145 resultados para Islamic civilization


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Sea cucumbers belong to phylum Echinodermata, order Holothuroidea are an abundant and diverse group of Invertebrates, with over 1400 species occuring from the intertidal to the deepest oceanic trenches. Sea cucumbers are important components of the food chain in temperate and coral reef ecosystems and they play an important role as deposite feeders and suspension feeders. Rapid decline in populations may have serious consequences for the survival of other species that are part of the same complex food web,as the eggs, larve and juveniles constitute an important food source for the other marine species including crustaceans, fish and mollusks. In addition sea cucumbers are often called the earthworms of the sea, because they are responsible for the extensive shifting and mixing of the substrate, and recycling of detrital matter. Sea cucumbers consume and grind sediment and organic material into finer particles , turning over the top layers of sediment in lagoons , reefs and other habitats and allowing the penetration of oxygen. While the taxonomy of the holothurian families is generally well known , the distinction of similar species is difficult. There are relatively few holothurian taxonomist.Most sea cucumber species can be identified by Holothurin taxonomists by using the calcareous skeletal ossicles found in the body wall. In this study , at first a sea cucumber from Kish island in Persian gulf has recognized. Individuals collected from west and east extend far away into north and south of coral reefs by diving. I have checked them morphologically and anatomically.Then with key to the orders of the Holothuroidea, They belong to the Aspidochirotida with key to the families of Aspidochirotida, they were in Stichopodidae families and with key to the genus of Stchopodidae, they were Stichopus. Then ossicles were extracted at National Museum of Natural History, by Dr David Pawson. The ossicles were measured on a transect across a slide prepared from the mid-dorsal region of each specimen.The one we have in the shallow waters of Kish island, is Stichopus hermanni, a massive holothurian, body broad, considerably flattened ventraly ,the dorsal side slightly arched and the lateral sides almost vertical; body wall fairy thick and soft ; mouth subterminal; anus central; tentacles usually 20 in number of length and leaf shaped. Numerous ossicles consisting of table with large discs having usually 7 to 15 peripheral holes, but often irregular or incomplete and spire of moderate height ending in a group of spinelets, rosettes of variable development, and c-shaped rods. Color (exept papillae)partly remained after preservation in alcohol which is found at the depth of 4 to 8 meters, on coral reef. Furthermore, the sexual reproductive cycle was described using standard methods. Gonads were removed and transferred to Bouin's fixative for four weeks and then processed according to standard embedding technique. To prevent the loss of tubule contents during embedding, the tubule sections, were cut well beyond the segment selected for sectioning. For each individual, six sections, each section with 5µm diameter by microtome were cut from tubules. These sections were first placed on gelatin coated slides (the gelatin was heated to 42°c) and then transferred to the oven at 37°c for one hour. This technique usually prevents the fragil tubules from breaking and the loss of gametes. The slides were stained with Eosin and Hematoxylin, and good resolution of the various cell types achieved.A second series of slides was stained with the Periodic Acid Schiff(PAS) to identify polysaccharides(glycogen). Monthly sampling was occurred.The sexual reproductive cycle was defined through the combined use of these criteria: Monthly percentages of the gonad stages for each sex, the monthly gonad index (GI) , given as the ratio of the wet gonad weight (G) to the dray weight (DW)and the monthly percentage of individuals that undetermined sex. The gonad consists of two tufts of tubules on which saccules develop. Gonadal development was classified into five stages: post spawning, recovery, growth, advanced growth, and mature stage that were adapted from the earlier studies of holothurians. Histological preparations showed that the sex of larger individuals could be identified by the presence of oogonia and young oocytes in females, and spermatogonic stages in males.The mean diameter of the tubules and gonadal mass follow annual cycles, increasing from late winter through spring, and dropping abruptly after spawning in the summer. Gametogenesis is generally a prolongate process and begins in March. By summer the ovarian tubules contain oocytes with diameter of 120-240 pm and the testicular tubules contain an abundance of spermatozoa (diameter 5-6 gm ).Following spawning the predominant activity within the spent tubules is phagocytosis of the residual gamets.The active phase of gametogenesis (March to July), coincides with an increasing photoperiod regim, and an accelerated gametogenesis occurs in July when temperature is high. Throughout the year, the gonad of Stichopus hermanni is larger in males than in females, and this is due to the number of tubules in the testis rather than to tubules length or diameter.

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Moon oxygenases related to cytochrome P450s are the molecular Biomarkers which have important role in Biotransformation of endogenous and exogenous compounds and catalazyin of many biological reactions. One of the important isoenzyme is cytochrome P4501A. This isoenzyme involved in metabolism of environment pollutnts such as PAHs. Because of its inducibility, it has a key tool for impact assesment of contaminants in aquatic environment. In this study, at first, that fractions containing Acipenser persicus and Huso huso isoenzyme were purified, and after that Antibodies against them were prepared. For isolation of isoenzyme fraction, Microsomes were prepared from fish liver using differential centrifugation at high speeds. microsomes were solubiized by cholat sodium and Emulgen. Extraction of this isoenzyme was done with the combinatuion of ionexchange chromatography and gelfiltration or chromatofocusing chromatography. Ion exchange chromatography and gel filtration were applied in DEAE sepharose fast flow and sephacryl S200 respectively and chromatofocusing was done at poly buffer 74 and 94 exchanger. The results of SDS-PAGE Showed that the molecular weight of isoenzyme was about 58±1 KDa. Furthermore the inmunoblotting results confirmed this subject. Isoenzyme activigy based on EROD (Ethoxyresorofin o-deethylase) reaction showed about 20-26 fold increase in enzyme activity of treated fish than control fish. The results of Elisa, Using monoclonal anti cod P4501A demonstrated the inducibility and highly elevated of its activity in treated sample more than the control fish. Mean while, the fish sample were showed the strong reaction to polyclonal antibody against beluga P4501A1 prepared in our Lab compared to monoclonal anti body.

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One of the most important marine ecologic phenomenon , is the study of animal community among the bed or benthic fauna. Macrobenthoses are the graet part of the benthic faune , that are more biomasses than meiofauna and microfauna. To study polychaetes diversity of Mangroves, located in Khoore-Khooran , sampling was conducted on a bimonthly and carried out from December 2001 to October 2002. Bottom samples were collected by Van Veen grab (0.025 m2)at 6 station from 2 transect Insitu measurement of temperature , pH , Do and salinity were done . Atotal of polychaetes werw identified within study 32 Family and 43 Genus . Cirriphormia and Nephtys were the most dominant genus in the studies . The range fomumerical abundance of polychaets was between 3006 per m2 in the station A3 to 559individual per mein the station A1 and the variation was done to different bottom , texture the variable environment conditions govrtneng the different parts of each creeks as well as within creeks . Application of diversity indices (Shannon H') on the dominant polychates assambladges has higher H' in the Azar and lower 1-1/ in the Mehr . and the stations B3 has the highest H' and the station A2 has the lowest H' Application of diversity and Richness, Evennes were studied and showed that the station A3 has the lowest evenness and the most individual , and station A1 has the middle pollution.

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Amoungst the three spiny lobster species in southern Iranian waters, Panulirus homarus is the only commercial species with a total landings of 20-45 tons per year indicating a decrease in both landings and CPIJE in recent years. Fishing has been regulated according to the no. of fisherman and effort, and trap ha's replaced the gillnef since 1994. Fishing is carried out along the rocky shores of Chah-Bahar region through different landing places by local fisherman for a period of about two months. Most of catch is exported mainly frozen. This research was sposored by the Fisheries Research Dept. and aimed to work on the population dynamics and stock assessment in order to stablish a better understandings of the stock and hence a proper management in this region. Sampling was done for. 10 successive months in _5 major landing places from 1994 to 1995 with no sampling during the monsoon period through June to July. Althogethere, 8500 specimen were collected and the biometry was done accordings to the sex, region and month. Average total length, total weight and carapace length was obtained 216mm., 452 gr. and 75mm. respectively. Total length-weight relationship of both sexes was calculated and follows the cubic law. Regression coefficients for both sexes was 2.8231, males 2.9616, total females 2.7490, berried females 2.6611- and non-berried females

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Class Condrichthyes consist of two sub-classes: Holocehali and. Elasmobranchii, the second one are more divers and has more importance. Selachimorpha (sharkes) and Batidoidimorpha (rays and skates) are two super-order of Elasmobranchii, which they have crucial role in ecological balance in marine ecosystmes. Except few cases, most of sharks and rays (rays and skates) are not well identified, so a lot of works need to be done in this regards. The area of study is located between 49°, 35' and 52°, 33' E and between 27°, 21' and 30°, 02' N in depth of 7 to 78 in. Study were conducted diuring August 1998, September 1999. Samples were taken during 3 sea cruises from 70 bottom trawl net. All sharks and batoid fishes were identified based on biometric specifications (weight, total, length and sexuality for both group and extra biometric specifications, disc width, disc length, and tail length only for, batoid fishes). The 1140 specimens of batoid fishes identified belonged to 6 families, and 18 species. 3 new species were identified, they are Himantura sp.1 and Himantura sp.2 belonged to Dasyatidae family and Rhinobatos sp. belonged to Rhinobatidae Familiy. It needs more works and more adaquate ducuments for cl.earfing scientific names of these species. The 275 specimens of sharks identified belonged to 6 families and 10 species. Chiloscyllium sp. belonged to Hemiscylliidae, family as a new species was identified.

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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

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Annual cycle of gonad development and spawning in pearl oyster, Pinctada ficata (Gould) in Nakhiloo, Northeast Persian Gulf, was investigated over two years from August 1994 to June 1996. Gonadal condition was assessed by staging criteria to describe gametogenic development from histological preparations of randomly collected individuals of all sizes. A bimodal gametogenic pattern with summer and autumn spawning periods was evident throughout the study. Gametogensis commenced in November-December which proceeded by major gonadal maturation during February-April. Summer spawning was observed from April to July with major spawning at the latter end. During spawning peak in July, low level of gametogensis was noticed. Gametogenic activity was picked up again in August-September which proceeded by autumn spawning from September to December. Towards the end of spawning season, incidence of gonadal inactivation increased. Minimum level of gonadal activity was observed in November. Temperature regime appears to have influential role in regulation of gametogenic and spawning processes. Gonadal development and spawning trends were similar in both sexes. P. radiaata was found to be protandrous hermaphrodite which matured as a male at shell height greater than 20 mm. Biseivality was uncommon and the sex ratio was about 1:1. Ultrastructure of gametes were investigated in the Pictada fucata (Gould). "Auxiliary cells" closely accociated with developing oocytes were observed. Each oocyte seems to be associated with only one secretory cell. which is characterized by an abundant rough endoplasmic reticulum at the onset of vitellogenesis. Contact between this cell and a developing oocytes is maintained by a desmosome-like junction which can be observed when the vitelline coat is formed. these "auxiliary or nursing cells" seem to play a tropic role in vitellogenesis, and may be involved in the formation of the vitelline coat of the oocytes. Oocytic degeneration is observed in this species, it is a continuous phenomenon of varing intensity throughout the year. The ultrastructural changes resulting in lysis of the oocyte are described. Mature spermatozoa consist of a broad, cap-shaped acrosomal vesicle, subacrosomal material, a round nucleus, two triplet substructure centrioles surrounded by four spherical mitochondria, and a flagellum anchored to the distal centriole and plasma membrane. Spermatozoa of Plucata closley resemble to those of other investigated Pteriidae. Changes in proximate composition of soft tissue and gonadal cycle of Pinctada fucata was studied. Mobilization and utilization of stored reserves are apparent during gametogenesis and gonadal maturation. Protein reserves are utilized during spermatogenesis while reserved carbohydrates form the main energy donor in oogenesis. The role of lipid as am.: energy reserve is second to that of carbohydrate.

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The ribbon fishes ‘of the family Trichiuridac are represented as one of the most important food resources in Indian ocean. High density of the dominant species of ribbon fish (Trichiurus lepturus) in Oman sea and the 'Tillable catch in last yeas (more than 7000 tones per year) makes a trust area for studing their population biolog and stock assessment. As our knowledge on reproductive biology of this species has an important role on their fisheries management, as well as conservation of this stock from decline or over fishing, this research was held to determine some aspects of reproductive physiology of ribbon fish and the effects of environmental factors in gonadal cycle. The goals of the present thesis is to determine some aspects of reproductive physiology such as gonadosomatic index (GSI) , hepatosomatic index (HSI), condition factor (Ko, fecundity, sex ratio, size at first maturity, size at maturity (LM5O) and their relative hormonal & biochemical fluctuations. In this regards annual variation of sex hormones ic. estradiol 17-B, progestron, cortisol, testostrone and gonadotropins FSH (GTH-I) , LH (GTH-ll)I were measured ; gonadal histological studies were done by light & electron micrography. The research was carried out from April 1995 to January 19% in Ras Nleidani in the north part of Oman sea, and the environmental factors such as temperature, salinity, oxygen, rainfall and pH were measured. The effects of these parameters on reproductive cycle and hormonal fluctuationswere discussed by using correlation and principle component analysis (PCA). Female Ribbon fish reproductive strategy shows the same paterns of nonguarder marine teleosts. T. lepturus has more than one spawning season (existance of egges in different size in each month) and therfore it must have asynchronous ovaries and belong to continious spawners. GSI and HSI are good evidences for this type of reproductive patern. The testis of the lobular type , which is typical of most teleosts , is composed of numerous lobules which are separated from each other by a thin layer of fibrous connective tissue. GSI fluctuations revealed prolong- spawning time in males. There is significant increase in 17-13 estradiol. progestrone , cortisol and gonadotropins with maturity and prespawning period of female T lepturus. Plasma concentration of E2 and GTH II incresaed along with water temperature increasing (3300).. Spawning was observed from Nov. 1995 to Apr. 1996 in this species. Progestrone increased significantly with increasing rainfall in this season (P<0.01). Plasma cortisol levels increased with maturation and vitelpgenesis and also with the peak of spawning. From lenght-weight frequency and size distribution in each age groups and also minimum size at first maturity (52a cm) it would he concluded that T. lepturus must be matured at 2 years of age. Serum cholestrol and triglicerides significantly increased when maturation occured in this species. The relationship between alkaline phosphatase activity and hormonal fluctuations with maturity and vitelogenesis were discussed. Proximate compostion (muscle) shows significant variation with spawning period and maturity. Absolute individual fecundity (17420-159150) increased with body length and weight. Ultrastructural observations show dramatic variation in cell membrane (0ocyte membrane), yolk vesicles and, nucleolus dispersal in relation to maturity stages. fluctuations of gonadal hormones were discused in relation with vitelogenesis. Testosterone increased in males from Nov: to Mar. due to environmental impacts and spawning time. Sex ratio in different depth (10-40 m ,80-110 m) shows significnt differences in this ratio for two depths. In 10-40 m depth female shows dominant abundance to male in each months that may be due to their reproductive migration behaviour. The effects of temperature photoperiod and rainfall to maturity and spawning were discussed. According to -pawning period of T. leptunts in our sampling area it could be suggested that ribbon fish fi,theries must be restricted in the peak of spawning seasons (Feb. to Mar.) and in the spawning grounds (under 40 m depths). Other suggestions for population conservation have been mentioned.

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The population density, distribution, diversity and secondry production of macrobenthic fauna of the inner Chahbahar Bay were studied through bi-monthly sampling from April 1995 to March 1996. Samples were collected from water near the bottom and sediment at 14 stations inside the Bay and one reference station located outside at the entrance to the Bay. The environmental parameters Such as temperature, water depth, salinity, pH and dissolved oxygen as well as percentage silt-clay and total organic matter of the sediment were measured. The faunal population density and their distribution is discussed in relation to the environmental changes. results obtained indicated both spatial and temporal heterogeneity in faunal distribution of the Chahbahar Bay. The total of 18 groups of macrofauna were identified in all samples. Amphipods formed the dominant group (21%) followed by polychaetes (19%), gastropods (15.7%) bivalves (10.6%) and all other groups (33.7%). Seasonal changes in faunal density is shown in relation to Indian Ocean southwest monsoon,the result of which indicated lower population density during monsoon (June to September) than that of the premonsoon (February to May) and post monsoon (October to January) periods. The numerical abundance of macrobenthos varied from 10260.m2 before monsoon to 5190 m2 during monsoon season. Three dominant groups of macrofauna including polychaetes, gastropods, and bivalves were identified in all collected samples. Indices of diversity, richness and evenness were calculated for these three dominant groups. The Shannon-Weaver information index was used to describe the spatially and temporally variation in diversity of these three major faunal groups. The results exhibited lower faunal diversity during monsoon period. The annual production of two dominant macrofauna species including a species of bivalve, Nuculana acuta and a species of Cephalochordata, Branchiostoma lanceolatum were measured by using age group determination. Furthermore the mean biomass and total annual production of macrobenthic fauna were estimated for the whole studied area. The potential yield of demersal fishery resources (fish and crustacean) then estimated and worked out to be 15360 tons/year asuming 10% ecological efficiency of hypothetical pyramid from 3rd to 4th marine trophic level. Accordingly the annual exploitable demersal fishery resources for the entire Chahbahar Bay was estimated to be 7600 to 8500 tons/year by taking 50 to 55% of the total estimated potential in to account.

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To investigation of the toxic effects of atrazine on newly hatched larvae and releasing age fry of the Caspian Kutum, Rutilus frisii kutum, the 96h LC50 was determined as 18.53 ppm and 24.95 ppm, respectively. Newly hatched larvae were exposed to three sublethal concentrations of atrazine (1/2LC50, 1/4LC50 and 1/8LC50) for 7 days. Different histopathological alterations were observed in fins and integument, gills, Kidney, digestive system, liver and the brain of the exposed larvae. Fry’s were exposed to one sublethal concentration of atrazine (1/2LC50) for four days, and like the larvae’s, many histopathological alterations were observed in fins and integument, gills, Kidney, digestive system, liver and the brain of the exposed fry’s, too. Also, measurements of the body ions: Na+, K+, Ca2+, Mg2+ and Cl- in atrazine exposed larvae and fry’s compare to control groups showed that atrazine is changed the body ions composition. No significant differences were found in length growth rate, weight growth rate and the condition factor of the atrazine exposed larvae and fry. Immunohistochemical localization of the Na+, K+-ATPase in integumentary and gill ionocytes, showed no differences in dispersion pattern of the ionocytes in atrazine exposed larvae and fry, compare to control group. Measuring the dimensions of the ionocytes and counting the ionocytes showed that atrazine is affecting on ionocytes by mild increasing in size and mild decreasing in number. Ultrastructural studies, using SEM and TEM, showed that atrazine have significant effects on cellular and subcellular properties. It caused necrosis in surface of the pavement cells in branchial epithelium, necrosis in endoplasmic reticulum of the ionocytes and changed the shape of the mitochondria in these cells. Results showed that sublethal concentrations of atrazine were very toxic to larvae and fry of the Rutilus frisii kutum, and at these levels can made some serious histopathological alterations in their tissues. Related to the severe histopathological alterations in osmoregulatory organs, like gill, kidney and digestive system, and the alterations in the body ion composition, it could be concluded that atrazine could interfere with the osmoregulation process of the Rutilus frisii kutum at the early stages of the life history.