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  • Fish  (34)
  • Survey  (23)
  • 2015-2019  (55)
  • 2018  (55)
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  • 1
    Publikationsdatum: 2021-05-19
    Beschreibung: This study was conducted to determine 16 Polyaromatic Hydrocarbons (16PAHs) concentrations in water (during four seasons) and surface sediments (during summer and winter) at eight transects (Astara, Anzali, Sefidroud, Tonekabon, Nowshahr, Babolsar, Amirabad and Turkman) in the southern of Caspian Sea in 20102011. 94 samples of water and 45 samples of surface sediments were collected at 10, 50 and 100 meters depths. In addition, 28 samples of fish (Cyprinus Carpio) were collected during winter and spring. All samples were prepared by Soxhlet and extracting processes and then determined using High Performance Liquid Chromatography (HPLC) instrument. Results of current study showed that mean concentration and standard error (±SE) of 16PAHs water were observed 232 (±77), 1268 (±808), 538 (±190) and 151 (±53) µg/l in spring, summer, fall and winter, respectively. In addition, annual mean contents and standard error (±SE) of 16PAHs water were registered 24.10 (±8.12) µg/l. The Hazard Quotation (HQs) were calculated more than unit and belong to Benzo(a)pyrene and Dibenzo(a,h)anthracene compounds. Mean concentration and standard error (±SE) of 16PAHs sediment were observed 0.77 (±0.23) and 1.21 (±0.64) µg/g.dw in summer and winter, respectively. Also, the annual mean contents and standard error (±SE) of surface sediments were observed 0.93 (±0.33) µg/g.dw. The Hazard Quotation (HQs) were calculated more than unit and belong to Fluoranthene, Benzo(a)anthracene, Chryseneand Benzo(a)pyrene. The annual mean contents and standard error (±SE) of edible tissue of Cyprinus Carpio mussels were observed 2.21 (±0.42) µg/g.dw. Annually, pattern of 16PAH compounds were obtained 10, 70, 12 and 8% for 3,4,5, and 6 rings, respectively. Four ring compounds had high content and percentage and 2 ring was not observed in all samples of water. Also, pattern of 16PAH in surface sediments were obtained 31, 56 and 14% for 3, 4, and 5 rings, respectively. Four ring compounds had high content and percentage and 2 and 6 rings were not observed in all samples of surface sediments during two seasons. Result of Diagnostic Ratios analysis (DRs) of sediments showed that the source of oil compounds were petrogenic and pyrogenic in summer and winter, respectively. Based on DRs in water and sediments were observed oil compounds were either petrogenic or pyrogenic with different percentage in the southern Caspian Sea. In conclusion, the results revealed that in the some transects the 16PAHs concentrations of water were above the threshold levels and more petrogenic (85%) sources which represented polluted condition in this area. 16PAHs concentrations of sediments were below the threshold levels and conditions for this region were showed unpolluted. Also, the Caspian Sea sediments were classified in Class 2 (Fair). According to results of the evaluation’s risks to human health associated with consumption of the mussels containing 16PAHs suggest that there is risk for humans.
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Oil pollutions ; Water ; Sediments ; Fish ; Cyprinus carpio ; Samples ; Polyaromatic ; Hydrocarbons
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 78pp.
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Publikationsdatum: 2021-05-19
    Beschreibung: Persian Gulf waters (areas of Hormuzgan province) in order to determine the best location for installation of Artificial reefs were studied seasonally from December 2006 to March 2007. Distribution of funa and flora and estimation of deposit depth by SCUBA diving method, density and frequency of macrobenthose communities, frequency of ichthyoplankton communities, determination of organic carbon (OC) and Grain size and measurement of water physical factors including salinity, saturation oxygen, dissolved oxygen, temperature, chlorophyll a, in transect and subtransect was studied for recognizing the best placement to installation of artificial reefs. All areas of Shipping, military areas, around of Islands, natural habitats and entrance to jetty were introduced for excluding areas. South of Qeshm Island (transects of Bahman jetty, Bandar Masen and Bandar Salakh) are catching area for small pelagic (sardine and anchovy fishes), therefore in these areas installation of artificial reefs have confined with this restriction. Also entrance to Bahman jetty, sea plant habitats (sea grass and algae) in transects of Bahman jetty and Bandar Masen were considered as restricted areas. In this area, suitable areas for installation of artificial reefs was determined based on distribution of Ichthyoplankton societies for every transect, for macrobenthose enrichment Bahman jetty transect was calculated middle, but transects of Bandar Masen, Hengam island and Bandar Salakh was done good indicator. The deposition depth in transects of Bandar Masen and Hengam island was determined as good factor but this index was known as average factor for transects of Bahman jetty and Bandar Masen. Also, two another indicators, primary production and bottom sturdiness, were calculated as middle factor for Bahman jetty transect, but these indicators were known as good factors for other transects in this area (Bandar Masen, Hengam island and Bandar Salakh). The results of these indicators in transects of Bandar Kong and Bandar Bostaneh in Bandar Lengeh area was indicated that T. O. C and bottom sturdiness indices had no significant difference (p〉0. 05) and the whole of these transects had average priority. Bottom sturdiness, primary productions and macrobenthose communities indices had difference in Bandar Lengeh area (p〈0. 05) and these indices had average priority in Bandar Kong transect and had good priority in transects of Bandar Bostaneh and Bandar Hasineh. Ichthyoplankton community had average priority for Bandar Bostaneh transect, and had good priority for transects of Bandar Kong and Bandar Hasineh. The good priority has obtained for transects of Bandar Charak, Bandar Gorzeh and Bandar Chiroeyah. Also Macrobenthose community, primary production, water physical factors and bottom sturdiness were known as good, good, average and weakness priority respectively for transects of Bandar Charak, Bandar Gorzeh, but primary production, bottom sturdiness, water physical factors and macrobenthose community were resulted as average, good, good and average priority respectively for Bandar Chiroeyah transect . T. O. C index was determined as average priority for transects of Bandar Gorzeh and Bandar Chiroeyah and good priority for Bandar Charak transect. Finally, excluded areas maps, suitability areas maps and feasibility areas maps were drawn by Arc GIS software. In this survey, layers between 10 to 20 meters depth were recognized as the best position for installation of artificial reefs.
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Artificial reef ; Macrobenthose communities ; Ichthyoplankton community ; Organic carbon ; Grain size ; Water physiccal indices ; Dissolved oxygen ; Temperature ; Chlorophyll a ; Algae ; Survey ; Ichthyoplankton
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 123pp.
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Publikationsdatum: 2021-05-19
    Beschreibung: Study of survey health management and diseases in hatcheries and fish farms can help us to knowledge and application control methods such as: prevention, treatment and increase high levels of production in hatchery and farms, finally. This survey carried out from 2005 to 2008 for 4 years in sturgeon hatcheries and farms of Golestan province. Sturgeon fishes include Huso Huso, Ship sturgeon, Acipenser persicus collected and for virology, bacteriology, fungius and hematology examined. Also, physicochemical parameters measured and recorded in different stages of culture. Results of this study showed that all of samples in virology was negative and did not observe any doubetful causes. In bacteriology CFU was variation from 3/9 ×105 to 6/9×10. The most parasites that detected in this survey was Cocolanus espherolanus , Sceria binopsulus semiarmatus and Amphilina fuliacea that separates from Acipenser Percicus, especially. The results about hematology parameters some important hematological indices of ship sturgeon include: The total RBC for female and mail specimens measured as 5.3±1.5 ×105, 4.8±0.5 ×105 per mm 3 respectively. The amount of haematocrit and hemoglobin for female and mail determined: 34.3±2.8, 35±1.4 percent and 10.3±0.9, 8.9±0.8 gr/dl .The MCV: 216.3± 96.2, 736.5± 102.5, MCH: 720.2±309.5, 186±0.7 and MCHC: 30±0.8, 25.5±3.4 percent respectively.The total WBC were (female, male): 21320±1054, 20580±777 per mm 3 and neutrophil: 16.4±2.5, 17±1.4 percent and lymphocyte: 74.4±2.4, 73.5± 0.7 percent and eosinophil: 6±1.4, 6.4±0.5 percent, monocyte: 2.8±0.8, 3.5±0.7 percent. There was not any significant differences (p〉0.05) between mentioned parameters in male and female (students t-test). Also evaluation of hematological parameters in bluga ( Huso huso) include: total RBC were (male , female) 5±0.3 ×105 , 4.9±0.6 ×105 per mm 3 ,respectively and hematocrit: 33.2±6.7 , 35.4±3.4 percent and hemoglobin: 11.2±1.5 , 12.2±1gr/dl and MCV: 669.9±172.2, 723.9±982.4 and MCH: 226.2±42.5, 249.5±35.4 and MCHC: 34.1±2.4, 34.6±3.6 percent respectively. The totals WBC were (male, female): 24800±707.1, 23042±1375.4 per mm 3 and neutrophil: 18.5±0.7, 21.4±1.1 percent and lymphocyte: 73.5±1.4, 68.4±1.1 percent and eosinophil: 5±2.8, 7±1.2 percent and monocyte: 3.5±3.5, 3.2±0.8 percent. According to statistically study the count of lymphocyte had significant difference between male and female fish and this count in male was higher than female. (p≥0.05).
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Physicochemical ; Hematology ; Fish ; Sturgeon ; Huso huso ; Ship ; Acipenser percicus ; Bacteriology ; Parasitology ; Health management ; Diseases ; Survey ; Aquaculture ; Hatcheries ; Samples ; Sceria binopsulus ; Amphilina fuliacea ; Female ; Male
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 395pp.
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  • 4
    Publikationsdatum: 2021-05-19
    Beschreibung: The survey effect of salinity, turbidity and dissolved oxygen performed on Rutilus frisii Kutum juveniles with aim, which was determined about survival rate and histological changes in gill and kidney tissues. Juveniles provided from the Rajai's fish propagation center and then examined in Caspian Sea Ecology Research Center laboratory. The juveniles were investigated on three weight group (200-〈400, 400-〈600, 600-〈1000 mg) and two dissolved oxygen levels (7.6 ± 0.19, 3.8 ± 0.15 mg/L)in fresh water and Caspian sea water(12.5 ppt). Also, six turbidity levels (50 FTU, 430FTU, 2600 FTU, 7800 FTU, 15600 FTU) were probed in freshwater during 168hr. Each treatment has three replications. The factorial test evaluated for survival rate in treatments. The results shown that there was a significant difference among treatments in the different levels of factors, (p〈0.05, Duncan test). The juveniles' survival rate has decreased than control treatment in brackish water and turbidity in freshwater. It was demonstrated that with increasing fish weight, therefore, the survival rate is increased. The lowest survival rates under salinity stress (〉75%) had shown in 400-〈600mg weight group with dissolve oxygen: 3.8±0.15SE mg/l. In addition, the lowest survival rates under turbidity stress (95.83%) had shown that in weight group less than 400 mg with turbidity 15600 FTU. Therefore, survival of juveniles was high. However, gill tissue of juveniles under turbidity and salinity stress became short (necrosis) and thick (edema and hyperplasia) in the end of experiments. The juveniles gill tissues were not changes in the river clear freshwater. Therefore, the factors of gill tissue deformation were salinity and suspended particles in the water. However, the structures of kidney in the different groups of juveniles were similar. Nevertheless, juveniles glomerular diameter increased with increasing weight (p〈0.05, Duncan test). Furthermore, there was a increasing the internal cavity of the proximal and distal tubules and decreasing of glomeruli in diameter in the transfer of juveniles from freshwater to brackish water. Although the survival rate of juveniles is acceptable in this study, but there was abnormal changes in the structure of them gills. It appears that this change will cause a disruption in trend of juvenile's growth.
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Ecology ; Rutilus frisii Kutum ; Juvenile ; Salinity ; Turbidity ; Oxygen ; Survey ; Survival rate ; Gill tissue ; Freshwater ; Brackishwater
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 71pp.
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  • 5
    Publikationsdatum: 2021-05-19
    Beschreibung: The national research plan with title of "Study on health status of Iran Coldwater hatchery and rearing farms" was done in order to identification and tracking of main causative agents of recent mortality in Iran Coldwater hatchery and rearing farms and recognize of infected zones and design of landscape distribution of Epizootic Coldwater fish diseases in the country. This plan was conducted parallel and in same time in some polar provinces of Coldwater fish production such as Mazandaran, Gilan, Ardebil, West Azerbaijan, East Azerbaijan and Kurdistan in three years from 2006-2008. In this regard, about 23,21 and 20 farms in Mazandaran province, 30 farms in West and East Azerbaijan and Kurdistan provinces and 19 farms in Gilan and Ardebil were selected as randomly and tracking were done yearly from 2006-2008. This research was conducted according to regular planning consists of farms visit that was done according to statistical plan and completion of Questionnaires and sampling. The findings in Mazandaran province revealed that fish infections background and infectious diseases were increased in period of 2006-2008. In fact, 56% of all fish farms in 2006, 71% in 2007 and 85% in 2008 were recorded as infected farms. In other side, average weight of fish final products was more 500gr in consume market. So, regarding to long period of fish culture in mentioned fish occurrence of more morbidity could be expected. The streptococcus infections were most important fish bacterial diseases that have more incidence and pathogenicity in collected questionnaires. Also it revealed more occurrences in summer season in above 15oC temperature in affected fish farms. Also, Enteric Redmouth Disease (ERM) and Saprolegniasis were reported as second and third degree in examined farms. Meanwhile, findings of control, prevention and treatment of our survey revealed that using of antibiotics and detergent materials were increased in mentioned province. Indeed, 34.7% of all fish farms in 2006, 71.4% in 2007 and 75% in 2008 have applied treatment operation and using of detergent materials in affected farms. In other side, frequent using of Erythromycin antibiotic was reported several times in 2008 so fish farmer faced to Bacterial resistance and should be using from Florfenicol as alternative antibacterial. Also, in feed sampling from all fish farms about 3 fish farms in 2006 and 5 fish farms in 2008 were faced with food poisoning that originated from high TVN and peroxidase in fish food consumed. These farms revealed mass mortality that stopped after change feeding regime. In conclusion absence of fish health management could be considered as main agent of mentioned mortality in Mazandaran province. The findings of our survey in West and East Azerbaijan and Kurdistan revealed that absence of sufficient experiences in fish farmers and their neglect from water quality concepts, farm cleanness, using of suitable detergent materials for fish ponds and instruments and disability in continuous monitoring of physic-chemical factors of consumed water could be considered as most important problems. So, fish morbidity and mortality, growth decrement and low production rate were expected. Unfortunately, despite the occurrence of infectious and non- infectious diseases in examined fish farms, there were no documents and information about diseases history, clinical signs in dead fish, feeding regime, fish mortality (rate of daily mortality, age and weight of moribund fish), treatment operation, drugs usage, growth rate, physico-chemical factors and fish density. So planning for control and prevention of mentioned diseases were unsuccessful in affected fish farms. Also, occurrence of some epizootic fish viral diseases such as VHS, IPN and IHN were observed frequently with mass mortality about 40100% in some examined fish farms that produced some tragic economic lost in the mentioned provinces. Similarly, some bacterial, fungal and parasitic diseases were observed repeatedly in some inspected farms such as Flavobacterium, streptococcus infections. Also, some unknown causative agents in parasitic diseases were observed several times such as Dactylogyrus, Gyrodactylus, Ichthyophthirius multifiliis, Trichodina, Chilodonella, Diplostomum and fungal diseases such as Saprolegniasis. In conclusion it seems that absence of fish health management, inadequate rate of hygienic technical services, absence of quarantine programs for transfer of new eyed-eggs, juvenile and live broodstocks packages without health certificates from authorized organizations, uncontrolled entry of foreign eyed-eggs (France, Denmark, Australia and Armenia) and neglect in using of suitable detergent materials for fish ponds, instruments, consumed water and infected eggs, not screening of broodstocks in hatcheries could be considered as most important causative agents in occurrence of infectious diseases and main problems in affected farms in mentioned provinces. Similarly, our findings in Gilan and Ardebil provinces revealed that their problems were similar to other provinces. In fact, neglect in establish of necessary Infrastructures in fish farms and dereliction in health management concepts could be considered as main reasons of occurrence of fish infectious and non-infectious diseases in studied fish farms in mentioned provinces. In fact, often fish farms visited hadn't suitable structures without control and prevention approach. There were not observed detergent using, quarantine programs and prevention methods. Entrance of unknown persons, birds and wild animals were ordinary in mentioned farms. Unfortunately level of farmer’s knowledge was low and no training courses and extension programs were planned by authorized organizations. Meanwhile, food storages were unsuitable and food packages were stored in inappropriate situation so poisoning conditions were increased in examined farms. In conclusion it could be finalized that Coldwater fish farms in Gilan and Ardebil provinces situated in insufficient position and correction of current situation are needed urgently. In final elicitation, it would be mentioned that lack of basic infrastructures could be introduced as most important reasonfor spread of diseases, mortality and related economic losses in studied provinces. Therefore, attention to environmental affairs and access to Sustainable Development are recommended. Also consideration of biosecurity regulations and health management concepts would be important requirements for modification and reformation of Coldwater fish farms in examined provinces towards A Better Tomorrow.
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Physico-chemical ; Coldwater ; Fish farm ; Health situation ; Health management ; Diseases ; Survey ; Rearing ; Hatcheries ; Enteric redmouth disease ; Saprolegniasis ; Bacterial ; Florfenicol ; Sampling ; Dactylogyrus ; Gyrodactylus ; Ichthyophthirius multifiliis
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 250pp.
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  • 6
    Publikationsdatum: 2021-05-19
    Beschreibung: This project prepared and implemented during 2013-16 with emphasis on to provide the results of the fish larva projects (identification, abundance and distribution) in the Iranian waters of the Persian Gulf and Gulf of Oman which as well as had already been done by Iranian Fisheries Science Research Institute and affiliated research institutes and centers . Since each marine fish stocks management requires increased knowledge of the life cycle and be complete biological information, obviously implementation and increased field research is essential, on the other hand the results and the availability of data and information to operation and coordination with the scientific community at national and international levels is of particular importance. This is on condition that currently, due to the increasing trend researchers and students Aquatic Sciences and Fisheries, the availability of data resulting from studies and research projects and initiatives will be necessary. The site is currently only in view of identification and distribution of marine fish larva has been prepared in farsi with photo gallery, and english language development and preparation of the site for the international operation there. It is worth mentioning in the same areas and the same site adjacent seas of fish larvae has not been prepared and is not available. So this site can also be considered as reference area. This site is available for researchers, scientist and students as address: http://ifl.ifro.ir/
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Database ; Larvae ; Fish ; Net work
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 38pp.
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  • 7
    Publikationsdatum: 2021-05-19
    Beschreibung: Given the advancement of electronic technologies and the impact of its application on the environment, especially aquatic ecosystems, it is necessary to address its various aspects, to be attended its various aspects, particularly about electromagnetic waves and their effects on fish as the most important aquatic animal with economic aspects. The present study was designed to reduce the dramatic decline in the production of ornamental fish, in particular the koi fish in Zanjan province, and the research application of the provincial fisheries department to investigate the effects of environmental electromagnetic waves as one of the important alternatives to reduce the proliferation of koi fish. In the present study, the effect of mobile electromagnetic waves (900 MHz) on gonadosomatic index (GSI) and Hepatosomatic index (HSI), Luteinizing Hormone (LH), and gonadal tissue structure of male and female fish brooders during 10 days and in 3 experimental groups including: control (without receiving waves), treatment 1 and treatment 2 (each one, 4 times a day and each time for 30 minutes in faced with mobile phones in standby position and calling mode, respectively). Biometry of broodstocks, blood sampling from caudal vein, centrifuge and serum isolation, determination of RBC, WBC, Hb, Hct, MCV, MCH, and LH, dissection, GSI and HIS calculation, Gonadal sampling, and classical histology were done at the end of the experiment. The success of reproductive production in males and females was more than the other two treatments. In both sexes, the HSI index of treatment 2 significantly increased. The lowest mean of RBC, Hb and Hct was in broiler breeders, and the highest levels of WBC and neutrophil and the lowest percent of lymphocyte in male broodstocks belonged to treatment 2. Histological results showed that the number of ovaries in treatment 1 and 2 was significantly higher than control. Atresia and defects in the previtellogenic and vitellogenic oocytes and degeneration in nuclei, cytoplasm, vitelline envelope and membrane folliclar cells were found in the ovarian tissue of the treatment groups 1 and 2. In gonad of male broodstocks, the mean of large and small diameters and the mean of area and perimeter of the testis lobules, and the sperm occuping the lumen of the testis lobules in treatments 1 and 2 were less than control. Epithelial thickness and tissue defect of treatment 1 and 2 were higher in the control group. The histopathological signs observed in the testis tissue of the brooders in treatment 1 were: Degeneration and breakdown in the testis lobul epithelium, abnormal lobular structure, lumens filled with inactive or anomalous spermatogonies and pre-existing of nucleos of sperm cells, testis tissue necrosis, thickness and fibrosis of epithelial wall of lobuls, and cellular degeneration In some of the lobules, and in treatment 2: degeneration and destruction of stroma in some lobules, degradation in a significant part of the testicular tissue, the appearance of alveolus in epithelium cells (destruction of the germ cell nucleus), fibrosis, and filamentation in the epithelium of lobules, thickness and breakdown in the epithelium of the lobules, in some places, and extensive vacuolization in the lumen of the lobules was observed. In general, the results showed that mobile-induced electromagnetic waves (frequency: 900 MHz, wavelength: 1-103 mm) produced numerous negative biological effects on female and male of koi fish, especially male brooders. So, with providing the necessary conditions for reproduction in Koi brooders (including: the temperature of water near 20 ° C, the oxygen level is at least 5 mgL-1, Non-ionized ammonia and nitrite levels of less than 0.05 mgL-1 and pH range near 7), it should be avoid to use of electromagnetic devices, especially mobile phones at the hatcheries and in the adjacent of fish tanks at the reproduction time.
    Beschreibung: Published
    Schlagwort(e): Fish ; Electromagnetic waves ; Gonadal tissue ; Reproduction ; Hematological indices ; Koi fish
    Repository-Name: AquaDocs
    Materialart: Report , Not Known
    Format: 87pp.
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  • 8
    Publikationsdatum: 2021-12-05
    Beschreibung: Regarding the fish farming in cages, taking into account all nutritional requirements appropriate to the needs of aquaculture is essential in order to minimize damage to the environment and achieve maximum growth. Fish nutritionists should be aware about the analysis of ability to digest and absorb nutrients in the diet to prepare and adjust the diet according to the needs of aquaculture. Food must also have appropriate physical properties for food intake with minimal loss of nutrients in the water. Inadequate resources with low quality or energy consumption within food, reduced the growth performance and increased the excretion of nitrogen in the environment. Food must be designed so that the balance of minerals in food will help maintain osmotic pressure within the body of fish in salty water. Food requirements and efficiency of food conversion ratio (FCR) is variable by changing environmental conditions (dissolved oxygen, temperature, water quality, flow rate, light intensity ,day length). The fish of cages are feeding by floating pellets which have the ability to stand in the water column. The floating pellets allows the fish to have sufficient time and opportunity for finding food. But sinking pellets pass rapidly from the cage and are inaccessible to fish. According to the Caspian sea conditions is better the extruded food equipped with Hygenizer to be used that a portion of it remains on the water surface and part of it moves gently down with an immersion mode in the water column (Softly deposited) for fish consumption. The amount, number and time of feeding are important factors to assess the nutritional activities. In general, fish feed from dry food between 2 to 3 percent of their body weight. Food consumption was also varied due to the quality of the food and fish physiological factors such as age, size, stage of life and stress level. Fish food distribution being fed manually or by means of demand, launcher and automatic feeding. The farm managers should pay attention to the things like water flows in the cage, wind, fish appetite, consolidated flows in the cage during food distribution as well as food storage in dry places with proper ventilation system to prevent the growth of fungi and insects activities to prevent loss of food. Also, adding antioxidants to the 100150 ppm when storing dry foods including the important cases particularly in prevention of fish liver lipoidosis disease is considered.
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Cage culture ; Salmon ; Feeding ; Analyze ; Nutrition ; Variety ; Fish ; FCR ; Aquaculture
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 72pp.
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  • 9
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    Unbekannt
    Iranian Fisheries Science Research Institute | Tehran, Iran
    Publikationsdatum: 2021-05-19
    Beschreibung: Epinephelus coioides (family serranidae) is protogynous. This species is one of the most important fishes in food chain of marine proteins of persian Gulf. Therefore knowing about the reproductive biology and physiology of this species is an important role on aquaculture procedures. Monthly samples of Epinephelus coioides were obtained in khozestan Bahrekan province from 2001 to 2002 for annual variation of base line of reproductive hormone. The hormones such as: 17-B estradiol, Testosteron, Progesterone, Gonadotropin I ,II GTHI, II) and cortisol have assayed and also different stages of gonads from the histological point of view were studied by light and electron microscope. Aditional to morphometric and fecundity measurements, the important factors such as : Gonadosomatic index (GSI) Hepatosomotic index (HSI) and Condition factor (KF) were also studied. Environmental factors such as temperature, salinity, photoperiod and pH were analyzed for the determination of effective factors responsible for the changes of reproductive cycles. The flactmation of estroid hormones and gonadotropines show a significant variation in different stages of maturation, e.g 17-B estradiol's concentration in the third stages, GTH II in fourth stages of sexual maturation or final oocyte maturation, plasma Testosteron in post ovulation and Progesterone during maturation indicates the highest levels of above mentioned hormones. The total calcium concentration was high in all year. calcium concentration was correlated with GTH II synthesis and increases with GTH II in June. 17-B estradiol concentration was also correlated with GSI. The high concentration of cortisol throughout the year was an index of stress and development of ovary maturational processes. This species was protogynous synchronous hermaphrodites , and belongs to annual spawning species, being monandric. The sexual transition was found to occure in individuals of 51.2- 105 cm in length. GSI and HSI level confirms the time of spawning period is in April- June. Electrone microscopic studies of gonad tissues showed some changes in mitochondria and endoplasmic reticulum in the post ovulation, maturation and post spawning periods. During the monthly sampling the biochemistry of tissues variations indicated decrease in protein and lipid content, but an increase in water content of spawning fishes which was correlated to the maturation of Epinephelus coioides . sex ratio indicative of higher frequences of females to males during monthly sampling periods. The females were smaller than males in sizes, therefore the females lived in 8-15m depth, but males were living in upper limits of depth. The results indicated that the temperature was the most effective parameter in reproductive cycle of Epinephelus coioides and the mean 24°c was a convenient temperature for spawning. Photoperiod was the second effective. factor on the reproductive cycle for this species. It seemed that the increase in the photoperiod between January to May caused a development of the oocyte. Regarding to the results of this research, it seems that the period of spawning in Epinephelus coioides is in May- June and the aquaculture procedure of Epinephelus coioides could be performed in the above mentioned periods.
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Fish ; Gonadal tissue ; Hormone ; Fisheries biology ; Reproduction
    Repository-Name: AquaDocs
    Materialart: Report , Not Known
    Format: 166pp.
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  • 10
    Publikationsdatum: 2021-05-19
    Beschreibung: Iranian Fisheries Science Research Institute
    Beschreibung: Published
    Schlagwort(e): Hydrology ; Hydrobiology ; Fish
    Repository-Name: AquaDocs
    Materialart: Report , Refereed
    Format: 108pp.
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