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Feeding frequency and stocking density are important factors affecting growth and maturation of cultured fishes. The aims of this investigation were to determine the effects of stocking density (10, 20, 30 and 40 fish per aquarium) and feeding frequency (2, 3 and 4 times per day) on growth parameters and hematocrit of the Rutilus rutilus caspicus. The experiment was continued for 45 days in two replicates. The results of this study showed that growth parameters, including weigh gain (WG), feed conversion ratio (FCR) and specific growth rate (SGR) were affected significantly by stocking density (P<0.05), but not significantly affected by feeding frequency (P>0.05). The highest WG and SGR were recorded with the lowest stocking density (10 fish / aquarium). The least FCR was obtained in density of 10 fish/aquarium, FCR value was significantly higher with high stocking density (P<0.05). Also, interactions between stocking density and feeding frequency were no significant on growth parameters (P>0.05). Density and feeding frequency hand no significant effect of hematocrit concentration (P>0.05). On the other hand, interactions between stocking density and feeding frequency significantly affected hematocrit levels (P<0.05). The lowest level of hematocrit was observed in density of 10 fish/aquarium at two times / day feeding frequency. The results of this study indicated that density is significantly affected the growth, but increasing of feeding frequency there is not effect on growth in the Rutilus rutilus caspicus.
 

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The aim of this study was to evaluate the antibacterial activity of the water extracts of three species of Salvia (S. perspolitana, S. palaestina, S. bracteata) on Staphylococcus aureus, Escherichia coli and Pseudomonas aeroginosa. The antibacterial activity of water extracts of the studied species on the bacterial strains was examined using well diffusion method and minimum inhibitory concentration (MIC). Results showed that only S. bracteata formed growth inhibitory zone (9 mm) on Staphylococcus aureus. The extracts of all three plants formed growth inhibitory zone on E.coli and P. aeroginosa. The extract of S. bracteata was more effective than that of the other species. Results for MIC also showed that the extracts of S. perspolitana had the lowest effect on St. aureus and its MIC was observed in a concentration of 1024 µg/ml. The extracts of this species had the inhibitory effect in a concentration of 256 µg/ml. The uppermost inhibitory effect was provided by the extract of S. bracteata, since the minimum inhibitory concentration of this species for S. aureus was equal to 64 µg/ml; and for the other two bacteria, it was equal to 128 µg/ml. The extracts of S. palaestina had the lowest effect on S. aureus and its MIC was observed in a concentration of 1024 µg/ml. The extracts of this species had an MIC equal to 512 µg/ml for the other two bacteria. It was concluded that S. bracreata could be considered a suitable species with anti-bacterial activities in future researches.
 
 
 

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Malathion is one of the commonest type of organophosphate insecticide whose toxicity in human body is mainly considered to result from the induction of oxidative stress. The aim of this study was to investigate the antioxidant effect of Quercetin, a flavonoid compound, on the spatial memory and oxidative stress parameters during Malathion poisoning in male Wistar rats. This study was performed on nine groups, each of which consisted of eight male rats. Three days after intra-peritoneal injection of Quercetin, Malathion or a combination of these two drugs, the Moris Water-Maze apparatus was used to measure spatial memory parameters. The hippocampus was sampled and the oxidative stress parameters were measured in this area. Intra-peritoneal injection of Malathion (100 and 200 mg/kg) significantly reduced spatial memory parameters (P<0.01) and induced oxidative stress (P<0.001), whereas intra-peritoneal injection of quercetin (50 mg/kg) improved spatial memory in Malathion-poisoned experimental rats (P<0.05). Also, oxidative stress parameters in Malathion-treated groups showed a significant reduction in quercetin treatment (P<0.01). Quercetin was observed to restore the function of spatial memory and the level of oxidative stress parameters of the treated groups with Malathion to the normal level.