Stock assessment of Huso huso (Linnaeus, 1754) in the south Caspian Sea

We evaluated the stocks of Huso huso in the south Caspian Sea along Iranian coasts using data on different population parameters such as length, age, weight, catch and catch per unit effort changes. The study covered data from 1971 to 2003. The stocks and catch rate of H. huso shows a decrease during the last three decades. The recorded catch for the years 1971-1972 was 74 tons with 5.55kg catch per unit effort which was decreased to 38 tons with 0.26 kg per unit effort in 2003 in gillnet fishery and the same trend was observed in beach seine fishing. The data shows that during 1990 to 2003, the average length of the fish has increased from 192.8 to 216.2 centimeters and the average weight has improved from 73 kg to 116.3 kg. Age frequency comparison between the catch of the years 1990 and 2003 showed that with time, older age classes replaced the younger ones, hence the increase in the length and weight of the fish. Due to the decrease in the younger fish and the increase in illegal fishing, it is anticipated that the fish stocks will suffer a decrease in future

Evaluation of Russian sturgeon stocks (Acipenser gueldenstaedtii) in the southern Caspian Sea, Iran

The changes of Russian sturgeon stocks in the southern Caspian Sea was studied by measuring and considering different population parameters such as fish length, weight and age and also fluctuation of catch and catch per unit effort. Amount of catch and biomass showed an descending trend during last 3 decades. In 1971-72 catch and CPUE of Russian sturgeon had been 837 tons and 602 kg/boat/day and was decreased up to 57 tons and 0.34 kg/boat/day in 1999. The abundance of young fishes was decrease during last decade and older fishes have been dominated at present. Because of a sharp decrease of sea ranching of Russian sturgeon fingerlings and consequently decrease of young fish abundance, therefore it is predicted that amount of catch will be considerably declined in the future

By-catch of sturgeon juveniles in beach seine fishing method in Mazandaran Province, northeast Iran

In an attempt to recognize the harmful fishing times and locations for sturgeons, we used catch statistic to evaluate by-catch of sturgeon juveniles during beach seine fishing over the years 2001-2002 in Mazandaran Province. We found that over the fishing period, 23760 hauls were conducted during which 103000 sturgeons were caught. The highest by-catch occurred in October (37% of the catch) and the lowest occurred in January (5% of the catch). The maximum sturgeon catch per haul was 14.2 in autumn decreasing through the year with 1.26 sturgeon fish caught in each haul in spring. The species composition of the by-catch sturgeon juveniles was determined to be Persian sturgeon (54%), Stellatus sturgeon (37%), Beluga (6%), Russian sturgeon (2%) and Spiny sturgeon (1%)

Determination of sex and maturity in Acipenser stellatus by using ultrasonography

Knowledge of both sex and maturity stage without killing fish is important from many aspects. The establishment of accurate sex and maturity determination without external sexual dimorphism or when external characters are not developed has usually involved the use of either hormone radioimmunoassay or biopsy techniques. These methods are time and labor consuming as well as harmful to fish. Therefore, it would be economically important for caviar producing countries to develop accurate, effective and non-invasive method for determination of sex and maturity in sturgeons. Ultrasonography examination was performed to determine sex and differences between matured and immatured Acipenser stellatus. The 249 captured stellate sturgeons larger than 95 cm in length were examined with a linear transducer. Sex determination was carried out based on the differences in echogenicity and morphology of the ovaries and testes. Results of ultrasonography were confirmed at necropsy: 199 fish were female (63 matured and 136 immatured) and 50 were male (29 matured and 21 immatured). Ultrasonographic examination resulted in sex determination with 97.2% accuracy. Gonads of immature males may be difficult to discern. The speed of examination was around 30 seconds or less per fish depending on the stage of maturation of fish

Study on starred sturgeon (Acipenser stellatus) stocks in the suthern coast of the Caspian Sea

Starred sturgeon is the most commercial sturgeon species in the Iranian coast of the Caspian Sea. The condition and the development of its stocks need scientific investigation. During the past few years Mazandaran Fisheries Research Center has tried to study the condition of these stocks to the possible extent. In this paper we have tried to describe and analyze the taxonomy, biology, ecology and different parameters such as catch data, catch per effort, length, age, weight, sexual stages and the caviar in regard to starred sturgeon. The obtained results revealed that starred sturgeon stocks are diminishing

Digestive system anatomy of the Acipenser persicus: New features

Sturgeon is one of the most important species of the Caspian Sea aquatics. Unfortunately, this species faces the threat of extinction today. This makes specific studies on any type of sturgeons more important than before. Studies like histological studies, radiology, and sonography, all require a complete understanding of the anatomy of this fish. Since pilot studies showed some misconceptions in description of the sturgeon digestive system, this study was conducted to evaluate more precise anatomical structure of the digestive system of Acipenser persicus as the most important sturgeon species of Iran. A total of 40 adult Acipenser persicus were used in this experiment. They were autopsied primary to the study. All parts of the digestive system from buccal cavity toward rectum and anal orifice were evaluated. The anatomical structure and relations of the different parts of the digestive system including oral cavity, pharynx, esophagus, glandular stomach, muscular stomach, pyloric process, small intestine, spiral intestine, rectum, liver and pancreas were described. The digestive tube is relatively short. The stomach has two parts. The first part, or the proventricle, is U-shaped. The second part or gizzard has thick muscles and is almost surrounded with liver lobes. Pyloric caecum is located on the left side bottom of the gizzard as a sponge like structure. The intestines are made of 3 parts: the small intestine, the spiral colon, and the rectum. The small intestine has two flexures that separate it to three parts named the descending, ascending, and the end part, respectively. The spiral colon is the longest part of the digestive tube. This part has mucosal spiral septum on the inner surface. The rectum is short and located in the middle of the abdominal cavity. However, in the present study the opening was shown to be located in the muscular stomach and the intestine junction, just close to the gall bladder duct opening

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

Phylogenetic analysis of prevalent tuberculosis and non-Tuberculosis Mycobacteria in Isfahan, Iran, based on a 360 bp sequence of the rpoB gene

Background: Taxonomic and phylogenetic studies of Mycobacterium species have been based around the 16sRNA gene for many years. However, due to the high strain similarity between species in the Mycobacterium genus (94.3 - 100), defining a valid phylogenetic tree is difficult; consequently, its use in estimating the boundaries between species is limited. The sequence of the rpoB gene makes it an appropriate gene for phylogenetic analysis, especially in bacteria with limited variation. Objectives: In the present study, a 360bp sequence of rpoB was used for precise classification of Mycobacterium strains isolated in Isfahan, Iran. Materials and Methods: From February to October 2013, 57 clinical and environmental isolates were collected, subcultured, and identified by phenotypic methods. After DNA extraction, a 360bp fragment was PCR-amplified and sequenced. The phylogenetic tree was constructed based on consensus sequence data, using MEGA5 software. Results: Slow and fast-growing groups of the Mycobacterium strains were clearly differentiated based on the constructed tree of 56 common Mycobacterium isolates. Each species with a unique title in the tree was identified; in total, 13 nods with a bootstrap value of over 50 were supported. Among the slow-growing group was Mycobacterium kansasii, with M. tuberculosis in a cluster with a bootstrap value of 98 and M. gordonae in another cluster with a bootstrap value of 90. In the fast-growing group, one cluster with a bootstrap value of 89 was defined, including all fast-growing members present in this study. Conclusions: The results suggest that only the application of the rpoB gene sequence is sufficient for taxonomic categorization and definition of a new Mycobacterium species, due to its high resolution power and proper variation in its sequence (85 - 100); the resulting tree has high validity. � 2016, Ahvaz Jundishapur University of Medical Sciences

Confidence College – an online education tool for neurology patients

COVID-19 and its aftermath highlight the importance of patient self-care and involvement in monitoring and improving their health. Resources to guide this are essential. Our objective was to create a web-based patient education tool, to facilitate patient education and empowerment for people with epilepsy, multiple sclerosis and Parkinson’s disease, available without cost to patients, carers and clinicians. This project was conducted within community and secondary neurology services. Patients and their carers were involved in designing, reviewing and revising the tool, as equal partners with clinicians and digital engineers. A web-based design template was developed with graphics and links to enable patients to create personalised plans. Participants are patients, carers, clinicians (neurology consultants and specialist nurses), neurological charities, the London Neuroscience Clinical Network, NHS England and Shift.ms (a service design team with experience in creating digital services for individuals living with neurological conditions). Shift.ms conducted in-depth interviews. Clinicians used evidence from personal and PubMed databases. Shift.ms analysed and co-ordinated the responses, and designed the pilot tool. Confidence College provides a delivery model for patient education relating to multiple sclerosis, epilepsy and Parkinson’s disease. It requires follow-up evaluation regarding uptake. This web-based accessible patient empowerment tool has no limit on recurrent use, low maintenance costs and no additional costs in up-scaling the number of users. It is ideally suited for use during and after the COVID-19 pandemic

Determination of catchability bony-fish and optimized exploitation in the Caspian Sea

To accomplish the stock assessment that pre-planned for bony-fish resources investigation started by considering two pivotal act. First gathering biometric data and second using catch statistics information for stock analyses. Implementing the research programmes five itinerant groups in Anzali, Keyashahr, Noshahar, Babolsar, Torkaman have been organized during fishing season. The biometric data were supplied in computer that distincted by each fish species and subdivided into age groups. In analyses the samples, Bertalanffy formula used for calculating average length and age, also for growth coefficient. Total mortality rate calculated by using Pauly formula, and the biomass status estimated through Cohort analysis. The catch by beach seiner cooperatives recorded 8630 metric tons, but estimation including. Poacher catch raised the harvest to 15.6 thousand tons. The total catch of Kutum reduced by 1400 tons compared with previous year, but the estimation revealed the biomass of Kutum 18.5 thousand tones, the stock stowed reduction in quantity relative to past years. Harvest exceeding the limit, fishing pressure. And employing higher fishing effort, combining releasing the Kutum seedling with shorter average length in recent years, leaded the shrinkage of biomass of Kutum resources. The Golden Grey mullet catch has been estimated 3437 metric tons, the figure showed 1500 tons increment, in comparison with previous year, nearly 24% of catch was shorter than Lm50% of this species. In Guilan province higher number of sub - size golden mullet captured, this development occured less in Mazandaran and Golestan province. Higher rate of exploitation, reduction of catch in recent years, dominating small size fish in catch composition indicated the population undergoing stress in ecosystem. Thin - lipped grey mullet only comprised 9.2% of the mullet catch - Length - structure of this fish species population formed mainly by young small size fish, the biomass of latter estimated 1100 metric tons. Catch further than maximum sustainable yield, by higher exploitation rate, and gradual diminishing of harvest, represented the resources of this fish species suffering both by high fishing pressure and un - sustainable effort, which ultimately declined the fishery of this fish species. Carp catch and its resources in Anzali region become very low, it is necessary to enhance the stock by Sea-ranching programmes. The carp resources in Gorgan region enjoy better status, but catch practices do not compatible with rule and regulation in Gorgan and Gomeyshan area. The standing stock of Gorgan carp estimated nearly 6000 tons. The information concerning carp resources indicate the stock experiencing pressure and likely the catch will diminish in future. The total catal catch of carp calculated 1900 tons. In recent years the Caspian roach resources are increasing but the bulk of harvest fished illegally and by gill - nets. The total catch of the roach during 1998-1999 estimated 1700 tons. Considering the semi - artificial propagation of roach in Golestan province, if has been concluded the multiplication of this fish species also should be planned by fisheries authorities for Anzali region. It is also advisable catching of this fish species to be regulated soon and selective catch are proposed. The catch of pike - perch during the year of 1997 - 98 jumped to 95 tons, but 90% of catch formed by young fish or sub – standard length size. Almost, all the increment of catch attributed to the releasing of millions of seedlings in the Sea which the plan has been implemented by Iranian Fisheries. Increasing the numbers of released seedlings, with higher average weight Identification of most suitable site for unloading the fries could ensure better survival rate and contribute the enhancement of resources and produce good catch for this desirable fish species. The total catch of Bream hit 18 tons, but most of the catch comprised by young fish with sub - standard size. The present formation of fisheries population of bream are the result of seedling releasing! In the Sea by Iranian Fisheries, since the catch of bream are negligible despite releasing programmes of seedling in a decade which 14million individuals until now, one could conclude the programmes do not contributed effectively to stock rehabilitation. The Caspian Barbus (Barbus brachycephalus) are at the threshold 01 vanishing, at present a few numbers are caught, therefore B.capito appeared in catch composition. The catch of latter species in recent two years are increasing. Total catch during the year of 1998 - 99 estimated 34.5 tons, biomass calculated 93 tons. Caspian vimba are small size fish which beach seiner (mesh size in bosom 30 millimeters) could not capture them ideally, bulk of the catch caught in illegal manner by gill nets. The total catch estimated 154 tons which the present fishing procedures surpassed total allowable catch (136 tons). In recent years the catch of this fish species are increasing. "Shemaya' similar in size with Vimba are caught less by beach seiner, illegal catch are considerable, the total catch in 1998 - 99 estimated 86 tons. The level of harvesting of this fish species are increasing in recent years and its population size become significant relative to last years. The main part of catch concerning Aspius fish species occured in Guilan coastal area, high fishing pressure reduced the population size, including low discharge of water in rivers during spawning period, impact negatively to reproduction. Catch statistic in 1989 showed 128 tons of this fish species are caught but in 1998 - 99 it has been reduced to 6.8 tons. It has been suggested artificial spawning could prevent its fate as endangering species. Caspian salmon catch estimated 78 tons during 1998 - 99, salmon population in Caspian Sea are supported by releasing reared smolts, which in recent years nearly 500 thousands fingerlings released in suitable rivers. After banning the gill nets application in Southern Caspian Sea, the catch of salmon in beach seining are increasing. It is necessary the released smolts in rivers being protected for its safe approach to Caspian Sea. The total catch of herring fish species in 1998 - 99 were nearly 700 tons. The bulk of the catch occur In Guilan fishing area, elimination of gill - nets usage in Southern Caspian Sea contributed the increment of herrings catch in beach seining. The herring resources in Caspian Sea reduced relative to past decades. The catch during 1913 – 1916 ranged between 130 - 160 thousand tons, in Caspian Sea