coefficient, final weight and protein percent. Abnormalities rates in treatments 1, 2 had significant difference with treatments 3, 4, 5 , 6 in which enriched emulsions were not used, but these indices had no significant difference with commercial samples which shows internal made emulsions can easily be used. The data were analyzed by one-way analyses variance and Duncan test in SPSS and EXCELL softwares. In conclusion, we can make enrichment selco oils in the country by internal potentials which the foreign samples can be replaced by them

    ORIGINAL ARTICLE The Strategy to Achieve Organizational Vision, Based on Cybernetic Systems, with Emphasis on the Use of Knowledge ManagementA: The Strategy to Achieve Organizational Vision, Based on Cybernetic Systems, with Emphasis on the Use of Knowled

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    ABSTRACT Observation in the government section or governmental agencies have shown that organizations are focusing on specific tasks rather than thinking of the determined goals, and this makes it difficult to measure the effectiveness, unlike the performance measured in terms of the emphasis on budget, and on one hand, we cannot easily set the clear figures indicating the effectiveness of the state apparatus.Inthispaper, wefocus ontheeffectiveness oftheapproachaimed atachieving, that means thearticlestateshowto set the achievement ofthe determined goalsinthe landscape through thecyberneticsystem, and in addition, using advanced technical knowledge began to design the technical complexities and applying the Kaizen strategies and deployment of thecycleof knowledge inorganizations and formation the problem-solvinggroups, has installed the system control operator in the system in order to determine the focus of devices on the effectiveness of each period through this
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