JOURNAL OF MARINE SCIENCES AND TECHNOLOGY
Year:2011 | Volume:10 | Issue:2|Papers Count:11

In this study the effects of two catch methods (gillnet and beachseine) were investigated on some spermatological parameters of Kutum brood stock. For this purpose 8 adult male caught by gill net and beach seine were stripped by applying slight pressure to abdomen section of fishes and sperm samples were transferred to laboratory in ice box for spermatology analysis. Semen volume was measured by scaled syringes and sperm movement duration by faze-contrast microscope. spermatocrit was determined by haematocrit reader. The results showed significant (P<0.05) differences in spermatocrit levels between fishes that were captured by gillnet and beach seine, but no significant (P>0.05) differences observed in semen volume and sperm movement duration between the two methods. The results showed that fishes captured by gillnet had more positive index in comparison to fishes captured by beach seine.

In order to understand the extent of heavy metals contamination in sediments and rock oyster Saccostrea cucullata, of Chabahar intertidal zone, samples of sediment and oyster were collected from 5 different stations namely Guatr, Beris, Ramin, Shahid Beheshti and Tiss during low tide. Sediment and tissue samples were acid digested and heavy metals content of the samples were analyzed. Results showed that Cu, Pb and Ni concentration in the sediment samples was 15.87-16.96, 10.98-15.79 and 12.39-17.10 mg/g, respectively. Heavy metals concentration in soft tissues of oyster was 84.96-289.93, 3.83-5.26 and 6.05-7.19 mg/g for Cu, Pb and Ni, respectively. Similarly, Cu, Pb and Ni concentration in shell ranged between 13.83-6.67, 11.32-14.93 and 5.97-7.97 mg/g, respectively. No significant difference was found between Cu and Ni concentrations in sediment samples. It is suggested that metals accumulation in different oyster tissues was related to their essentiality for oyster. Heavy metals concentration in oyster and sediment was found to fall within the range of some available standards, indicating that metals contamination does not seems to be problematic in the area.

total of 311 specimens were collected from November 2006 to October 2007. We estimated Population parameters from length frequency data. These cases consist of the von Bertalanffy growth parameters and mortality, as well as exploitation rate. The result indicated that pickhandle barracuda had L¥=109.21 cm total length, K=0.37 and theoretical age at zero length, t0=-0.5 The total mortality rate (Z) was estimated to be 1.91, the fishing mortality rate (F) and the natural mortality (M) were 1.30 and 0.61, respectively. The exploitation rate (E) was 0.68. The exploitation rate indicated that the stockis in high pressure of catch and overexploited.

The effect of specific nutrients on Salmo trutta caspius intestinal variation are practically unknown. The purpose of this work was to study the effects of different levels (0, 0.25 and 0.5%) of dietary nucleotide that added in control meal, on several segment of intestinal structure of Caspian salmon juvenile with average 12.26±0.001 g weight (average length 11.1±0.002). This trial was achieved in fiber glass 300 liter fresh water tank with 35 fish in each one. Fish cultured in 8 weeks and experiment has done on fish with average 26 g weight.6 fish from each treatment captured, sacrificed and immediately gastro intestinal tract fixed by immersion into Bouin solution for histology. Then histological sections of 4 mm obtained, stained with Hematoxiline-Fushin and investigated. Results indicate that in duodenum nucleotide has a significantly (P<0.05) effects on villi length, thickness of muscle and sub mucosa. This treatment have been showed maximum of villi length and tickness of muscle. Similar results have been showed in ileum and jejunum. In this segments nucleotide have a significantly (P<0.05) effects on maturation and growth of villi length, muscle and submucosa.

The Mendelian Inheritance of produced hybrids from Chalcalburnus chalcoides and Vimba vimba persa was investigated using Microsatellite Markers. Genomic DNA from the produced larva and also small piece of dorsal and pectoral fin of their parents were extracted by Phenol-Chlorophorm method and PCR reaction was accomplished.10 loci were amplified, in which 7 of them were amplified with reasonable polymorphism and 3 were monomorphism.In order to study the segregation of the produced F1 hybrids from female Chalcalburnus chalcoides and male Vimba vimba persa, seven loci (LCO3, LCO1, Lid11, Rru2, Z1-2, Z7-8, Z9-10) were used.According to the results it showed that parents and F1 larva's allelic distributionwere almost segregated based on Mendelian inheritance in 7 loci. The present study showed that Microsatellite markers are useful marker in study of inheritance.

In this research, were used from Bacillus licheniformis and Bacillus subtilis (spore-forming gram positive bacteria) for single cell protein production from tuna fish viscera (Thannus tonggol). Examination was done in two laboratory and fermentor scales. The used fermentor was Continues Stirred Tank Reactor (CSTR). Influence of several parameters such as pH, temperature, rpm, and fermentation time was evaluated on SCP production process. The result showed that value of SCP was 30- 45 g/l of aliquot substrate. Growth of isolates in 35oC and pH=6.9 were more than 32oC pH=6.5. Time fermentation in lab and fermentor scales was 54h and 21h respectively. Production of SCP in rpm=600 in fermentor scale was more than rpm=300. With complementary examination, can be used from SCP produced from tuna viscera, as probiotic, in fish feed.

Water treatment in recirculation aquaculture systems (RAS) is one of the main methods in water quality management. In organic Ion exchange materials are used only for ammonia adsorption in rearing systems. Zeolites have negative charge in their surfaces and this property capable them to remove cations and metal ions. At this study by using a cationic surfactant (Tetradecyltrimethylamonium bromide) clinoptilolite surface for removing nitrogenous compound is changed. Studied zeolite was analysed by XRD and XRF. Results indicated that Heulandit was the main element in the sample. Experiment was done at three replicates under environmental conditions (temperature (10, 15 and 20) and pH (6, 6.5, 7, 7.5 and 8)). Results indicated that environmental factors influenced absorption capacity. Results showed that increased in temperature have significant effect on nitrate and nitrite removal by SMZ (P<0.05).Temperature cause Increasing in anion mobility and finally anion adsorption. pH have significant effect on nitrate adsorption (P<0.05) while any regular trend didn't observe about nitrite. Increasing pH cause increase in ionization degree and adsorption. Results indicated that other factor such as anion concentration, existing other anions and counter ions impressed adsorption.

Dry Bulk market is the largest sector of world shipping market. The analysis of this market and the assessment of dry bulk freight rate, market behavior, policy making in this field, transportation policies and fleet development, and also research in dry bulk shipping industry is inevitable.The main aim of this study is to analyze and forecast the future of dry bulk freight market in 2011 and 2012.Since the shipping industry is known to be a volatile industry; therefore, understanding the characteristics of this market and forecasting its volatilities have been of prime interest in operational and financial decision makings. To achieve this aim, linear regression, multiple regression and time series analyses (winer's exponential smoothing) methods is used. Results of the study show that the Baltic Dry Index in 2011 and 2012 may decrease in relation to 2010, but this drop in 2011 will be drastic and in 2012 modest.

Development of modern energies is one of the most important issues that all countries have focused on and have tried to find a new model in that respect. This study investigates various methods of estimating energies that are produced by wave and then it concludes that the best method is spectrum analysis using Fourier analysis. Using available data of year 1998 in Chabahar and applying a program which is produced in MATLAB environment, rate of producible energy in year 1998 is equal to 6.9 Kwh/m2 and producible power of waves has been estimated to be 3.9 Kw/m2 with the lowest rate of energy observed in winter and the highest rate of wave energy in summer. Probable cause of this phenomenon could be seasonal winds that blow in summer. According to the flowmetry report done by Ports and Maritime Organization in Chabahar, in Aw1 Station has divided its 9-meter distance below water surface into 7 cells, therefore, with considering 1×1m channels and assuming that flow in each channel has been changed steadily, tide flow energy has been estimated and average energy of Chabahar station has been obtained equal to 0.12 w/m2 within two weeks. In the second way, using program written in MATLAB environment and calculating the surface under the chart, tide energy has been calculated equal to 0.19w/ m2. According to the obtained results, producible energy of tidal current in Chabahar Gulf is very low and it is not economical.