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Sakineh Shirvan Bahram Falahatkar Hamid A. Noveirian Alireza Abbasalizadeh 《Aquaculture Research》2020,51(1):282-291
An 8‐week study was applied to evaluate the effects of feed restriction and starvation on growth, proximate composition, haematological and biochemical factors in juvenile Siberian sturgeon Acipenser baerii with an average weight of 54 ± 0.6 g. Fish were randomly divided into nine indoor tanks (1,050 L volume) with 30 fish per tank in a flow‐through system at 18 ± 0.4°C. Three feeding strategies were considered: I) fed at satiation (F), II) restricted feeding at the rate of 1% body weight per day (R) and III) starvation (S) each with 3 replicates. Fish were fed with commercial pellets 4 times daily, but no feed was considered for S group throughout the trial. Basal level at the start, 4 and 8 weeks after initiation of the experiment, blood samples were taken from 5 fish/tank to measure the haematological and biochemical parameters. Moreover, growth performance was recorded every 2‐week interval. At the end of the experiment, the growth parameters and proximate composition were significantly different among the treatments. As expected, the highest weight (164.7 ± 2.1 g) was observed in F group compared to R (101 ± 1.7 g), or S (42.4 ± 0.8 g) groups. The highest (12.07 ± 0.14%) and lowest (5.37 ± 0.42%) fat contents were observed in F and S groups, respectively, while the protein was not affected in R group compared with F group. In addition, most haematological and biochemical indices of Siberian sturgeon were affected by starvation at week 4 and 8, while few changes were observed in restricted feeding. The highest mean corpuscular volume, mean corpuscular haemoglobin, plasma total protein, cholesterol and triglyceride was found in S group, while the lowest value of plasma glucose was observed in this group. It can be concluded that Siberian sturgeon adjusts the physiological condition in short‐term (4 weeks) feed restriction using stored metabolites to have basal metabolism and due to this, a short period of feed restriction strategy recommends to the optimum nutritional management of Siberian sturgeon to cost‐saving during unsuitable conditions. 相似文献
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Growth,development and behaviour of Persian sturgeon Acipenser persicus larvae in different light regimes 
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下载免费PDF全文 Bahram Falahatkar Samaneh Poursaeid Iraj Efatpanah Bahman Meknatkhah 《Aquaculture Research》2017,48(12):5812-5820
The effects of five different light regimes on growth performance and behaviour of Persian Sturgeon larvae were examined. Larvae were reared under five different photoperiods (24L, 12L:12D, 16L:8D, 8L:16L and 24D), from hatching (25.8 ± 8.1 mg; 12 ± 0.6 mm) to 28 days post‐hatch (dph). Except the last week, there was no significant difference in growth parameters among the experimental groups. Growth performance significantly improved in larvae reared under a continuous light regime. The highest final length (34.5 ± 1.7 mm) was measured in 24L and the lowest one (29.5 ± 0.4 mm) in the constant darkness. Relative to other experimental groups, the continuous darkness had a retarding impact on the yolk sac absorption and swarming behaviour. Among the whole body compositions, the lowest body moisture content was measured in the continuous light group. Persian Sturgeon pre‐larvae and larvae were not completely dependent on light regimes (in 1–21 days), whereas on the basis of measured parameters (total length, wet and dry weight and digestive fullness index) a continuous light regime played a decisive role on growth performance beyond 21 dph. 相似文献
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Vahid Mahdavi Hooshang Rafiee-Dastjerdi Asadollah Asadi Jabraeil Razmjou Bahram Fathi Achachlouei Shizuo George Kamita 《American Journal of Potato Research》2017,94(6):647-657
Phthorimaea operculella (Zeller) is one of the most common insect pests of cultivated potato in tropical and subtropical regions. In this research, a potential strategy to improve the insecticidal activity of plant essential oils for the effective management of P. operculella was studied. The insecticidal and residual effects of nanofiber oil (NFO) and pure essential oil (PEO) of Cinnamomum zeylanicum were assessed on PTM under laboratory conditions. The nanofibers were made by the electrospinning method using polyvinyl alcohol (PVA) polymer. The morphological characteristics of the nanofibers were evaluated by scanning electron microscopy and Fourier transform infrared spectroscopy. The chemical constituents of cinnamon essential oil (EO) were detected by GC/MS. Fumigant toxicity of NFO and PEO were evaluated on different growth stages (egg, male and female adults) of P. operculella. SEM and FTIR analyses confirmed the presence of EO on the nanofiber structure. The yield of the EO from C. zelanicum on the nanofibers was 1.86%. GC/MS analysis showed that cinnamaldehyde was the primary constituent (69.88%) of cinnamon EO. LC50 values of C. zelanicum EO and NFO were 4.92 and 1.76 μl/l air for eggs, 0.444 and 0.212 μl/l air for female adults, and 0.424 and 0.192 μl/l air for male adults, respectively. Fumigant bioassays revealed that NFO was more toxic than C. zeylanicum oil against at all stages of P. operculella. The residual effect of PEO and NFO was evaluated against the egg stage of the P. operculella. NFO lost insecticidal effectiveness 47 days after application, while the efficacy of PEO decreased 15 days after application. Our results suggest that NFO of C. zeylanicum can be used as an effective new tool for the management of P. operculella. 相似文献
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Gender identification of great sturgeon during different life stages was conducted using morphology, sex steroid concentrations, histological and endoscopic techniques. One hundred and forty great sturgeons from two sturgeon farms at ages between 3‐16 years were selected for examination. Most of the morphological indices showed no significant sex‐related differences except for the ratio of fork length to distance of snout to anterior of dorsal fin (PD). The urogenital opening had no difference in shapes for both sexes. Mean sex steroid concentrations showed no significant difference in levels of testosterone, estradiol and progesterone between males and females in the stage II of maturity. 95.8% of fish were correctly sexed using endoscopy at this stage. Histological investigation indicated the ovaries of 3‐ to 9‐year‐old females were at the different stages of pre‐vitellogenic, and most males were at the early spermatogenesis for age 3. The result of this study suggests that endoscopy is a reliable tool for sex and stage determination after the age of 3 years. This method is useful in providing a quick discernment of sexes and stages compared with utilizing morphometric and blood indices. Direct observation of gonads can give us important information about the gonadal and maturity stages in sturgeon aquaculture and wild population management, with minimal damage or stress to this endangered species. 相似文献
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Seyed Daryoush Moghaddas Asghar Abdoli Bahram H. Kiabi Hossein Rahmani Lorenzo Vilizzi Gordon H. Copp 《Fisheries Management and Ecology》2021,28(1):28-39
Risk screening tools play a crucial role in identifying potential high-risk non-native (NN) fish species. In this study, potentially invasive NN fish species in the Anzali Wetland Complex (AWC), which is located on the south coast of the Caspian Sea (Iran), were identified using the Aquatic Species Invasiveness Screening Kit (AS-ISK). Twenty-nine freshwater fish species were screened of which 13 exist in the AWC and 16 in close proximity to it (“horizon” species). Receiver operating characteristic curve analysis showed that AS-ISK could discriminate reliably between non-invasive and invasive fish species for the AWC. Mean threshold scores were 3.25 for the Basic Risk Assessment (BRA) and 11.75 for the BRA + CCA (BRA + Climate Change Assessment), and these, respectively, classified 89.7% and 86.2% of the species as high risk. The CCA resulted in an increase in the BRA scores for 86.2% of the species, suggesting the need to account in future NN species management for a likely increased invasiveness of those species under future climate conditions. These results suggest that AS-ISK could prove an effective tool for identifying potentially invasive NN freshwater fishes in other wetlands of the Caspian Sea basin. 相似文献
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Abstract An 8-week feeding experiment was conducted to investigate the effect of dietary vitamin E on the physiological response to handling stress in juvenile beluga Huso huso. Fish were fed six experimental diets supplemented with 0, 25, 50, 100, 200, or 400 mg Dl-all-rac-α-tocopherol acetate/kg diet. At the end of the experiment, the fish in each tank were subjected to acute handling and air exposure stress. Cortisol and glucose were measured as the primary hormonal and secondary metabolic responses to the stressors, both before and 3 h after application of the stressors. The growth parameters and feed utilization rates were significantly lower in fish fed the diet not supplemented with vitamin E than in fish fed diets supplemented with vitamin E. Cortisol concentration was not affected by dietary treatment but glucose concentration was. Fish fed vitamin E at 0, 25, 100, and 400 mg/kg diet had higher concentrations of glucose than those fed vitamin E at 50 and 200 mg/kg. However, fish fed diets with 50 and 200 mg/kg exhibited higher growth rates. These results indicate that dietary vitamin E has some effect on plasma glucose but no effect on plasma cortisol. In general, when the stressors were applied to belugas, the glucose and cortisol responses were relatively low. This may be due to higher resistance and lower physiological responses to these types of stressors by this species or by chondrosteans in general. Received January 10, 2011; accepted August 4, 2011 相似文献
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Zeynab Shahabzadeh Bahram Heidari Ali Dadkhodaie 《Journal of Crop Science and Biotechnology》2013,16(3):209-217
Due to its vegetative reproduction, saffron has a narrow genetic base and induced in vitro variations provide opportunities for expanding new cultivars. The objectives of this study were to evaluate sodium azide-induced variations in saffron’s corm culture in order to increase salt tolerance and pharmaceutical ingredients. Corm explants from the well-known ecotypes, Estahban and Kashmar, were subjected to various concentrations of sodium azide (NaN3) (0.09, 0.12, and 0.22 mg L?1) and NaCl (1.5, 2.5, and 4.0 dS equivalent to 0.07, 0.12, and 0.20 g NaCl in 100 mL water) in Murashige and Skoog medium supplemented with 1 mg L?1 2-4-D, 1 mg L?1 BAP, and 30 g L?1 sucrose and in a second pot culture experiment. The active pharmaceutical ingredients (crocin, picrocrocin, and safranal) were measured by high-performance liquid chromatography (HPLC). Variations in sodium azide-treated plants were more broadened for callus fresh weight (0.57–7.57 g), embryo weight (1.24–10.29 g), and regenerated seedlings (3.0–21.25) compared with those (0.12–3.77 g, 0.56–4.56 g, and 0.25–11.50, respectively) that were not treated with sodium azide. Under 0.20% salt, flowering failed in some of plants developed from sodium azide-untreated corms. HPLC analysis indicated wider ranges for crocin (11.92–18.03 mg g?1), picrocrocin (8.99–14.76 mg g?1), and safranal (2.13–7.36 mg g?1) in sodium azide-treated plants compared to the ranges (0.0–16.1, 0.0–12.5, and 0.0–6.66 mg g?1, respectively) in untreated plants. From a breeding perspective, induced variations found in this study would be useful to improve saffron’s quality and salt tolerance. 相似文献