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1.
Effects of Water Hardness and Calcium: Magnesium Ratios on Reproductive Performance and Offspring Quality of Macrobrachium rosenbergii 
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下载免费PDF全文 Kamran Rezaei Tavabe Gholamreza Rafiee Mohammad Mehdi Shoeiry Shadab Houshmandi Michael Frinsko Harry Daniels 《Journal of the World Aquaculture Society》2015,46(5):519-530
This study evaluated the effect of specific calcium and magnesium ratios at two hardness values on reproductive performance and offspring quality of Macrobrachium rosenbergii brood‐females. Hatchery water containing 110.5 mg/L CaCO3 hardness was considered baseline as it has been used successfully to hatch and rear larvae and was used as the control treatment. At each hardness value of 150 and 190 mg/L CaCO3, four experimental water treatments were made in triplicate. Each treatment was adjusted using soluble salts (CaCl2·H2O, MgSO4·7H2O, and MgCl2·6H2O) to provide the hardness and calcium to magnesium ratios of 0:20, 20:80, 50:50, and 80:20 needed. Each of the experimental tanks (140 L) were stocked with six females and one male. The results indicated that both hardness and Ca:Mg ratios affect brood‐female reproductive qualitative parameters such as intermolt period, egg hatchability, egg dry weight, and egg‐clutch somatic index (ESI) parameters (P < 0.05) but not fecundity and eggs per spawn. The results revealed that brood‐females at 150 mg/L hardness showed greater reproductive performance than at 190 and 110.5 mg/L hardness. The findings also demonstrated that the treatment 50Ca50Mg at 150 mg/L hardness with 38.8 mg/L calcium and 12.9 mg/L magnesium had optimum reproductive performance and offspring quality for M. rosenbergii brood‐females. 相似文献
2.
Javanmardi Sina Rezaei Tavabe Kamran Rafiee Gholamreza Moradi Saeed Sivaji Divya 《Aquaculture International》2022,30(4):2145-2163
The aim of this study was to investigate the possibility of improving the growth and physiological indices of plant and fish by adding different levels of ascorbic acid (vitamin C) to water in the aquaponic system using Nile tilapia (Oreochromis niloticus) and saffron plant (Crocus sativus). 240# fish (12.5?±?0.21 gr) and 120# saffron corms (2.8?±?0.12 gr) were randomly assigned to 15 experimental units and underwent treatments of adding 0 (control), 2, 4, 6, and 8 mg L?1 ascorbic acid to water, every 6 days, for 8 weeks. The fish final weight and subsequently other growth performance indices increased in the treatment of 4 mg L?1 vitamin C compared to other treatments (P?≤?0.05). Some growth performances of saffron plants such as saffron production, in treatment of 6 mg L?1, were significantly higher than the control group and reached from 17.34?±?0.27 mg flower?1 in the control group to 25.4?±?1.61 mg flower?1 in treatment of 6 mg L?1. Measuring the serum biochemical parameters of the fish showed that, in the treatment of 8 mg/L ascorbic acid, the cortisol content in the blood reached its maximum (21.49?±?2.42 µg dL?1). The trypsin activity in proximal intestine and mid-intestine significantly increased in treatments of 2, 4, and 6 mg L?1, respectively. The current experiment showed that, by adding 4–6 mg/L ascorbic acid to the aquaponic system water (every 6 days), the optimal levels of Nile tilapia and saffron plant growth performances would occur.
相似文献3.
Morteza Zendehdel Keyvan Hasani Vahab Babapour Sepideh Seyedali Mortezaei Yalda Khoshbakht Shahin Hassanpour 《Veterinary research communications》2014,38(1):11-19
The present study was designed to examine the effects of intracerebroventricular (ICV) injection of Dopamine (10, 20 and 40 nmol), L-DOPA (dopamine precursor; 62.5, 125 and 250 nmol), 6-OHDA (dopamine inhibitor; 75, 150 and 300 nmol), SCH 23390 (D1 antagonist; 2.5, 5 and 10 nmol), AMI-193 (D2 antagonist; 2.5, 5 and 10 nmol), NGB2904 (D3 antagonist; 3.2, 6.4 and 12.8 nmol), L-741 T742 (D4 antagonist; 1.5, 3 and 6 nmol) on food intake in FD3 chickens. At following, birds were ICV injected using 8-OH-DPAT (5-HT1A agonist; 15.25 nmol) and SB242084 (5-HT2C antagonist; 1.5 μg) prior dopamine (40 nmol) injection. Cumulative food intake was determined until 3 h post-injection. According to the results, dopamine significantly decreased food intake in chickens (p?<?0.05). The inhibitory effect of dopamine on food intake was decreased by SCH 23390 pretreatment (P?<?0.05), but AMI-193, NGB2904 and L-741, 742 had no effect on food intake induced by dopamine. In addition, hypophagic effect of dopamine was attenuated by SB242084 (P?<?0.05), but 8-OH-DPAT had no effect. These results suggest that dopamine decrease food intake via D1 receptor and there is an interaction between dopaminergic and serotonergic systems via 5-HT2C receptor in chickens. 相似文献
4.
Potential N2-fixation was investigated in a number of samples representing soils and water courses under the effect of some industrial wastes in Helwan area of Egypt. Microbiological analysis of soil and water samples showed the general enrichment of fungi, actinomycetes and bacteria including N2-fixers. Among asymbiotic N2-fixers, azospirilla compared to azotobacters and clostridia were found to be present with rather higher densities in all samples tested. Generally, the microbial numbers increased by increasing the distance from the Industrial Complex at Helwan, which could be attributed to the high levels of salinity and total heavy metals near the factories. The results indicated that the industrial wastes near the factories exerted inhibitory effects on the acetylenereducing activity in soils, which seriously reduces their biological fertility. Such effects were decreased by getting away from the factories. Significantly negative correlations were recorded between densities of N2-fixers or N2-ase activity and salinity and total heavy metals content in both soil and water samples. 相似文献
5.
Franck Richard Melanie Roy Oula Shahin Christopher Sthultz Myriam Duchemin Richard Joffre Marc-André Selosse 《Annals of Forest Science》2011,68(1):57-68
• Introduction
Millions of hectares of Quercus ilex forests dominate disturbed landscapes in the western part of the Mediterranean basin. Although these forests are very widespread, little is known about the composition and structure of their associated ectomycorrhizal fungal communities. 相似文献6.
7.
Garcia-Barros M Paris F Cordon-Cardo C Lyden D Rafii S Haimovitz-Friedman A Fuks Z Kolesnick R 《Science (New York, N.Y.)》2003,300(5622):1155-1159
About 50% of cancer patients receive radiation therapy. Here we investigated the hypothesis that tumor response to radiation is determined not only by tumor cell phenotype but also by microvascular sensitivity. MCA/129 fibrosarcomas and B16F1 melanomas grown in apoptosis-resistant acid sphingomyelinase (asmase)-deficient or Bax-deficient mice displayed markedly reduced baseline microvascular endothelial apoptosis and grew 200 to 400% faster than tumors on wild-type microvasculature. Thus, endothelial apoptosis is a homeostatic factor regulating angiogenesis-dependent tumor growth. Moreover, these tumors exhibited reduced endothelial apoptosis upon irradiation and, unlike tumors in wild-type mice, they were resistant to single-dose radiation up to 20 grays (Gy). These studies indicate that microvascular damage regulates tumor cell response to radiation at the clinically relevant dose range. 相似文献
8.
Azadeh Azadbakht Amir Reza Abbasi Nourolah Noori Ezzat Rafiee Mojtaba Taran 《Fibers and Polymers》2013,14(4):687-692
The present investigation reports the novel synthesis of CoWO4 nanoparticles@silk fiber under ultrasound irradiation. The effect of temperature, power of ultrasound irradiation and sequential dipping steps in growth of the CoWO4 particles were studied. Results show a decrease in the particles size as the temperature and power of irradiation decreased. The fibers containing CoWO4 nanoparticles were tested for their antibacterial efficacy against E. coli and S. aureus and were found to possess significant antibacterial activity. The results show the CoWO4 nanoparticles@silk with strongest fluorescence characteristics can be obtained in this method. The physicochemical properties of the nanoparticles were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectroscopy. 相似文献
9.
Vahid Nasiri Ali.A.Darvishsefat Reza Rafiee Anoushirvan Shirvany Mohammad Avatefi Hemat 《林业研究》2019,(3):943-957
Temporal land use/land cover (LULC) change information provides a variety of applications for informed management of land resources. The aim of this study was to detect and predict LULC changes in the Arasbaran region using an integrated Multi-Layer Perceptron Neural Network and Markov Chain analysis. At the first step, multi-temporal Landsat images (1990, 2002 and 2014) were processed using ancillary data and were classified into seven LULC categories of high density forest, low-density forest, agriculture, grassland, barren land, water and urban area. Next, LULC changes were detected for three time profiles, 1990–2002, 2002–2014 and 1990–2014. A 2014 LULC map of the study area was further simulated (for model performance evaluation) applying 1990 and 2002 map layers. In addition, a collection of spatial variables was also used for modeling LULC change processes as driving forces. The actual and simulated 2014 LULC change maps were cross-tabulated and compared to ensure model simulation success and the results indicated an overall accuracy and kappa coefficient of 97.79% and 0.992, respectively. Having the model properly validated, LULC change was predicted up to the year 2025. The results demonstrated that 992 and 1592 ha of high and lowdensity forests were degraded during 1990–2014,respectively, while 422 ha were added to the extent of residential areas with a growth rate of 17.58 ha per year. The developed model predicted a considerable degradation trend for the forest categories through 2025, accounting for 489 and 531 ha of loss for high and low-density forests, respectively. By way of contrast, residential area and farmland categories will increase up to 211 and 427 ha, respectively. The integrated prediction model and customary area data can be used for practical management efforts by simulating vegetation dynamics and future LULC change trajectories. 相似文献
10.
Mohammad Navid Forsatkar Gholamreza Rafiee Hamid Farahmand Gonzalo Martínez-Rodríguez 《Journal Of Applied Aquaculture》2017,29(2):183-196
A study was designed to investigate the possible positive prebiotic effects of mannan oligosaccharides (MOS) on growth and reduction of anxiety behaviors in zebrafish (Danio rerio). The experimental diets were supplemented with 0, 2, 4, 6, or 8 g MOS kg?1 and were fed to juvenile fish (0.47 ± 0.017 g) in triplicates for six weeks. Significant differences were found in the final body weight, body weight intake, percent body weight intake, and specific growth rate among treatments. The regression analyses showed that the optimum MOS level was 4–4.1 g MOS kg?1 diet. Fish fed 4 g MOS kg?1 feed showed higher survival than the other treatments. Also, using the novel tank test, fish fed with 4 g MOS kg?1 diet showed lower anxiety by swimming in the upper portion of the tank. The other behavior parameters remained unaffected by the prebiotic. The results indicated the beneficial effect of the prebiotic MOS on growth and partly on welfare of zebrafish juveniles. 相似文献