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Annually, More than 6 millions of cyprinid fish including Silver Carp( Hypophthalmichthys molotrix ) , Big head (Hypophthalmichthys nobilis ) , Grass carp( Ctenopharyngodon idella ) , Common carp( Cyprinus carpio)and Pike perch ( Stizostedion lucioperca) are produced in Poldasht Shahid Kazemi Propagation Center and released to water resources of West Azarbaijan to restocking purposes. Also, a large number of these fish are transported to the water sources and fish farms of the other parts of the country. Septicemia caused by motile Aeromonas species is considered as the famous disease in freshwater fish. It considered to cause of heavy losses in cyprinid farms of Iran in spring and summer, in recent years. On the other hand, Spring Viremia of Carp is considered as a sever pathogen of cyprinid fish in different parts of the world and has listed as notifiable diseases by OIE. This study was carried out to isolate and identify motile Aeromonas bacteria and SVCV in propagated cyprinid and lucioperca fish of Poldasht Shahid Kazemi Propagation Center. For this purpose, 40 fish of each species (totally 600 specimens), respectively with average weights of 500± 0.3 mg in incubation hall and 10±1 g in earthen ponds were sampled to determine bacterial infection. Samples from kidney, spleen, liver, blood, skin and gills were taken and cultured on BA, TSA, BHIA and NA and biochemical and differential tests were done. The bacteriological results represented the lowest percent of contamination with A.hydrophila in kidney and liver (1.5 ± 0.2%) at incubation stage and the highest (75.9±0.12%) during transferring to water resources. Also, Bacterial agents including Aeromonas sobria, Escherichia coli, Micrococcus,Staphylococcus, Aeromonas sp., Proteus mirabilis, P.aeruginosa, P.fluorescens and Pseudomonas putida were isolated and identified from sampled tissues. To isolate SVC virus with prevalence rate of 2%, 150 samples from 5 mentioned species were taken from kidney, spleen, gill and brain tissues (fish with 10±1 g weight and one year old fish) before transferring to the water resources. All samples were tested using RT-PCR for virological tests. The results showed the probability of SVC virus in one year old big head. Confirmation of the virus in accordance with international guidelines and the OIE requires additional testing and cell culture, the coordination of these tests with the National Veterinary Organization(IVOC) was carried out, which confirmed the failure to verify the results of definitive diagnostic tests .Finally The virus was not approved by the IVOC. Iranian Fisheries Science Research Institute Published

Sampling for this study was carried out at the freshwater crayfish fishing season (May to December ) from the selected packs made from one of the harvesting centers at the first day ( harvesting and packing ) until the seventh day ( the export time ) using registered number to determine the handling effect ( live ) and changes in chemical and microbial indices in tail fillet stored at -18 ° C at days 1 and every 15 days considering 1 treatment and 3 replicates. The comparison of results mean (±SE) of the effects of handling on tested indices showed a significant reduction of protein percentage (dry weight) of tail filet at day 7 (13/85 ± 0/07) comparing with fishing day (16/1 ± 0/05) ( (p < 0.05). So that by increasing the handling and storage period, the amount of protein (dry weight) was reduced. Comparison of carbohydrate percent (dry weight) during handling showed a significant difference between the first day (2/8 ± 0/009) with the seventh day (0/9 ± 0/005 (p 0.05). Comparison of the mean (±SE) of total bacterial count (log CFU / g) and psychrophilic bacteria at different periods of tail fillet storage at - 18 °C showed significant differences at day1 ( 3.48 ± 0.00 and 1.0± 0.00) compared to day 180 ( 6.86± 0.85 and 6.75± 0.25) , respectively(p>0.05) .Comparison of Mean (±SE) of chemical indices for first day with day 180 were thiobarbituric acid ( mg malondialdehyde /kg ) (0.19/0 ± 0/07) and (1/45 ± 0/25), peroxide ( meq oxygen/ kg fat ) (0/81 ± 0/21) and (2/2 ± 0/3), total volatile basic nitrogen ( mg per 100 g fillet ) (13/21 ± 1/01) and (26/6 ± 1 / 40) and acidity (6/26 ± 0/08) and (6/55 ± 0/05), respectively which showed significant differences with each other (p < 0.05). Therefore, cited to the results of microbiological and chemical parameters, maximum shelf life longetivity of freshwater crayfish tail fillets packaged in the air is recommended as 5 months after freezing at – 18 °C. Iranian Fisheries Science Research Institute Published

Early recognition of diseases and pathogens transmitted from freshwater crayfish provides the possibility of early intervention and management in this regard and decreases the mortality and morbidity from infectious diseases. Hence, The awareness from presence and incidence rates of WSSD, YHD, IPN viruses are very important due to they are the most important zoonotic and infectious viruses in aquatic animals and crustaceans .Also , they cause serious reduction of the amount and quality of freshwater crayfish in the world. For this region, this study was carried out for the first time to detect the mentioned viruses in freshwater crayfish from North West of Iran. In this study, a total of 725 crayfish (145 specimens from each water resource) were sampled during 2013 -2014 from dam reserviors including : Aras ( West Azarbaijan, Caspian Sea Basin),Ardalan ( East Azarbaijan, Urmia lake basin) , Kazarj and karaghyeh (East Azarbaijan, Caspian Sea Basin),Shorabil(Ardabil, Caspian Sea Basin).All specimens were transferred to aquatic animals health and genetics laboratory of Iranian Artemia Research Center as live individuals under controlled condition. In order to virus isolation, the gill, Hepatopancreas, Hemolymph and pleopods were tested using PCR and RT-PCR methods. Suspicious samples were sent to the reference viral diseases diagnosis laboratory of Iranian veterinary organization.Screening results showed the probability of no contamination in freshwater crayfish from studied water resources. Therefore, it is recommended continuation of screening mentioned viruses by the authorities placed on the agenda. Iranian Fisheries Science Research Institute Published

Saltwater resources with Artemia (Brine shrimp) are the important ecosystems in Semi-arid Areas. That can play an important role in sustaining the economic and social system. Alternatively, will ensure that economic and social issues with of continuity and sustainability of these ecosystems resident. This study carried out "Effects of Artemia parthenogenetica culturing on socio-economic development of the eastern marginal lands, Qom Salt Lake" that was ordered by Qom province general directorate of fisheries during the 2012-2013. According to previous studies, despite the potential of human resources and Social conditions for the development of economic activities, factors such as the low groundwater and drying the salt lake , lack of fresh water in the region, environmental problems , successive droughts, prioritize and rationalize water use in agriculture, Artemia cyst harvest or Artemia culture has made virtually impossible with the current situation and has deprived the tools to make investments for the construction of earthen ponds and exploitation of native Artemia in the eastern margin of the Qom lake . Also, due to the occurrence of the Lake in the national park and privacy protection and Prohibited areas of environmental protection organization, it seems unlikely that this organization grant approval agreement required for any exploitation. Iranian Fisheries Science Research Institute Published

Early recognition of diseases and pathogens transmitted from freshwater crayfish provides the possibility of early intervention and management in this regard and decreases the mortality and morbidity from infectious diseases. Hence, The awareness from presence and incidence rates of WSSD, YHD, IPN viruses are very important due to they are the most important zoonotic and infectious viruses in aquatic animals and crustaceans. Also they cause serious reduction of the amount and quality of freshwater crayfish in the world. For this region, this study was carried out for the first time to detect the mentioned viruses in freshwater crayfish from North West of Iran. In this study, a total of 725 crayfish (145 specimens from each water resource) were sampled during 2013 -2014 from dam reserviors including : Aras ( West Azarbaijan, Caspian Sea Basin),Ardalan ( East Azarbaijan, Urmia lake basin), Kazarj and karaghyeh (East Azarbaijan, Caspian Sea Basin),Shorabil(Ardabil, Caspian Sea Basin).All specimens were transferred to aquatic animals health and genetics laboratory of Iranian Artemia Research Center as live individuals under controlled condition. In order to virus isolation, the gill, Hepatopancreas, Hemolymph and pleopods were tested using PCR and RT-PCR methods. Suspicious samples were sent to the reference viral diseases diagnosis laboratory of Iranian veterinary organization. Screening results showed the probability of no contamination in freshwater crayfish from studied water resources. Therefore, it is recommended continuation of screening mentioned viruses by the authorities placed on the agenda.

Aras dam reservoir situated in the northwest of Iran, west Azarbaijan province, is the only water resource of Astacus leptodactylus harvest in the country that more than 250tons of this species were exported to different countries all over the world, annually. On the other hand, one of the polices of Iranian Science Fisheries Institute is the release of this species into other water resources in the country and for this purpose, the study of risky diseases such as Crayfish pest ( Aphanomysis astasi ) and other zoonotic diseases are considered as the research priorities of aquaculture development of the country. This study was carried out to health screening of Astacus leptodactylus at Aras dam reservoir from winter 2013 to fall 2014. In this regard, A total of 394 harvested livefreshwater crayfish Astacus leptodactylus (255males, 139females) weretested. 9 epibionts and parasites peritrich protozoans were identified. From Metazoan parasites group, Branchiobdella kozarovi with incidence rate of (100%) in obtained samples was the only isolated organism from this group that identified up to species level. There was a heavy damage in gills of samples with Aeolosoma hemprichi (Annelid) in winter with90% prevalence. Furthermore, Other Epibiont fouling organisms such as Rotatoria; free living nematods and suctoria were observed in this survey. The fungi study of the lesions and melanized spots of mentioned samples revealed their infection to Penicillium expansum; Aspergillus flavus; Alternaria sp. ; Fusarium sp. and Saprolegnia sp. The results of bacterial study confirmed the presence of pathogen bacteria in Astacus leptodactylus. The most frequency percentage ( 15.16%) in hepatopancrease were related to Aeromonas hydrophila and the least one ( 1.37%) were due to Yersinia bacteria . Also, only Aeromonas hydrophila and Staphylococcus aureus were isolated and identified from heamolymph, respectively. The results revealed that the combination of Salmonella typhi, Escherichia coli and Staphylococcus sp. has caused the most infection rate while. Yersinia ruckeri and Salmonella typhi has caused the least infections in Astacus leptodactylus. According to the isolation of 6 bacteria species from hepatopancreas and 2 species from heamplymph , it can be concluded that hepatopancreas enjoyed the higher infection rate compared to haemolymph in the obtained samples. Iranian Fisheries Science Research Institute Published

This research was carried out to determined water reuse effects on growth indices of rainbow trout. For this reason 4 groups includes: control (with use of 100% fresh water), Test 1(rearing with use of 30% recycled water (with physical filtration) and 10% fresh water), Test 2(using of 10% recycled water (with physical filtration) and 30% fresh water), Test 3(using of 100% recycled water) was done. Fish stock of each groups were done with 62 fish in each square meter and average weight (15±1.5).The Growth index, SGR, CF, FCR, SR between different groups in each month was calculated and determined. In this research comparison the average of month growth increment between different groups indicated that significant decrease of growth in test groups with control group and also 1 and 2 groups with 3 group (p0.05). To comparison FCR, SR, MR has shown a significant difference between different groups to each other (p