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61.
Ali AI-MAKTOUMI ;Said A-ISMAILY ;Anvar KACIMOV ;Hamed AI-BUSAIDI ;Said AI-SAQRI ;Mansour AI-HADABI 《干旱区科学》2014,(6):690-703
Interaction between soil pedogenesis, subsurface water dynamics, climate, vegetation and human ingenuity in a desert environment has been found to result in a unique ecohydrological system with an essentially three dimensional sedimentation structure in the bed of a recharge dam in Oman. A 3-D array of silt blocks sandwiched by dry sand-filled horizontal and vertical fractures was studied in pot experiments as a model of a natural prototype. Pots are filled with a homogenous sand-silt mixture(control) or artificially structured(smart design, SD) soil substrates. Rhodes grass and ivy(Ipomea, Convolvulaceae) were grown in the pots during the hottest season in Oman. Soil moisture content(SMC) was measured at different depths over a period of 20 days without irrigation. SD preserved the SMC of the root zone for both ivy and grass(SMC of around 25%–30% compared to 10% for control, 3 days after the last irrigation). Even after 20 days, SMC was around 18% in the SD and 7% in the control. This, similar to the case of a natural prototype, is attributed to the higher upward capillary movement of water in control pots and intensive evaporation. The capillary barrier of sand sheaths causes discontinuity in moisture migration from the micro-pores in the silt blocks to sand pores. The blocks serve as capillarity-locked water buffers, which are depleted at a slow rate by transpiration rather than evaporation from the soil surface. This creates a unique ecosystem with a dramatic difference in vegetation between SD-pots and control pots. Consequently, the Noy-Meir edaphic factor, conceptualizing the ecological impact of 1-D vertical heterogeneity of desert soils, should be generalized to incorporate 3-D soil heterogeneity patterns. This agro-engineering control of the soil substrate and soil moisture distribution and dynamics(SMDaD) can be widely used by desert farmers as a cheap technique, with significant savings of irrigation water. 相似文献
62.
63.
Effect of three natural phytochemicals supplementation on growth performance,testosterone level and feed utilization of Nile tilapia (Oreochromis niloticus) 下载免费PDF全文
An 84‐day feeding experiment was conducted to determine the effects of dietary ginseng extract (GE), tribulus extract (TE) and date palm pollen grains (DPPG) on growth, testosterone level and nutrient utilization of Nile tilapia, Oreochromis niloticus, fingerlings. Seven experimental treatments were conducted in three replicates: control fed basal diets without any supplementations, GE0.2 (supplemented with 0.2 g GE/kg diet), GE0.4 (supplemented with 0.4 g GE/kg diet), TE0.6 (supplemented with 0.6 g TE/kg diet), TE1.2 (supplemented with 1.2 g TE/kg diet), DPPG3 (supplemented with 3 g DPPG/kg diet) and DPPG6 (supplemented with 6 g DPPG/kg diet). The results indicated that all dietary phytochemicals significantly increased growth compared to the control. Plasma testosterone levels were improved by 86.27%, 64.58%, 57.35% and 24.58% with TE1.2, GE0.4, TE0.6 and DPPG6, respectively, more than the control. The relationship between testosterone and final body weight showed a significant simple linear regression with a positive correlation. The nutrient utilization imprxoved with higher doses of phytochemical supplementations. Moreover, protein content increased and ether extract decreased with phytochemical supplementation. The present results concluded that higher doses of GE, TE and DPPG could be used as growth promoters and testosterone boosters for Nile tilapia fingerlings. 相似文献
64.
M. Mansour 《Journal of pest science》2010,83(3):243-249
The sensitivity of the Mediterranean flour moth, Ephestia kuehniella, eggs in different stages of development to gamma irradiation was studied and the acceptability of irradiated eggs by Trichogramma cacoeciae females was examined. Eggs ranging in age from 1–24 to 49–72 h were exposed, at 24 h intervals, to gamma radiation dosages
ranging from 25 to 400 Gy and effects of gamma radiation on egg hatch and adult emergence was investigated. In addition, the
developmental rate of immature stages (larvae and pupae), resulting from irradiated eggs, to the adult stage was examined
and the acceptance of irradiated eggs to T. cacoeciae females was evaluated. Results showed that the radio-sensitivity of E. kuehniella eggs decreased with increasing age. Egg hatch in 1–24-h-old eggs was significantly affected at 25 Gy dose and at 75 Gy dose,
no egg hatch was observed. When irradiating 25–48-h-old eggs, however, egg hatch was less than 5% at 100 Gy dose, and eggs
49–72-h-old were more resistant; 50 Gy had no significant effect on egg hatch and 300 Gy did not completely prevent it. Irradiation
also negatively affected survival to the adult stage. When 25–48-h-old eggs were irradiated, survival to the adult stage was
completely prevented at 75 Gy dose and no survival was observed beyond 100 Gy dose in 49–72-h-old eggs. In addition, the rate
of development of immature stages resulting from irradiated eggs was negatively affected. While more than 97% of control moths
emerged within 30 days, this ratio decreased to 53 and 69% in 1–24 and 25–48-h-old eggs exposed to 25 Gy dose. Furthermore,
irradiation positively affected the degree of acceptance of eggs to parasitization; irradiated eggs (≤49-h-old) were more
acceptable to T. cacoeciae than cold-treated ones. 相似文献
65.
Lamiaa A. Shaala Diaa T. A. Youssef Jihan M. Badr Mansour Sulaiman Alaa Khedr 《Marine drugs》2015,13(4):1621-1631
In a continuation of our efforts to identify bioactive compounds from Red Sea Verongid sponges, the organic extract of the sponge Suberea species afforded seven compounds including two new dibrominated alkaloids, subereamollines C and D (1 and 2), together with the known compounds aerothionin (3), homoaerothionin (4), aeroplysinin-1 (5), aeroplysinin-2 (6) and a revised subereaphenol C (7) as ethyl 2-(2,4-dibromo-3,6-dihydroxyphenyl)acetate. The structures of the isolated compounds were assigned by different spectral data including optical rotations, 1D (1H and 13C) and 2D (COSY, multiplicity-edited HSQC, and HMBC) NMR and high-resolution mass spectroscopy. Aerothionin (3) and subereaphenol C (7) displayed potent cytotoxic activity against HeLa cell line with IC50 values of 29 and 13.3 µM, respectively. In addition, aeroplysinin-2 (6) showed potent antimigratory activity against the human breast cancer cell line MDA-MB-231 with IC50 of 18 µM. Subereamollines C and D are new congeners of the previously reported compounds subereamollines A and B with methyl ester functionalities on the side chain. These findings provide further insight into the biosynthetic capabilities of members of the genus Suberea and the chemical diversity as well as the biological activity of these compounds. 相似文献
66.
Effects of dietary essential amino acid deficiencies on the growth performance and humoral immune response in silvery‐black porgy (Sparidentex hasta) juveniles 下载免费PDF全文
Morteza Yaghoubi Mansour Torfi Mozanzadeh Jasem G. Marammazi Omid Safari Enric Gisbert 《Aquaculture Research》2017,48(10):5311-5323
A 6‐week feeding trial was conducted for determining the effects of dietary essential amino acids (EAA) deficiencies on growth performance and non‐specific immune responses in silvery‐black porgy juveniles (4.7 ± 0.1 g initial weight). Eleven isoproteic (ca. 47%) diets were formulated including a control diet containing the optimum quantity of EAA, and ten EAA‐deficient diets. All diets contained 36% fish meal and 18.5% crystalline EAA and non‐essential amino acids (NEAA) as the main source of dietary proteins. All the EAA and NEAA incorporated in the crystalline amino acids mixture of the control diet simulated the amino acids profile of the fish meal. The other 10 EAA‐deficient diets were formulated by the deletion of each of the 10 EAA (crystalline form) from the control diet and replaced by a mixture of NEAA for the adjustment of dietary nitrogen contents. At the end of the experiment, fish fed with threonine‐deficient diet showed the lowest survival rate (p < .05), whereas growth performance decreased in fish fed all EAA‐deficient diets, although the reduction in body growth varied depending on the EAA considered. Plasma total protein decreased in all experimental groups except for fish fed the phenylalanine‐deficient diet. Fish fed with arginine‐ and lysine‐deficient diets had the lowest plasma C3, C4, lysozyme, total immunoglobulin and total superoxide dismutase activity (p < .05). Present results indicated that lysine, methionine and threonine were the most limiting EAA in terms of growth performance; however, arginine, threonine and lysine were the most limiting EAA for innate immunity responses in silvery‐black porgy juveniles. 相似文献
67.
Farzaneh Noori Naser Agh Fatemeh Jafari Reza Jalili Enric Gisbert Mansour Torfi Mozanzadeh 《Aquaculture Nutrition》2019,25(5):1050-1062
The influence of dietary fish oil (FO) substitution with blends of vegetal oils (VO: canola, linseed, olive, sunflower, corn and coconut oils) in plant protein‐rich diets on reproductive performance and fatty acid dynamics of embryos was evaluated in female rainbow trout (Oncorhynchus mykiss) brooders (1.8 ± 0.1 kg). Four diets were formulated in which 20% (FO80/VO20), 50% (FO50/VO50), 75% (FO25/VO75) and 100% (VO100) of FO were replaced by mixture of VO. The above‐mentioned diets were administered for a short period prior to spawning (3 months). Fish fed the VO100 had the lowest fertilization rate (81.3 ± 2.3), whereas brooders fed the FO80/VO20 diet had the lowest survival rates at eyed embryo stage (83.7 ± 1.6%) and hatching rate (79.9 ± 3.1%). The fatty acid dynamics of embryos were not only affected by embryonic developmental stages, but also they were influenced by the dietary fatty acid profile. Our study confirmed that using blends of different VO sources and FM residual fat in the FO25/VO75 for the short‐term period prior to spawning seemed to be a good strategy in terms of successful reproduction for sparing high levels of FM and FO in diet of O. mykiss brooders. 相似文献
68.
Rezvan Tamadoni Mahmoud Nafisi Bahabadi Vahid Morshedi Dara Bagheri Mansour Torfi Mozanzadeh 《Aquaculture Research》2020,51(4):1437-1445
An 80‐day feeding trial was conducted to evaluate the influence of different short‐term fasting and re‐feeding strategies on growth and physiological responses in yellowfin seabream, Acanthopagrus latus (2.4 ± 0.2 g) fingerlings. The fish were subjected to four different feeding regimes, and the control group fed four times daily to apparent satiation throughout the whole feeding period, while the other three groups were deprived for 2, 4 and 8 days followed by 8, 16 or 32 days of re‐feeding (F2R8, F4R16 and F8R32, respectively) in repeated cycles for 80 days. The fish in the control and F2R8 groups had the highest and the lowest total length, respectively (p < .05). Moreover, fish exposed to F4R16 had the highest hepatosomatic indices, while control fish had the lowest hepatosomatic indices (p < .05). Fish in the F2R8 group relatively had higher catalase and glutathione‐S‐transferase activities than other groups (p < .05). Furthermore, total protease, α‐amylase and alkaline phosphatase activities in the F4R16 and F8R32 were higher than the F2R4 and control groups (p < .05). Overall, this study showed that compensatory growth in weight and length and digestive enzyme activities were observed in the F4R16 and F8R32; however, the increase in the activity of antioxidant enzymes in the F8R32 group indicated that oxidative stress remained after 80 days of re‐feeding in the liver. 相似文献
69.
Naser Agh Mansour Torfi Mozanzadeh Fatemeh Jafari Farzaneh Noori Reza Jalili 《Aquaculture Research》2020,51(3):918-931
A 90‐day feeding trial was carried out to examine the influence of fish oil (FO) substitution with blends of vegetable oils (VOs) on reproductive efficiency of female brooders and fluctuation in fatty acid (FA) profile of embryos in Oncorhynchus mykiss. A basal diet was formulated in which 20% (80FO/20VO), 50% (50FO/50VO), 75% (25FO/75VO) and 100% (100VO) of FO were replaced by mixture of VO. Reproductive performance of brooders was not affected by drastic alternations in FA profile of diets. The level of saturated and monounsaturated FAs (MUFAs) significantly increased, whereas the levels of long‐chain polyunsaturated FAs (LC‐PUFAs), mainly docosahexaenoic acid, profoundly decreased during embryogenesis. The concentrations of MUFA and n?6 PUFA increased in the eggs with increasing the incorporation of VO mixture in diets; however, the concentration of LC‐PUFA and n?3/n?6 PUFA ratio decreased. Haematological parameters and humoral immune responses including total immunoglobulin content, lysozyme and alternative complement pathway activities in brooders fed with the experimental diets did not statically different. In summary, incorporating mixture of various VO sources especially linseed and sunflower oils as good sources of α‐linolenic and linoleic acids, respectively, along with low levels of residual fat from fish meal in diet suggested a good strategy for providing the appropriate essential FA requirements of O. mykiss brooders for their successful reproduction. 相似文献
70.