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Mirheydari S.M.,Islamic Azad University at Tehran | Soltani M.,University of Tehran | Kamali A.,Islamic Azad University at Tehran | Asadpour-Ousalou Y.A.,Iranian Artemia Research Center | And 2 more authors.
Iranian Journal of Fisheries Sciences | Year: 2014

This study was carried out with the aim of examining the seasonal reproductive cycle of the female crayfish Astacus leptodactylus from Aras Dam Lake, Western-Azerbaijan, Iran. Gonadosomatic index (GSI), and oocyte size were measured in females sampled seasonally in June, August, November(2011), January(2012). Development of the oocytes was categorized according to the diameter and the presence/absence of yolk granules. The ovary development was accompanied by increasing levels gonadosomatic index and egg diameter. Ovarian development histologicaly related to the seasonal GSI . This index was low in June (0.61±0.05) when oocytes started developing and reached the highest value in November (13.53±0.25), when vitellogenic oocytes were abundant in the mature ovary. Our results highlight the relationship between the ovary development and the GSI and egg diameter in the crayfish A.leptodactylus during the reproductive cycle and held important implications for the management of aquatic species. Thus, investigation of female A. leptodactylus reproduction is highly significant for fisheries managers as well as environmentalists concerned with perpetuating crayfish stocks. Source

Asem A.,National Park Society NGO | Rastegar-Pouyani N.,Razi University | de Rios P.L.,Catholic University of Temuco | Manaffar R.M.,Urmia University | Mohebbi F.,Iranian Artemia Research Center
World Academy of Science, Engineering and Technology | Year: 2010

Nowadays, biometrical characterizations of Artemia cysts are used as one of the most important factors in the study of Artemia populations and intraspecific particularity; meanwhile these characters can be used as economical indices. For example, typically high hatching efficiency is possible due to the small diameter of cysts (high number per gram); therefore small diameter of cysts show someway high quality of cysts. This study was performed during a ten year period, including two different ecological conditions: rainy and drought. It is important from two different aspects because it covers alteration of A. urmiana during ten years also its variation in the best and worst environmental situations in which salinity increased from 173.8 ppt in 1994 to 280.8 ppt in 2003/4. In this study the biometrical raw data of Artemia urmiana cysts at seven stations from the Urmia Lake in 1994 and their seven identical locations at 26 studied stations in 2003/4 were reanalyzed again and compared together. Biometrical comparison of untreated and decapsulated cysts in each of the seven similar stations showed a highly significant variation between 1994 and 2003/4. Based on this study, in whole stations the untreated and decapsulated cysts from 1994 were larger than cysts of 2003/4 without any exception. But there was no logical relationship between salinity and chorion thickness in the Urmia Lake. With regard to PCA analyses the stations of two different studied years certainly have been separated with factor 1 from each other. In conclusion, the interaction between genetic and environmental factors can determine and explain variation in the range of cysts diameter in Artemia. Source

Asadpour-Ousalou Y.,Iranian Artemia Research Center | Mirheydari S.M.,Islamic Azad University at Tehran
World Applied Sciences Journal | Year: 2014

Super Selco is an Artemia enrichment compound in aquaculture. Artemia has enjoyed great applications as a live food. However, it has low values of EPA and lack of DHA. Commercial emulsions such as selco have been made to enrich Artemia worldwide, but encountered to import limitations. In this study, enriched emulsion of Artemia was made with reverse engineering using waste materials and by products of aquatic animals harvest (Scomberidae, squids wastes and of olive oil extraction factories. Suspensions were tested and enriched Nauplii then were analyzed by G.C. The enrichment percentage of Nauplii in evidence and homemade samples were achieved as 27.47 and 22.14 %, respectively. Enriched live Artemia nauplii were biometrically measured containing 500 early feeding Oncorhynchus mykiss larvae which was consisted of 3 treatments and a control diet. The results revealed that treatments 1 and 2 showed a significant difference with treatment 3 and 4 on survival rate, growth coefficient and mortality rate Final results approved that there is the talent of selco enrichment oils production similar to foreign samples by interior potential. © IDOSI Publications, 2014. Source

Ahmadi R.,Iranian Artemia Research Center | Mohebbi F.,West Azerbaijan water authority organization | Hagigi P.,West Azerbaijan Environment Protection Organization | Esmailly L.,West Azerbaijan Environment Protection Organization | Salmanzadeh R.,West Azerbaijan Environment Protection Organization
International Journal of Environmental Research | Year: 2011

This research summarizes the data on benthic macro invertebrates collected from 25 points in the urmia Lake wetlands during November 2008 to February 2009. The purpose of the study was to assess the effects of elevated salinity and nutrient (nitrogen and phosphorus) levels on macro invertebrate abundance and composition. A total of 32 taxa were collected, and the common taxa, including Chironomidae (midges), Corixidae (water boatmen), Erythemis (damselflies), Ephemerella (mayflies), Hyalella (amphipods), and snails. Samples at ponds with salinities greater than 10 ppt showed a shift in community composition to salt-tolerant taxa and a reduction in total diversity. The corixid Trichocorixa verticalis, the brine shrimp Artemia partenogenetica, and the dipteran Ephydra are salt-tolerant species that only occur at high salinity levels. Ponds relatively high in nutrients had fewer total taxa, reduced abundance and diversity of aquatic beetles, lower diversity index values, and a greater dominance by chironomids than ponds low in nutrients. It is suggested to allocate about 10 ×10 6 cubic meters freshwater of the represented rivers to these wetlands to improve their trophic condition and transfer their hypereutrophic waters into the Urmia Lake for more production of the macro invertebrates both in the wetlands and on the lake. Source

Mohebbi F.,Iranian Artemia Research Center | Mohsenpour Azari A.,Iranian Artemia Research Center | Heidari M.,Agricultural and Natural Resources Research Center of Iran | Asem A.,Afagh High Education Center
International Journal of Environmental Research | Year: 2012

Occurances of cyanobacterial bloom typically appear in eutrophic lakes which either have been affected by anthropogenic nutrient loading or are naturally rich in nutrients. Microcystis blooms have been reported all over the world in freshwater ecosystems mainly due to increased population which results in increased the waste water production. The aim of this study was to recognize the basic reasons of Microcystis aeruginosa bloom in Aras reservoir. Water temperature, pH, DO, EC, TN, N-No 2, N-No 3, P-Po 4, chl a and the number of Microcystis colonies were determined. The effects of these parameters on the microcystis increased growth was examined. Though we could not strictly relate a few other factors to this phenomenon, higher water temperature, pH and DO in the sampling site i.e. 27° C, 9.16 and 17.2 mg/L respectively, surely favored the M.aeruginosa bloom. In brief, preventing or reducing the nutrients flow into the reservoir should be considered as a priority in order to reduce Microcystis scum forming colonies. Source

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