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This study is attempted to compare the number of rings and circular scales that are formed during various ages on Liza saliens. Sampling was carried out monthly during 2012-2013 using beach seine fishing nets. 102 specimens of different sizes were collected and transferred to the laboratory in boxes containing ice. The age of fish was determined by the number of annual rings as well as, the number of rings in each annual area. The distance between rings in each annual area was also measured. The results showed that the maximum growth was demonstrated in the first and second years. In the first year of life, the scale radius was nearly 2823.3±366.5(µm) which decreased to 1223.9±236.0(µm). The result indicated that 48 percentage of growth scales occurred in the first year and this value is only 21.8% in the second year. The number of growth rings in the annual regions decreased with increase in age. The result demonstrated that the average number of rings was 95.5±17.6 in the first life year of the fish. If you take into account the number of growth ring through years in comparison with the number of days in a year, it is clear that one ring was nearly made in four days in the first life year and it gradually reached 7.5, 15.9, 21.9 and 31.7 in the second, fourth and sixth years of life, respectively. One ring was approximately made in each month at higher ages.

Background: Ferroportin (Fpn), a regulator of iron homeostasis is a conserved membrane protein that exports iron across the enterocytes, macrophages and hepatocytes into the blood circulation. Fpn has also critical influence on survival of microorganisms whose growth is dependent upon iron, thus preparation of Fpn is needed to study the role of iron in immunity and pathogenesis of micoorganisms. Methods: To prepare and characterize a recombinant ferroportin, total RNA was extracted from Indian zebrafish duodenum, and used to synthesize cDNA by RT-PCR. PCR product was first cloned in Topo TA vector and then subcloned into the GFP expression vector pEGFP-N1. The final resulted plasmid (pEGFP-ZFpn) was used for expression of Fpn-EGFP protein in Hek 293T cells. Results: The expression was confirmed by appearance of fluorescence in Hek 293 T cells. Recombinant Fpn was further characterized by submission of its predicted amino acid sequences to the TMHMM V2.0 prediction server (hidden Markov model), NetOGlyc 3.1 and NetNGlyc 3.1 servers. The obtained Fpn from indian zebrafish also contained eight transmembrane domains with N- and C-termini inside the cytoplasm and harboured 78 O-glycosylated amino acids. Conclusion: The recombinant Fpn from Indian zebra fish was successfully expressed in Hek 293 cell line. Although the discrepancy in two amino acids was observed in our produced Fpn and resulted in an additional O-glycosylation site, but had no effect on the topology of the protein compared to other Fpn described by other researchers. Therefore this construct can be used in future iron studies.

Khark and Kharko Islands are located at far northern point of fringing coral reefs in the Iranian coast of the Persian Gulf. These coralline are the habitats of the wildlife refuge with total area of 2400ha and located in the territory of Bushehr province. The present study was carried out from July 2006 to June 2007 over 12 stations. Sampling was conducted obliquely from bottom using Bongo-net plankton sampler with 500µ of mesh size. In total, 1808 specimens, both in pre and post flexion stages were collected and examined. They were belonging to 45 families from different ecological groups (21 coralline and 24 non coralline fish larvae families ). 96% of examined fish larvae were in preflexion stage. Some families are new ones from the area . Among identified families, Clupeidae, Blenniidae, Sillaginidae, Atherinidae and Tripterygiidae were dominant families in studied area and the peaks were estimated in spring. The mean abundance of total fish larvae was 18.71 per 10m² of sea surface. The most abundant families were Clupeidae, Sillaginidae, Blenniidae, Atherinidae and Tripterygiidae in which comprised 65% of fish larvae. Abundance in spring showed significant difference with other seasons. The distribution pattern of fish larvae changed seasonally in both groups, increasing in east coasts of Khark Island and in three coastal stations during summer and autumn and in west coast of Khark in spring. The distribution of fish larvae seemed to be correlated to sea currents. Article includes abstract in Farsi on last page.

The annual reproductive cycle of peal oyster Pinctada fucata was characteised by documenting gonadal development and changes in serum levels of estradiol-17b (E2), testosterone (T) and progesterone (P) in the wild bivalve caught in natural beds in the Persian Gulf throughout the year. Bivalve populations employed in this study spawn in June-July and November-December. The pearl oysters had group synchronous ovarian development with exogenous vitellogenesis during spring and summer for first spawning and during August-September for the second spawning. Serum E2 levels in the females increased rapidly from low values in May to peak in June and also in October coinciding with the time of spawning. Serum T levels in male and female exhibited a bimodal pattern. However in the male it increased during the early spermatogenesis. P was detected in both females and males. Its concentrations start to increase during the early gametogenesis and reaching to peak during the spawning season. The obtained results indicated that vitellogenesis and spermatogenesis in pearl oyster are not completed by the mi-summer and early winter.

The population dynamic parameters of Vimba vimba persa (Pallas, 1811) were investigated from 994 specimens collected in the Iranian waters of the Caspian Sea from October 2008 to September 2009. Fork length ranged from 9.5 to 23.4 cm. Von Bertalanffy growth parameters from size-at-age data are: L∞ = 26.1 cm, K = 0.28 yr-1, to = -0.65. The length-weight relationship coefficient b for males (b = 3.128) was higher than that for females (b = 2.971). The oldest fish was 5 years old. Sex ratio was 1:1.35 (n = 935) with females predominating. Using the catch curve method, the instantaneous coefficient of total mortality Z was estimated as 1.07 yr-1. The instantaneous coefficient of natural and fishing mortality M and F were 0.58 and 0.49 yr-1, respectively. The current exploitation ratio E = 0.46 indicated that the population seems to be highly exploited, and probably not at a sustainable level.

The histopathological effects of Linear Alkylbenzene Sulfonate on the gill, liver and kidney tissues of the Caspian kutum, Rutilus frisii kutum were studied. The fish were exposed to three sublethal concentrations of anionic detergent, Linear Alkylbenzene Sulfonate (LAS) for short term intervals (192 h). Gill, liver and kidney samples were collected after 192 h of exposure to LAS and lesions were analyzed by light microscopy. The histological changes to gills were edema, fusion of lamellae and lamellar aneurism. Some alterations like reduction of the interstitial haematopoietic tissue, tubular shrinkage, degeneration in the epithelial cells of renal tubule and necrosis were observed in the kidney. In the liver tissue, hepatocyte degeneration, congestion and dilation of sinusoid and vacuolar degeneration were seen. It seems that sublethal concentration of LAS may affect severe changes to gill, kidney and liver of R. frisii kutum specimens that leads to malfunction of these organs which cause damage to health of the fish. Article includes abstract in Farsi on last page.