17 research outputs found
The effect of cations on sperm motility performance and fertilizing ability of silver carp Hypophtalmychtis molitrix
The objective of the study was to investigate the effect of saline solution containing cations (Na+, K+, Ca+2, Mg+2) on sperm motility performance (duration of sperm motility and percentage of motile spermatozoa) and fertilizing capacity of sperm (fertilization rate, hatching rate, larvae length during hatching, larvae length during active feeding and survival rate) in silver carp. The results suggested that solutions containing ions did not improve the duration of sperm motility. The same was observed for the percentage of motile spermatozoa. Fertilization rate influenced by solutions containing Ca+2, and other ions could not affect this parameter. The results showed that hatching rate was higher in solutions containing 99 mEq/L NaCl, 2 mEq/L MgCl2 and 2, 4 mEq/L CaCl2 respectively. Also, survival rate was higher in the solution containing 2 mEq/L MgCl2 and 36 mg/dL KCl respectively.With regard to the obtained results, it was concluded that using appropriate activation medium can improve quality of fish sperm and subsequently increases artificial reproduction performance
Determination of pollution condition in Babolroud River from viewpoint of pesticides and agrochemicals fertilizers
Babolroud River is one of the important rivers for fisheries and environmental aspect that locared in center part of Mazandaran province. The river has a span of 92 km starting from Albourz mountainous and end up at the southern part of Caspian Sea. This study was done for five months (3rd Feb. through 5th July, 2008) for the better understanding of pollution situation such as organophosphorous, organochlorine pesticides and agrochemical fertilizer that drainage from paddy fields and horticultures to the river. A total of three main sites for pesticides and plus five sub-sites for drainage were selected for observation in three different regions of the river (mountainous, plain and estuary). The organochlorine and organophosphorous pesticides measured by GC (ECD and TSD detectors) with US-EPA (508) and AOAC procedure and agrochemical fertilizer parameters were measured by ASTM method. The maximum concentrations of aldrin, lindane, heptachlor epoxyde, DDE and β- BHC (period 1), δ- BHC and endrin (peiod 2), heptachlor and DDT (period 3), α- BHC (period 3 & 4), dieldrin (period 4) were 6.02, 0.85, 0.51, 0.50, 0.22, 0.35, 0.23, 0.50, 0.46, 0.19 and 0.16 µg/l, respectively. The maximum concentrations of four components of organophosphorous such as Diazinon and Chlorpyrifos (period 1), Malathion (period 2), Azinphos methyl (period 3) were 1.36, 0.46, 0.44 and 2.56 µg/l, respectively. The maximum amounts of tree components of parameters of agrochemichals fertilizers indictor such as total nitrogen (period 2, sub-site 5), total phosphorus and orthophosphate (period 4, sub-site 5) and organo-phosphorus (period 3, sub-site 4) were 5990, 1290, 1220 and 336 µg/l, respectively. The maximum concentrations of organochlorine pesticides components in sediments of the river such as lindane (period 2, site 2), δ- BHC (period 1 site 3), α- endosulfan (period 1, site 2), endrin and heptachlor epoxide (period 2, site 2) and DDE (period 2, site 1) were 0.99 0.54, 0.29, 0.19 and 0.19 µg/l, respectively. The maximum concentrations of organochlorine pesticides components in fish tissue of the river such as endosulfan sulfate, lindane, endrin, δ- BHC and DDE were 0.32, 0.29 0.27, 0.25 and 0.21 µg/l, respectively
Study on macrobenthic communities in the range of fish cage-culture area (before breeding) in the southern Caspian Sea (Mazandaran coast-Kelarabad)
The abundance and biomass of benthic macroinvertebrates were studied in the place of fish cage culture in southern coasts of Caspian sea (Mazandaran waters- kelarabad). The goal of this study was to consider of fish cage culture effects on the abundance and biomass of benthic macroinvertebrates. The sampling was carried out in 3 stations in depth of 20 meter of Kelarabad waters monthly. In this study 7 species were identified belonged to 5 genus of 4 family. Totally 23442 sample of benthic invertebrates were counted that the lowest and highest abundance were in station 1(23.4%) and station 2(46.8%) respectively. The results of stations study showed that the highest abundance and biomass were in stations 2 and 3 with the average of 646 ± 1230.4 n/m^2 and 0.526 ± 1.001 gr/m^2 respectively. This coulld be respectively dependant to not settling of cage (witness station) and appearance of Cerastoderma glaucum because of its large body in station 1. The difference of abundance and biomass between different stations was not significant (p ›0.05). The study on abundance and biomass in different seasons showed that the highest abundance in autumn with the avarage of 888.13 ± 1371.58 n/m^2 belonged to Strblospio gynobranchiata and the highest biomass belonged to C. glaucum which was because of appearance of not native species of polychaeta and also the species with shell covering from bivalvia. The results showed that the specie of S. gynobranchiata from polychaeta including 93.3% of abundance was the dominant specie that could be related to appropriate ecological conditions for living and high adaptability. It was concluded that the abundance and biomass of benthic macroinvertebrates in station 1 was lower than other stations which was related to fish cage culture activity and its effects on benthic macroinvertebrates. So it is suggested that each mariculture activity in southern coasts of Caspian Sea should be carried out with regarding to environmental considerations and performance of comparative evaluation project of environmental effects
Investigation on probable viral agents associated with grass carp and silver carp mortality in Guilan province
Warm water aquaculture development along with import of eyed eggs, Broodstocks and ornamental fish also transferring of fingerlings and broodstocks from one province to another one has led to spreading of some unwanted diseases. According to the Gilan Fisheries Department report, mortality rate of silver carp(Hypophthalmichthys molitrix) in the summer of 2010 caused losing of silver carp production more than 1162 tons which was valued over than twenty-three milion rials that was increased to about 40 million rials in 1391. Also grass carp had a less mortality rate in some farms. Observed symptoms and severity of losses increased the probability of viral diseases such as spring viremia of carp, koi herpes virus and grass carp reovirus. In this research, totally 411 silver carp and grass carp with 5 to 2300 gram weight from 83 farms were sampled during 2011-2012. Clinical symptoms was different in various farms and subcutaneous hemorrhages on the flanks, red fin base or total fin and Red belly and operculum, mild exophthalmia, hemorrhaging in the abdominal cavity (yellow, transparent or red fluid) and petechial haemorrhages of skin and viscera and Ascites in abdominal cavity and some silver carps and grass carps were observed with palied liver and gill. In some cases swelling muscle was observed in Silver carp. Several fries with the severe emaciation were observed. Difference between clinical symptoms can indicate the presence of different causes of mortality in different farms. Various water colors from completely transparent to dark green, yellow or slightly brown observed in different pool, which shows the difference in overall culture management including water quality management. The minimum Water turbidity using secchi disk was 40 centimeters to one meter page in the fields. Source semi-deep wells or deep pools that were used as water source. Average water temperature, oxygen and pH in fileds 26/5-31 °C , 4/3-5/7 mg / L and 7/4-9/38. In order to virological surveys, sampling of internal organs, including kidneys, and spleen were done.and Homogeneous target tissues after spending 0/45 micron filter on EPC and BF2 cell line were inoculated to observe cell damage(CPE) in case of confirmation of antibody detection methods brilliant, RT-PCR and PCR done. In cell culture examination, a kind of cell damage (CPE-like changes) was observed after inoculating of 3 samples of Silver carp those were suspected to SVC, but in the second and third passages there were no sign of cell damage. It may be because of toxic effect of tissue filtrate on the cell monolayer. Concerning sample of Grass carp on two EPC and BF2 cells no evidence of cell damage was found. In indirect fluorescent antibody test, 72 hours after inoculation of tissues filtrates of of silver carp and grass carp samples on EPC, no positive reaction was observed. PCR and RT-PCR tests using specific primer pairs were done to test all of the silver carp and grass carp samples for SVC and KHV diseases Also for GCRV in grass carp samples. In addition, simultaneously commercial PCR kits applied for testing of SVC and KHV (IQ2000. Taiwan). The results of PCR and RT-PCR tests showed no evidence of robdovirus Carpio and grass carp reovirus RNA and no sign of koi herpesvirus DNA in tested samples. In conventional PCR and RT-PCR tests Using specific primer pairs none of positive bands related to SVCV(470 bp) and GCRV(292bp, 697bp and 320bp) were not confirmed in the tested samples. Also in electrophoresis of PCR products using IQ2000 kit revealed 471 bp and 640 bp negative bands in all samples and the positive bands were not observed. For confirmation of the results, three suspected samples were sent to Europe Union Reference Laboratory and none of mentioned diseases were confirmed. Simultaneously bacteriolocical examination applied for 26 using blood agar. In bacterial culture and related analyzes 6 isolates of Pseudomonas and 21isolates of Aeromonas hydrophila were detected from 26 farms while no virus was confirmed in the same samples. Based on the results of cell culture, PCR, RT-PCR and IFAT tests no one of SVCV, KHV and GCRV viruses were confirmed in tested samples. Therefore, the etiological reason of the mortalities in the tested farms was not viral diseases and should be prevent and control by biosecurity and health management in the farms
Determination of suitable size of Rutilus frisii kutum for releasing by evaluation of osmotic regulation ability
The study was done in Nutrition and Live Food Station was located in Bandar Anzali Ghaziyan. Juveniles weighted average 0.5, 1, 2.5, 5, 10, 15 and 20 g were randomly selected in three water conditions with a salinity of 11 ppt (Caspian sea water), water 7 ppt and freshwater (with three replicates per group) were included. At intervals of 0, 3, 6, 12, 24, 72, 168, 240 hours, blood samples were heparinized capillary tubes by caudal juveniles and ion concentrations Mg, Ca,Cl using the spectrophotometer and sodium and potassium ions with Flaym photometry (flame photometric), the osmotic pressure of blood plasma by osmometer and cortisol levels were measured by RIA method. To study the microstructure of gill and kidney tissue for each treatment , tissue samples by classical histological methods and stained with hematoxylin - eosin slides were prepared. The frequency and location of the enzyme Na^+, K^+ - ATPase and chloride cells with immunohistochemical localization was performed. Studies micrometric gill chloride cells and renal glomerular networks by software Image tool (version 2.0) was performed. Measurement of enzyme Na^+, K^+-ATPase, by Zaugg (1982) method was conducted. Data analyzed by one-way ANOVA (Oneway ANOVA) with Tukey's test was performed. Overall, the results of measuring ions and osmotic pressure on the tenth day of treatment, the osmotic potential juveniles 2.5, 5, 10, 20 gr in Caspian sea water and all groups except the 0.5 in water of 7 ppt confirmed. But in case of unfavorable conditions for the release in estuaries river and river, fish with weight 1 to 3 release directly to beach (where the salinity is 7 grams per liter) and fishes with weight from 10 to 20 gr to sea. Although suitable river conditions necessary condition for release of juveniles in riverine areas to adaptation juveniles occur gradually
Mineralogical and geochemical evolution of the Bidgol bauxite deposit, Zagros Mountain Belt, Iran: Implications for ore genesis, rare earth elements fractionation and parental affinity
The present study focuses on the Late Cretaceous Bidgol bauxite deposit in the Zagros Simply Fold Belt, SW Iran. The orebody is located in the eroded major NW–SE trending Koh-e-Hosseyn anticline and hosted as discontinuous stratified layers and lenses within the upper member of the Cenomanian–Turonian Sarvak Formation. Detailed mineralogical analysis reveals that diaspore, hematite, goethite, anatase, clinochlore, chamosite, and calcite are the major mineral components accompanied by minor amounts of detrital and REE-bearing minerals such as rutile, zircon and parisite. The ore texture suggest that the bauxite material has an authigenic origin but in some parts it has been transported short distances from a primary in situ environment and redeposited in karstic depressions. The spheroidal pisolites of the Bidgol bauxite formed under conditions of low water activity, favouring the formation of large diaspore cores and a single dry-to-wet climatic fluctuation. The mass change calculations relative to the immobile element Ti show that elements such as Si, Fe, Mg, K, Na and Sr are leached out of the weathered system; Al, Ni, Zr, Ga, Cr and Ba are concentrated in the residual system; and Hf, Ta, Co, Rb, Cs, Be, and U are relatively immobile during the bauxitisation processes. The Nb, Th, Y, V, Sc, Sn and ΣREE are relatively immobile in the initial stage of bauxitisation processes in the bauxite ores, but were slightly mobile at the later stage of bauxitisation. Geochemical data reveal progressive enrichment of the REE and intense LREE/HREE fractionation toward the lower parts of the bauxite profile. Cerium behaves differently from the other REEs (especially LREE) and show positive anomalies in the upper horizons that gradually become negative in the deeper parts of the profile. The distribution and fractionation of trace elements and REEs during the bauxitisation process in the Bidgol deposit are mainly controlled by the presence of REE-bearing minerals, fluctuations in soil solution pH, REE ionization potential and the presence of bicarbonates or organic matter. Geochemical analyses confirm a protolith contribution from the bedrock argillaceous limestone and suggest that the source material for the Bidgol bauxite was provided from a siliciclastic material derived from a continental margin. The mid-Turonian uplift led to the formation of karstic topography, rubbly breccia and a layer of ferruginous–argillaceous debris that was affected by lateritic weathering under humid tropical climate. Subsequently, mobile elements are removed from the profiles, while Al, Fe and Ti are enriched, resulting in the formation of the pristine bauxite materials. When the platform subsided into the water again, the pristine bauxitic materials were partly converted to bauxite. During the exposure of bauxite orebodies on the limbs and crests of anticlines and subsequent eroding and accumulation in the karstic depressions during folding and faulting in Oligocene–Miocene, important factors such as intensity of the weathering, drainage and floating flow may have improved the qualities of the bauxite ores
Spread of West Nile virus in Iran: a cross-sectional serosurvey in equines, 2008-2009
International audienceWe report the first large-scale serosurvey for West Nile virus (WNV) conducted in the equine population in Iran. Blood samples were obtained in 2008–2009 from 1054 equines collected from 260 districts located in 27 provinces. The overall seroprevalence rate for WNV neutralizing antibodies was 23.7%. Marked geographical variations were observed as province-specific seroprevalence rates ranged from 1% to 88%, the highest values being observed in the southern and western parts of the country. The presence of IgM-positive animals (n=9) indicated a recent circulation of WNV in several provinces. Logistic modelling confirmed this result with a significant effect of age on seropositivity. This study revealed extensive circulation of WNV in Iran particularly in southwestern provinces where the virus probably circulates every year
Evidences for confirmation of an epidemic in acute respiratory syndrome crisis among residents of Ahwaz November 2013
Background and Objectives: Ahvaz has become one of the most polluted cities in the world. Only on 11 November 2013, over one thousand residents in Khuzestan Province attended the nearest health center with severe symptoms, particularly shortness of breath, cough, wheezing, and high blood pressure. During a week, more than 7 thousand patients were registered with this syndrome. This study was conducted to investigate the evidence for the confirmation of an epidemic in acute respiratory syndrome among the residents of Ahwaz in November 2013. Methods: In this cross-sectional study, we evaluated the data of the use of drugs related to acute respiratory attacks from November 2008 to 2013 in Ahvaz. Then, we conducted a descriptive study on the general population. The sample size was 120 and the study participants included different segments of the general population. The data collection tool was a researcher-made questionnaire and the data were analyzed using SPSS.18. Results: The use of the respiratory drugs increased from 2008 to 2013. The drug consumption was markedly higher in November 2013. In the study of the general population, 93 of the participants declared that they had never seen a similar event, and 92.5 mentioned that they had never heard of a similar occurrence. Conclusion: Due to the significant increase in respiratory medicine in November 2013 and the unexpected nature of the event, an epidemic seems to be obvious. © 2016, Iranian Epidemiological Association. All rights reserved