Gonadal changes and serum steroid levels during the annual reproductive cycle of the pearl oyster Pinctada fucata Gould

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

Histopathological changes of gill, liver and kidney in Caspian kutum exposed to Linear Alkylbenzene Sulfonate

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

Estimation of growth parameters and mortality rate of common carp (Cyprinus carpio, Linnaeus 1758) population in the southern Caspian Sea

Common carp (Cyprinus carpio) represents one of the most economically important fish species in the Caspian Sea. In this study, growth and mortality parameters among population of common carp was investigated. Sampling was carried out weekly, using beach seine in the south of the Caspian Sea from October 2006 to September 2007. As a contribution to elaborating management programs for common carp, the age and growth of this species was calculated via scale, growth parameters and mortality rate by length frequency data obtained from commercial fishing and research beach seines. Ten age groups were recorded from 1+ to 10+ years old, being dominated by 4 and 5 year-old fish. The growth parameters based on scale reading data by length at age analysis were FL∞= 71.52cm and K = 0.16 per year for total population, FL∞= 70.54cm and K = 0.15 per year for males, and FL∞= 72.00 cm and K = 0.16 per year for females, whereas by length frequency analysis, these values were estimated as FL∞ equals 72.0, 69.3 and 73.0cm and K equals 0.18, 0.15 and 0.18 per year for total population, males and females, respectively. The total, natural and fishing mortality rates were 0.71, 0.29 and 0.42 per year, respectively

Reproduction characteristics of the Vimba vimba persa (Pallas, 1811), in coastal waters of the Caspian Sea

Some reproduction characteristics of the Caspian Vimba, Vimba vimba persa, were studied from Oct. 2008 to Sep. 2009 in coastal waters of the Caspian Sea (Mazandaran province). 994 specimens were monthly collected from 6 fish landing sites of Ramsar, Tonekabon, Chalus, Mahmood Abad, Sari and Behshahr. The fecundity was measured using 92 specimens. This species was found to have more abundance in spring (especially April and May). The samples composed of 397(42.6%) male, 537(57.4%) female; the sex ratio was M:F = 1:1.35. The advanced stages of maturity (4th & 5th) were found in April and May. The highest Gonadosomatic Index in females was in May and the lowest one was in July. The average of absolute and relative fecundities was 17198±7710 and 171.85±48.8, respectively

Extraction and identification sterols in brown alga, Padina boergesenii in Chabahar Coasts

Padina boergesenii is one of the most abundant brown algae distributed in the north of Persian Gulf and Oman Sea. In this study after sampling and preparation of Padina boergesenii by Chroform-Etanol (3-1) solvent and by Methanol has been extract. Separation and purification of the compounds was carried out using thin layer, general and inverse column chromatography, Cephadex and high-performance liquid chromatography (HPLC). Structural elucidation of the constituents was based on the data obtained from H-NMR, 13C-NMR, HSQC, HMBC, DEPT and Cephadex LH-20. The steroids compounds separated from above alga were identified as 22-dehydrocholesterol (1), cholesterol (2), fucosterol (3), β-sitosterol (4), stigmasterol (5), ostreasterol (6) and two epimer of hyroxyestrol (7), based on their spectral data and from comparison with those previously reported in the literature

Histopathological effects and toxicity of atrazine herbicide in Caspian kutum, Rutilus frisii kutum, fry

This study aimed to investigate the toxic effects of atrazine herbicide on the fry of Caspian kutum (Rutilus frisii kutum, Kamensky, 1901). First the 96-h LC50 of the fry were exposed to atrazine at the concentration of 24.95 ppm was determined. Then the toxicity of this herbicide on Caspian kutum fry exposed to the concentration of 12.47ppm (1/2 LC50), for four days was measured and compared with a control group. Comparison of the length, weight and condition factor showed no significant differences between atrazine exposed and control group. The concentration of Na+, K+, Ca2+, Mg2+ and Cl- in the whole body of fry in control and atrazine exposure groups were as the following order: Ca2+>K+>Na+>Cl->Mg2+ and Ca2+>Na+>K+>Mg2+>Cl-, respectively. Results showed that the concentration of all these ions were higher in atrazine exposure group than control group, except for Cl-, and the only significant differences was found in Na+ concentration. Major histopathological effects of atrazine on the gills were hyperplasia and thickening of the filaments, separation of the pavement cells of the lamellae epithelium from the pillar cells and swelling of the epithelial cells. Results of the present study showed that atrazine could affect the ion composition of the body, and caused major damages in gill epithelium even at sublethal concentration and acute exposure, but had no effects on the growth parameters

Comparison of antibacterial activities of Ircinia mutans extracts in two different seasons from Kish Island, Persian Gulf, Iran

Sponges, which constitute the phylum Porifera, are the most primitive of the multicellular animals, among all marine organisms screened. Marine sponges produce the largest number of structurally diversified natural products. In this study we investigated in vitro antimicrobial activity of Ircinia mutans collected from the Kish Island in the Persian Gulf against strains of bacteria Escherichia coli (ATCC 15224), Pseudomonas aeruginosa (ATCC 25619), Staphylococcus aureus (ATCC 1764), and Bacillus subtilis spizizenii (ATCC 6633). Diethyl etter, methanol and aqueous extracts of sponge were evaluated by using the Bacterial Broth Dilution Method. The results showed that the aqueous extracts didn’t have any antibacterial activity. Minimum Inhibitory Concentrations (MIC) of the winter diethyl etter extract was 2 mg/ml for E.coli and 20 mg/ml for P. aeruginosa, whereas the summer diethyl etter extract and both of methanol extracts did not show any activity. The MIC and MBC (Minimum Bacterial Concentration) of summer diethyl etter extracts were 2 mg/ml and 3mg/ml against S. aureus; and 5mg/ml and 10mg/ml when tested on B. subtilis. The MIC and MBC of winter diethyl etter extracts were measured as 1.5 mg/ml and 2mg/ml against S. aurous; and 5mg/ml and 10mg/ml when examined on B. subtilis. Summer and winter methanol and aqueous extracts of I. mutans did not show any activity against these bacteria. Therefore secondary metabolite solutions in diethyl etter contain components with antibacterial properties and can be used as antibiotics products

A new method for venom extraction from venomous fish, green scat

Scatophagus argus argus (Green Scat) is a pretty aquarium fish. Its hard spines are venomous and can cause painful injury. In this study 60 specimens of Green Scat were collected periodically from coastal waters of Boushehr (south of Iran) from May 2011 to April 2012. Anatomical features of venomous spines were investigated. Scat venom was extracted from the spines in a new manner for keeping the specimens alive. The nature of venom was tested by SDS-PAGE. Ethical issues and animal welfare principles such as rapid and instantaneous anesthetizing, post operation disinfection and fast recovery of the specimens was practiced in order to minimize the complications. This method enhanced the purity and quantity of venom as demonstrated by 12 separated proteins in electrophoresis. New ethical issues were developed to surviving the specimens and prolong viability as well

Population genetic structure of the white sardine, Sardinella albella, in the Persian Gulf and Sea of Oman by analysis of mitochondrial control region

Several studies on the white sardine: Sardinella albella, have focused on the identification of stock composition and behavior. In this study population genetic structure and historical demography of S. albella along the cost of the Persian Gulf and Sea of Oman were investigated with a 500-bp segment of mt-DNA control region. In total 40 samples were collected from 3 locations: Jask in Sea of Oman, Qeshm in Strait of Hormuz and Lengeh in the Persian Gulf during 2012-2013. 33 haplotype were obtained none of which were presented in all sampling sites. Analysis of molecular variance (AMOVA) indicated low genetic differentiation among regions (F_ST=0.024, p<0.05). The average pair wise differences between regional population were small but significant (0.0158-0.165). Molecular variance explained by differences among three regions was significantly different from zero but the F_ST did not show clear phylogeographic isolation. This observation can support the conclusion that S. albella has a widespread dispersal potential

Extraction and identification of steroids in two species marine algae, Sargassum oligocystum and Nizamudiinia zanardinii in Persian Gulf and Oman Sea

Sargassum oligocystum and Nizamudiinia zanardinii are the most abundant algae distributed in the north of Persian Gulf and Oman Sea. In this study after sampling and preparation of S. oligocystum by Chroform-Etanol (3-1) solvent and N. zanardinii by methanol has been extract. Separation and purification of the compounds was carried out using thin layer, general and inverse column chromatography, Cephadex and high-performance liquid chromatography (HPLC ). Structural elucidation of the constituents was based on the data obtained from HNMR, 13C-NMR, HSQC, HMBC, DEPT and Cephadex LH-20. The steroids compounds separated from above algae were identified as 22-dehydrocholesterol (1) cholesterol (2) fucosterol (3) 29-hydroperoxystigmasta-5,24(28)-dien-3β-ol (4) 24-hydroperoxy-24- vinylcholesterol (5) a mixture of 24(S)-hydroxy-24-vinylcholesterol (6) and 24(R)-hydroxy-24- vinylcholesterol (7) and ostreasterol (8) based on their spectral data and from comparison with those previously reported in the literature