Ali Reza Shamoradi; Mohammad Ali Salari-Aliabadi; Seiied Mohammad Bagher Nabavi; Ahmad Savari; Abdolali Movahedinia
Volume 11, Issue 2 , November 2012, , Pages 8-15
Abstract
The goals of this study were identification and ecological survey on macrobenthic bivalves in the Khark Island. This study has been done during four seasons through 2010-2011 in five sites around the Khark Island. In each five sites, three separated transects including supralittoral, eulittoral and sublittoral ...
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The goals of this study were identification and ecological survey on macrobenthic bivalves in the Khark Island. This study has been done during four seasons through 2010-2011 in five sites around the Khark Island. In each five sites, three separated transects including supralittoral, eulittoral and sublittoral zones have been selected. At each sampling time and site environmental factors such as temperature, salinity and total organic maters (TOM) have been measured. Collected samples were analysed and according to the results, Maximum and minimum water temperatures have recorded in summer (35.94 ± 0.28) and in winter (18.34 ± 0.39) and the Maximum and minimum rates of salinity have recorded in winter (44.6 ± 0.14) and spring (37 ± 0.18) respectively. Maximum and minimum percentages of total organic maters (TOM) have observed in summer (9.63 ± 0.71) and winter (3.39 ± 0.15) respectively. Twelve bivalve species belonging to seven families were identified that are: Barbatia lacerate, Pinctada radiate, Ostrea sp.1, Crossostrea gigas, Sacosstrea cucullata. Diplodonta ravaiyensis, Venus sp.1, Circentia callypyga, Callista sp.1, Gari roseus, Tellina capsoides, Angulus adensis. The maximum and minimum density and distribution have been found in spring and summer respectively. In our study the most frequent bivalve species in all seasons was Barbatia lacerate.
Aliakbar Hedayati; Vahid Yavari; Abdolali Movahedinia; Hossein Pashazanosi
Volume 10, Issue 1 , September 2012, , Pages 44-52
Abstract
Successful management of sturgeon population requires knowledge of stock composition with regard to sex and gonadic stage. Measurement of sex steroid concentration has proven to be a reliable and less invasive method in compare to convention methods. In this study we have examined the possible role of ...
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Successful management of sturgeon population requires knowledge of stock composition with regard to sex and gonadic stage. Measurement of sex steroid concentration has proven to be a reliable and less invasive method in compare to convention methods. In this study we have examined the possible role of plasma testosterone (T), estradiol (E2), progesterone (P), cortisol (C) and morphometric parameters as indicators of sex and stage of gonadal development in immature (4-5 years old) Great sturgeon cultured in brackish water. Biometry of fishes, blood sampling from caudal vein was performed every three month and plasma was frozen until analyses. Glucose was measured with auto analyser, calcium and magnesium with spectrophotometer and sodium and potassium with film photometer, Hormone levels were measured by radio immunoassay (RIA). Histological preparation was stained with hematoxylin and eosin. In sex determination, result show that total length (L) and weight (W) had no significant elevation in different sexes and can not be used as an indicator sex determination. Among hormones only T had significant elevation, so it could be stated that level of T in immature Great sturgeon could be used to identify sex. In case of gonadic stage result show that total L and W just in male had significant correlation with gonadal stage and among hormones just T in male and C in female had significant correlation. So it could be concluded that in male and female respectively based on T and C measurment gonadic stage in immature Grate sturgeon could be identified