Sturgeon fishing in common waters at the Caspian Sea

Caspian Sea is the largest enclosed sea of the world Up to 10 miles from the coastal line is included in the EEZ after which common water zone starts. The investigation was carried out in order to determine sturgeon stocks in the common waters of southeastern Caspian Sea and propose suitable fishing methods. The study lasted for one year during which fishing data, species composition, age composition, maturity stages and other parameters relating to sturgeon squired from common and exclusive waters and compared with each other. The results showed greater density of immature and smaller sturgeons in the common waters. Also south eastern common waters of the Caspian Sea was found unsuitable for fishing of sturgeons

Stock assessment of the Caspian Sea bony fishes

The project was carried out in the southern coastal areas of the Caspian Sea measuring length, weight and age of more than 30,000 fishes together with recording of relevant fishing information. Also age-weight, length-weight and age-length relationships was calculated for the separate species and total and natural mortality rates was determined. Furthermore biomass assays. Cohort analysis, and stock assessment of different fish species was conducted and maximum sustainable yield determined. The results showed that nearly 90% of the catch is composed of Rutilus frisii kutum, Mugil saliens and Mugil auratus. Total biomass of the mentioned fishes was estimated to be. 24000, 7000 and 2400 tones with the, maximum sustainable yield being 7000, 2900 and 960 ton respectively

BIOLOGICAL PARAMETERS AND FISHERIES INDICES OF BELUGA STURGEON Huso Huso IN THE SOUTHERN CASPIAN SEA

Postoji značajan nedostatak podataka o biološkim parametrima morune Huso huso, najveće ribe u Kaspijskom moru. Ovim istraživanjem određivala se dob i indeksi rasta morune u svrhu procjene stanja njenog fonda u južnom Kaspijskom bazenu Irana od 1990. do 2011. Duljina vilice kretala se u rasponu između 113-420 cm, a masa od 8,0 do 725,0 kg. Parametri rasta bili su L∞ = 440 cm, K = 0,027 godina−1, t0 = - 5,8 godina. Dob pri prvom ulovu (tc) bila je 13,1 godina. Podaci o dugoročnoj strukturi dobi morune ukazali su na dob do 63 godine, a jedinke u dobi od 12-19 godina sačinjavale su 76,7% ukupnog ulova. Dužina generacije bila je 33 godine. Vrijednosti KF indeksa bile su blizu 1 ili > 1, što ukazuje da je moruna u povoljnom kondicijskom stanju u južnom Kaspijskom moru. Raspodjela vrijednosti dužine morune ukazala je kako 24,2% ulova čine juvenilni primjerci. Natemelju dobne strukture i dobi pri spolnom sazrijevanju, novačenje i prekomjerni ribolov utjecali su na zalihe morune. Ovim se, u budućim ribarstvenim politikama, preporuća povećati dužinu ili starost morune pri ribolovu. Mega-mrijesni primjerci morune su predstavljali 4,4% ulovljene ribe, što ukazuje na neujednačenu strukturu populacije.There is a significant lack of data for the biological parameters of beluga or great sturgeon, the largest fish in the Caspian Sea. The age, growth and fisheries indices for the stock status of beluga was investigated in the south Caspian Basin of Iran between 1990 and 2011. Fork lengths ranged between 113-420 cm and weights from 8.0 to 725.0 kg. The growth parameters were L∞ = 440 cm, K = 0.027 year−1, t = − 5.8 years. The age at first capture0(tc) was 13.1 years. The long-term age composition data showed age up to 63 years, and the ages 12-19 years comprised 76.7% of the total catch. The generation length was 33 years. The values of “KF” were close to 1 or >1, indicating that beluga sturgeon is in a favorable condition in the southern Caspian Sea. The length distribution showed that 24.2% of the catch is comprised of juveniles. Based on the age structure and age at first maturity, recruitment and growth overfishing occurred in beluga stocks. Therefore, increased length or age at first capture in future fishery policies should be implemented. The mega-spawners represented 4.4% of the fish captured and revealed an unhealthy population structure

Development of disomic single-locus DNA microsatellite markers for Persian sturgeon (Acipenser persicus) from the Caspian Sea

Understanding the scale at which wild stocks of Persian sturgeon (Acipenser persicus) are genetically discrete is necessary for effective management of this commercially important species. Disomic DNA microsatellite markers are among the best tools for determining stock structure in fishes. As all sturgeon species have a polyploid ancestry of all sturgeons, most gene loci exhibit more than two alleles per individual, limiting the use of powerful analytical methods that commonly assume disomic inheritance. We scored products from 38 sets of microsatellite primers developed in lake (Acipenser fulvescens) and Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) to determine whether they would amplify disomic loci in Persian sturgeon. Samples of 45 individuals were detected.Thirty six loci (95%) were amplified successfully in Persian sturgeon. We identified a single monomorphic locus, 12 disomic, 19 tetrasomic, three octosomic, and one locus that was ambiguous. This is the first report on development of disomic single-locus DNA microsatellite markers in Persian sturgeon. These loci could be used to characterize variation in geographically discrete populations of the Persian sturgeon in their native ecosystem including in the Caspian Sea

Characterization and isolation of microsatellite in Persian sturgeon (Acipenser persicus, Borodine, 1897)

In order to have a sustainable management on Persian sturgeon (Acipenser persicus) as a highly commercial species in the South Caspian Sea, we need to identify its population structure and the level as well as its conservation status in their natural habitat. To develop a conservation program for this all Caspian Sea' sturgeon species it requires knowledge of its genetic diversity using reliable molecular marker to study population genetic structure. For these purposes, an enriched library was prepared based on a modified biotin-capture method. Approximately 1800 positive clones were screened for microsatellites in an Acipenser persicus genomic library. Of these 350 positively hybridizing clones were sequenced, and 81 clones were identified as having microsatellites with adequate flanking regions. We developed and tested 68 microsatellite primer pairs for Persian sturgeon. Out of 68 primer pairs developed, 11 pairs resulted in poor or no amplification, 13 were ambiguous, 6 were monomorphic, 20 were tetrasomic and 18 were octosomic in Persian sturgeon. While none of the markers showed disomic inheritance in Persian sturgeon and Russian sturgeon (A. gueldenstaedtii). Several of the markers appeared useful for studies stellate sturgeon (A. stellatus), ship sturgeon (A.nudiventris) and beluga (Huso huso). Nearly all the polymorphic pattern for ship, stellate and beluga displayed the simple banding patterns characteristic of disomic loci, while those for Russian sturgeon displayed banding patterns characteristic of tetraploid or higher polyploid levels. These markers may prove useful in a variety of future sturgeon population genetic studies in the Caspian Sea

The survey statistical and biological of sturgeon in the southern Caspian Sea (Mazandaran waters)

This study have been conducted entitle biological and statistical sturgeon in the southern Caspian Sea (Mazandaran waters)” from 2009 to 2013. Sampling was manthly. Overal, 1859 specimens of different species of sturgeon was caught including Acipenserpersicus (69%), A. stellatus (19%), Husohuso (6%), A. nudiventris (4%) and A. guldenstaedtii (2%). Totally, the meat and caviar of five species were found 53263.6 kg and 5633 kg respectively and caviar to meat ratio was 10.6%. The results show that ration of meat and caviar whole species reduced from 2009 to 2012 in which the meat and caviar of A. persicus was declined from 12146 to 4465 kg in meat and caviar from 1358 to 487 kg were extremely reduced respectively. The CPUE (catch per unit effort) of sturgeon has fluctuated from 2009 to 2012. Totally, the CPUE of A. persicus was decreased from 0.150 (2009) to 0.130 (2012) kg boat per day, A. stellatue from 0.009 (2009) to 0.021 (2012) kg boat/day, A. guldenstaedtii from 0.002 (2009) to 0.003 (2012) kg boat/day, A. nudiventris from 0.027 (2009) to 0.001 (2012) kg boat/day and H. huso from 0.123 (2009) to 0.018 (2012) kg boat /day. 1061 specimens of fish has been caviar including A. persicus with 69%, A. stellatus (18.1%), H. huso (5.5%), A. guldenstaedtii (2.7%). The frequency of caviar categorize was included 1 , 2, 3 and massive with 49.6%, 38%), 10.6% and 1.9% , respectively. The highest of meat and caviar belong to A. persicus with 31414 kg and 3515.7 kg, respectively were found and the lowest was 841kg and 105.9 kg pertain to A. guldenstaedtii. The results show that 65.9% of sturgeon was caught by legal catch (landing) and 34.1% by beach seine remained. 391 individuals was age determined that the minimum and maximum age was 9 and 41 year comprised to H.huso and A. stellatus, respectively. A. persicus and A. stellatus were majority caught compare to other species. A. persicus has the highest frequency in 14-15 year age groups with 50% and 57% in 2009 and 2011, respectively and 15-16 year age group with 41% and 56% in 2010 and 2012, respectively. The results show that mean of fork length, body weight, caviar weight of A. persicus was declined because the FL and weight average (±SD) obtained from 152.4±16.7cm and 25.8±9.2 kg in 2009 to 146.5± 18.7cm and 22.1±9.2kg in 2012, respectively. In contrast, the average (±SD) FL and weight of H. huso was increased from 218.8±41.1cm and 137.3±96.6kg in 2009 to 231.3±45.2cm in FL and 146.2±78.5kg body weight in 2012, respectively. Consequently, the results show that stocks of sturgeon in the Caspian Sea has a trend declined because of some species in IUCN categorize list was Endangered in 2006 but at this moment lie in Critically Endangered list of IUCN categorize were down which could be a serious alarm for the valuable sturgeon fish in the Caspian Sea. Therefore, recommendation that trade catch of sturgeon in the Caspian Sea must be forbidden and continue legal catch for spawner fish that needede to artificial propagation only

Isolation, characterization and application of micro-satellite markers in Persian Sturgeon, acipenser persicus borodine

The Persian sturgeon (Acipenser persicus) is one of the most valuable genetic resources, which is an endangered species. The development of a conservation program for this species requires knowledge of its genetic diversity obtained by using a reliable molecular marker system to ascertain its population genetic structure. Developing such markers in sturgeons that have polyploid ancestry is particularly challenging because many markers exhibit polysomic inheritance. For this purpose, several experiments were conducted to develop single locus deoxyribonucleic acid (DNA) microsatellite markers for the Persian sturgeon. An enriched library was prepared based on a modified biotin-capture method. Approximately, 1800 positive clones were screened. Out of these, 68 microsatellites primer pairs were designed and tested for use in the Persian sturgeon. While none of the loci amplified showed disomic inheritance in the Persian sturgeon, several of them appeared useful for studies of stellate sturgeon (Acipenser stellatus), ship sturgeon (Acipenser nudiventris), beluga (Huso huso) and Russian sturgeon (Acipenser gueldenstaedtii). Another approach namely cross species amplification was then used in the quest for disomically inherited microsatellite loci in the Persian sturgeon. For this purpose, 56 and 38 sets of microsatellite primer pairs developed in shovelnose (Scaphirhynchus platorynchus) and lake (Acipenser fulvescens) surgeons respectively were used in this study. Ninety four loci were successfully amplified and thirteen microsatellite loci that were polymorphic disomic loci were identified. This is the first report of disomic loci in the Persian sturgeon. For inheritance studies of these disomic loci, two F1 families of 23 and 28 larvae were produced in 1x1 crosses of the Persian sturgeons. Eleven microsatellite loci were used for genotyping parents and their offspring. This study verified the Mendelian inheritance and disomic segregation of all the investigated loci. The microsatellite markers developed and characterized here open a new perspective for generating fundamental data to devise sound conservation strategies for the polyploid Persian sturgeon and to provide assistance to wild stock enhancement programs for the species in the Caspian Sea. The findings obtained in the present study attest to the usefulness of the investigated microsatellites for parentage control in the Persian sturgeon. To evaluate the genetic diversity of the Persian sturgeons using 11 single locus DNA microsatellite markers, 167 sturgeon fish were randomly collected from Turkmenistan, Russia, Iran and the Sefid-Rud River region. The size number of the population of specific alleles ranged from 3 to 21 alleles. The mean values of observed heterozygosity were 0.56±0.20, 0.64±0.14, 0.67±0.16, and 0.64±0.11 in Turkmenistan, Russia, Sefid-Rud and Iran populations, respectively. It was also found that the observed heterozygosity is lower than the expected heterozygosity. This means that there is still inbreeding in the Persian sturgeon and a proper breeding program is essential to avoid increasing inbreeding in natural stocks. The Analysis of Molecular Variance (AMOVA) of microsatellites revealed that there are variations among populations and among individuals within populations Cluster analysis using admixture model showed evidence of similarity among all the investigated populations. The present analysis of investigated loci showed low or no genetic differentiation or low structuring across populations at all loci between populations

Studying Disabling Occupational Accidents in the Construction Industry During Two Years

Background & Objectives : Idnetifying causes of occupational accidents is a key issue to prevent these accidents. The present study aimed to identify and analyze debilitating accidents in the construction industry during a two-year period ( 2010 - 2011 years) . Methods: This was an analytical cross-sectional study. The study data included information about all debilitating accidents occurred within two years. Data collection was performed according to the accident report forms in construction sites. Data analysis was performed using SPSS software version 16. The level of significance was considered as P=0.05. Results: The mean age and job experience of injured people were 27.95±6.95 and 2.34±2.00 years, respectively. Most injuries to people were reported in hand (35.4%), legs (28.3%) and back (20.4%). Most of accident types were respectively related to slipping and falling (26.1%), throwing objects (21.7%), falls (18.6%), abrasion (16.8%) and clash (16.4%). Moreover, the main causes of accidents were related to lack of housekeeping (97.3%), lack of proper training (85.8%), lack of PPE (73.0%), unsafe acts (63.3%), unsafe conditions (32.3%) and equipment (22.6%). Conclusion: Analyzing causes of disabling accidents in the construction industry showed that important factors in these accidents included lack of housekeeping, failure to provide proper training, lack of suitable PPE, unsafe acts, unsafe conditions and equipment for the construction job

Application of microsatellite markers for genetic conservation and management of Persian sturgeon (Acipenser persicus, Borodin, 1897) in the Caspian Sea

A study was conducted to ascertain the genetic structure and the level of heterozygosity of Acipenser persicus in the Caspian Sea. A total of 167 fish were randomly collected from Turkmenistan, Russia and two regions of Iran. The number of alleles of eleven microsatellite markers ranged from 3 to 21 and the mean observed values of heterozygosity were 0.56 ± 0.20, 0.64 ± 0.14, 0.67 ± 0.16, and 0.64 ± 0.11. The observed heterozygosity was lower than the expected levels. The observed low genetic differentiation indicates that all populations are closely related. Hence, inbreeding is a potential problem, which should be taken into consideration in future breeding programs to avoid a further decline in genetic diversity

Evaluation of Diode laser (940 nm) irradiation effect on microleakage in class V composite restoration before and after adhesive application

Introduction: Nowadays, the main focus of dental studies is on adhesive dental materials; since clinical long-term success of bonded restorations depended more on marginal microleakage minimization. So, the aim of this study was Evaluation of Diode laser irradiation effect on microleakage in class V composite restoration before and after adhesive application. Materials and methods: In this in vitro-experimental study, standard class V cavity was prepared on lingual and buccal surfaces of 60 premolar teeth. For evaluation of microleakage, 60 teeth were divided randomly into four groups A, B, C, D (n=15): A) primer + adhesive (Clearfil TM SE Bond), B) primer + Diode laser + adhesive (940nm wave-length, 21J total energy, 0.7W power, 30s irradiation time) C) primer + adhesive + Diode laser D) primer + Diode laser + adhesive + Diode laser. Then, restoration was completed by Z250 composite. For data analyzing, we used SPSS 16 software. For statistical analysis, we used Non-parametric Kruskal-Wallis & Mann-Whitney tests at 0.05% significance level.  Results: According to non-parametric Kruskal-Wallis test, microleakage scores had not significant difference before and after laser irradiation on gingival margins (p=0.116). But, in occlusal margins the results were significant among the groups (p=0.015). Also according to non-parametric Mann-Whitney tests among the occlusal microleakage scores, group B and D (Diode laser irradiation after primer and Diode laser irradiation after primer and adhesive) showed significant results. Conclusion: This study findings showed that in 6th generation adhesives, Diode laser irradiation on self-etch primer before bonding have significant effect on reduction of occlusal marginal microleakage in class V cavities although there was no significant positive effect of Diode laser on gingival margins