Effect of dietary estradiol-17β on growth performance, body composition and blood indices in Stellate sturgeon, Acipenser stellatus

This study was investigated the effects of dietary estradiol-17β (E2) on growth, body composition and blood indices in Acipenser stellatus. Fish (40.9 ± 1.1 g average initial weight; n = 60 per group) were fed with three different diets containing 0 (control), 25 and 50 mg kg-1 dietary estradiol contents to apparent satiation for seven months. The results suggested that growth rate were decreased as the E2 level was increased. No significant difference was observed in condition factor among dietary treatments. The highest survival rate was observed in fish fed control diet, but was not significantly different among the treatments (P>0.05). Body composition did not show significant changes among dietary treatments. Number of white blood cells and red blood cells, hemoglobin and hematocrit values were significantly decreased as the E2 levels were raised (P<0.05). Plasma biochemical parameters including glucose, total protein, cholesterol, triglyceride, calcium, and phosphorus levels were dose dependent with the lowest levels in control with the highest levels in fish treated with 50 mg E2. The results of the present study revealed growth suppression of dietary E2 and changes of blood indices with providing some basic information on the effect of estrogen hormone on physiology of sturgeon

The effect of optical spectroscopy on incubation disorders of Iranian Acipenser persicus

Without abstract

Comparative morphology of the sagittal otolith in three species of south Caspian gobies

12 pages, 2 figures, 6 tablesSagittal otolith shapes were investigated in order to identify three sympatric species of south Caspian gobies (Caspian goby Neogobius caspius, deepwater goby Ponticola bathybius and bighead goby Ponticola gorlap). The sagittal otoliths in P. bathybius have a rectangular shape and are thick, whereas in N. caspius they are relatively round and thin. In P. gorlap, otoliths have an elongated shape and are relatively thick. The noticeable difference among the otoliths of the three species is the presence of one anterior and one posterior projection in the otoliths of N. caspius and P. gorlap. Among shape indices, form factor (irregularity of surface area), circularity, aspect ratio and rectangularity are the foremost that indicate interspecific variability. The canonical discriminant analysis correctly classifies 94·7% of the original group cases. The overall analyses show the relevance of applying otolith shape for interspecific distinction of the three species of Caspian gobiesThe authors thank S. Poursaeid for his kind collaboration during this study. We also acknowledge K. Abbasi for his assistance in the identification of fishes. Thanks to S. Shafiei for his assistance in taking photographs of otoliths. We also acknowledge M. Nelson for her assistance in the language editing of this manuscriptPeer reviewe

Antioxidant and vasorelaxant activities of flavonoids from Amygdalus lycioides var. horrida

Amygdalus lycioides var. horrida (Spach) Browicz (Rosaceae), also known as Prunus lycioides (Spach.) Schneid., is an endemic Iranian species of the genus Amygdalus. In Iranian traditional medicine, the aerial parts and roots of A. lycioides are used in the treatment of diabetes. Six flavonoids, i.e. quercetin 3-O-rhamnoside (1), luteolin 7-O-rhamnoside (2), isorhamnetin 3-O-rutinoside (3), kaempferol 3-O-rhamnoside (4), apigenin (5), and naringenin (6), have been isolated from the aerial parts of this plant. The structures of these compounds were elucidated by UV, MS, and NMR spectroscopic data analyses. While the antioxidant activity of these compounds was assessed by the 2,2-diphenyl-l- picryl-hydrazyl (DPPH) assay, the vasorelaxant effect was determined using the rat aortic vascular smooth muscle. Compounds 1-6 displayed significant antioxidant activity, with the RC50 values ranging from 0.0033 to 0.5186 mg/ml. Compound 2 showed a considerable vasorelaxant activity on rat aortic vascular smooth muscle in a dose-dependent manner. © T�BİTAK

Social organization and endocrine profiles of Australoheros facetus, an exotic freshwater fish in southern Portugal

Australoheros facetus is a neotropical cichlid and an exotic species in the Guadiana and Odelouca basins (Southern Portugal). In this research, we aimed to characterize the main behavioural patterns and circulating hormones, 17 beta-estradiol (E-2) for females, and testosterone, 11-ketotestosterone (11KT) and cortisol for both sexes, during the formation of social groups, a crucial step in the life-history of A. facetus. A pair-breeding strategy with territorial behaviour and aggressive interactions was found, with a positive correlation between dominance and size for both sexes. There were no significant differences between non-territorial and territorial individuals in the baseline levels of hormones, but 11KT was higher in males when they became territorial, as E-2 for territorial females, while there was no clear pattern for testosterone. In contrast, cortisol was higher in non-territorial males and correlated negatively with social dominance. These results suggest that size is the main driver for social dominance and that formation of stable hierarchies result in higher circulating 11KT and lowers stress in territorial males. Related to A. facetus' behaviour, aggressiveness and biparental care may be an advantage during the invasion process of A. facetus, facilitating colonization of new habitats.National Council for Technological and Scientific Development of Brazil (CNPq), Program Science without Borders [245971/20122]FCT-Foundation for Science and Technology [UID/Multi/04326/2013, SFRH/BPD/67008/2009]info:eu-repo/semantics/publishedVersio