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Rainbow trout, Oncorhynchus mykiss is the most important cold water farmed fish as a nonindigenous species in Iran. Eyed eggs have been imported from different countries to Iran. In this study, genetic diversity of 50 fish (male and female) from Iranian generation and 24 fish from French generation were evaluated. Six microsatellite markers including OMM1019 ،OMM1036 ،OMM1307 ، OmyFGT5TU ،Omy77DU and Omy207UoG were applied. Average number of observed alleles in the Iranian and the French stocks were 6.68 and 6.83, respectively. Average number of effective alleles in the Iranian and French stocks were 3.13 and 3.45, respectively. Mean expected and observed heterozygosis was 0.68, 0.53 and 0.71, 0.61 in Iranian and French stocks, respectively. The results showed significant deviation from Hardy-Weinberg equilibrium at the most of loci × stock. Fixation index Fst calculated based on allelic frequency between two stocks was 0.058 with significant difference between 2 stocks. The results of this study showed insignificant genetic differentiation based on six microsatellite loci.

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In this study the rainbow trout (Oncorhynchus mykiss) myostatin gene (MSTN) for detecting gene derived SNPs and performing genetic association study between MSTN polymorphisms and growth traits were analyzed. Twenty broodstocks of rainbow trout in Genetic and Breeding for coldwater Fishes center in Yasouj for generating full sibling were selected and tagged and then juveniles were raised at the ponds until 5 months post-hatching. DNA extract based on standard method and these individuals selected randomly for molecular analysis. Two single nucleotide polymorphisms (SNPs: g.660T>C and g.1904C>A) in intron 1 and 2 regions of the MSTN gene in rainbow trout by were identified DNA sequencing and polymerase chain reaction single-stranded conformational polymorphism (PCR-SSCP) methods. The assessment results demonstrated that 6 haplotypes were revealed in this center. Moreover, association analysis indicated that the genotypes of SNP g.1904C>A are associated with the length and body weight at 90 and 150 days of age (P< 0.05), whereas no significant association was found between the SNP g.660T>C and growth traits. Our results provided evidence that SNPs in MSTN gene may be associated with length and body weight at fingerling age and MSTN gene may be used as potential candidate gene for marker-assisted selection (MAS) in rainbow trout breeding program

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During the growth of population in the world, Recirculating Aquaculture Systems (RAS) are developing due to more production and less water consumption and many scientists have studied on water quality and solid removal at these systems. In this paper to study on settling pattern of solid particles on a bed of aquaculture cylindrical tanks, a tank in diameter of 2.14 m and height of 0.59 m and inlet flow using three nozzles in 8 mm diameter has implemented. Quality and quantity studies of settling patterns of solid particles in six injection location (by changing the injection location of radial alignment for three options and on the pyramid of tank for others) show that injection location by the middle location of radial length and of third station (there are 6 stations on the pyramid of the tank and each station has located at 60 degrees from the last station) created more uniform sedimentation on the bed. Also, laboratory observations show that the low density materials such as fish feed, which has a high rate of immersion are more disposed to exit due to spiral flow of cylindrical tanks.

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The present research project has been implemented with the aim of introducing aquatic research axes based on the pillars of food security. For this purpose, the stakeholders, strengths and weaknesses, threats and opportunities of the sub-sector of fisheries and aquatics were investigated and the basic research axes were determined based on the elements of food availability, access to food, food consumption and health, and the stability and sustainability of food. Also, in addition to determining the research axes, the research priority of different groups and species of aquatic animals was determined based on the scoring index (0-10). The results showed that the beneficiaries of the fisheries sector have a wide range and the main ones who will directly benefit from the research results are aquaculture farmers, fishermen, processors and exporters of aquatic products. From the point of view of strengths, weaknesses and opportunities and threats, the existence of valuable genetic resources, fisheries knowledge and the country's policies for the development of fisheries and aquatics are among the strengths, and natural factors such as pollution of water resources, reduction of marine resources and climate change are among the most important threats. are counted From the point of view of the main axes of research in the pillar of food availability, fishing, stock assessment, aquaculture, health and aquatic diseases, in the pillar of access to food, supply markets, economic and social issues and the final price of the product, in the pillar of food consumption, quality and consumption culture, in the pillar of food sustainability, sustainable exploitation of aquatic life, reduction of waste, and increase in productivity were identified as priorities. In terms of species priority based on fertility, cold-water fish breeding, production management in shrimp, cold-water and warm-water fish, product health and transformation industries were given the highest points. In Caspian Sea aquatics, the most research points were given to health, nutritional value, storage, maintenance and market, and important Persian Gulf and Oman Sea aquatics received the most points for health and exploitation management.