Desert Research Center

Cairo, Egypt

Desert Research Center

Cairo, Egypt
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Twenty four non-lactating goats (Age=3.5±0.08 years; Balady goats, n=12 and Shami goats, n=12) were used to evaluate the effects of long-term nutrient restriction on digestion and energy utilization. Six animals of each goat breed were fed a concentrated mixture and alfalfa hay diet (50:50 as DM basis) to meet metabolizable energy (ME) of maintenance (MEm, CON). The other six animals were fed 50% of this amount relative to actual BW (RES). Animals were individually housed for a 90-day period and then moved to metabolic cages in two sets of 12 animals each, three per treatment and breed for each set. Total Energy expenditure (EE) was estimated by a heart rate (HR) monitor for 48 h after its individual calibration by oxygen consumption with a face mask open-circuit respiratory system. Body weight and digestibility were negatively affected by long-term restricted feeding, without differences in digestibility between goat breeds. Energy expenditure was greater for CON vs. RES (417 vs. 355 kJ/kg BW0.75/day respectively, P<0.001) and lower for Balady goats compared to Shami goats, particularly in terms of RES intake treatment (312 vs. 399 kJ/kg BW0.75/day respectively, P<0.01). As a result, the energy balance (EB) was similar for both goat breeds on treatment CON, while it was greater (P<0.05) for Balady goats than Shami goats when they received RES treatment (-133 vs. -208 kJ/kg BW0.75/day respectively, P<0.01). In conclusion, Balady goats, but not Shami goats, have the ability to reduce their EE in order to improve their EB as a mechanism of adaptation when their ME intake is restricted below MEm requirements. © 2016 Elsevier B.V.

Elsheikh A.E.,Desert Research Center
Environmental Earth Sciences | Year: 2015

El Farafra Oasis is included in the New Valley Project which started in the 1960s. This project is based exclusively on groundwater of the well-known Nubian Sandstone aquifer (NSA). The hydraulic head drawdown problem in Farafra Oasis constitutes a big problem because it threatens the availability of the only water source in the Oasis. Hydrogeologically, Farafra Oasis belongs to the huge, artesian, unrenewable fossil water Nubian from sandstone aquifer. The problem began to appear at the end of the 1990s instantaneously with increased drilling of deep water wells. Huge quantities of water (267 million m3) are derived from the aquifer every year. Hydraulic head depression cones are formed around the main reclamation areas where the groundwater surface lowered by 35 m below the ground surface. Numerical modeling was used to investigate the hydrodynamic impacts of the present and planned groundwater extraction on the groundwater levels besides the possible means of mitigating the continuous decrease of the groundwater levels. The aquifer simulation indicated that there is a significant head decline of the groundwater, particularly in the first productive zone. Four scenarios were applied to signify the present and future development plans for the next 20 years, i.e., year 2033. Applying the present conditions reveal that heads are more declined than now. Another 30 and 17.8 m in the first and second productive zones, respectively, are expected to be added to the present groundwater drawdowns. Groundwater is expected to decline significantly if the pumping rates are to be increased by 50 % in response to natural development of the agricultural society and continuous need to more cultivation lands. Groundwater heads are expected to be lower by about 40 m in the first productive zone and 24 m in the second productive zone. The third plan examines the impact of reducing the pumping rate by about 25 % on groundwater levels by applying recent irrigation techniques as drop and sprinkler irrigation methods instead of the presently used flood irrigation. In this case, simulated drawdowns are expected to decline, and the maximum drawdowns recorded are 19 and 10 m through the next 20 years in the first and second productive zones, respectively. To mitigate the groundwater level deterioration, the study suggests the reduction of pumping rates by about 20 % by applying the recent irrigation techniques besides reclamation of about 11,000 feddan (4620 hectare) to accommodate the increasing population and need of cultivation lands in the Oasis in the next 20 years. According to plan, the simulated groundwater levels are expected to decrease by about 20.3 and 12 m at the end of the simulation period (year 2033). This means that the rate of head decline is lowered to about 1 m/year for the first productive zone and 0.6 m/year for the second productive zone with the increase in the cultivation area by about 16 %. Therefore, the study recommends the fourth plan to manage the groundwater resource in Farafra Oasis. © 2015, Springer-Verlag Berlin Heidelberg.

The northwestern coast of Egypt represents one of the highest-priority regions for future development. Two contiguous basins were chosen from the northwestern coast for this research: El Zarraqa and El Harraqa basins. The main objective of the present study is to provide geomorphologic and geological data in order to work on the water potentiality development in the study area. The obtained data through the present study reveal that, although the two studied basins are close to each other, they are not compatible with all features. The morphometric parameters reveal that the studied basins have opportunities for surface runoff occurrence and also for groundwater recharge through infiltration process. The geology of the study area is dominated by sedimentary rocks of Tertiary and Quaternary ages. The study area has favorable conditions for groundwater accumulation, where this area receives an average annual precipitation of 151.95 mm, which provides the opportunity for groundwater recharge. The hydrogeological investigations reflect that two groundwater aquifers (Middle Miocene and Pleistocene) are recorded in the El Harraqa basin, and only the Middle Miocene aquifer is recorded in the El Zarraqa basin. The Middle Miocene aquifer needs more hydrogeophysical investigations to explore its potentialities where its rocks have a wide distribution and are mainly fractured. The difference in groundwater salinity in both aquifers accompanied by different hydrogeologic data confirms that the carbonate aquifer in the studied basins is heterogeneous and has anisotropic characters. The current research set up a proposed plan which includes multiactivities for the protection and development of the water resources. © 2014, Saudi Society for Geosciences.

Abou-Shady A.,Desert Research Center
Electrochimica Acta | Year: 2016

Reclaiming salt-affected soil in arid and semi-arid countries is currently considered a substantial challenge because of water supply deficiencies. Traditionally, salts are removed from soil using either continuous or intermittent washing, which consumes considerable amounts of water. Our motivation for this study is to develop a process for decreasing the reclamation period and total amount of water, and improving the sustainability of reclamation. Recently, we have developed a new generation of soil electro-remediation techniques known as the perforated cathode pipe soil electrokinetic remediation (SEKR) system (PCPSS) for heavy metal removal. PCPSS was investigated for reclaiming salt-affected soils collected from the El-Sallam canal region Egypt. In the present study, enhancement of Na+ removal was firstly investigated using a Taguchi Approach orthogonal array (L9OA). The results indicated that the influential factors improved Na+ removal in the following order: cathode pipe operating time > voltage > cathode gap > hydrostatic head; additionally, the vertical removal above the cathode gap was operating time > hydrostatic head > voltage > cathode gap. A confirmation experiment demonstrated that Mg2+ removal was as high as 41.7% followed by Na+ with 23% removal. Ca2+ removal was the lowest (6.6%), likely due to the formation of insoluble CaSO4. K+ also showed low removal (8.4%), likely because of its comparatively low concentration. The removed cations show the following sequence: Mg2+ > Na2+ > K+ > Ca2+. A large percent of Cl- was removed (53.3%), whereas SO42- showed the lowest removal (5.1%). The accumulative electroosmosis flow was proportional to the voltage followed by operating time, hydrostatic head, and cathode gap, respectively. © 2016 Elsevier Ltd. All rights reserved.

El Shaer H.M.,Desert Research Center
Small Ruminant Research | Year: 2010

This review paper updates knowledge on the fodder potential of a wide range of halophytes and salt-tolerant forages. These plants can produce relatively high consumable biomass in saline areas where non-halophytic species cannot grow or have low dry matter yields. Therefore, halophytes and some other salt-tolerant plants can provide a drought reserve or a supplementary feed source under arid and semi-arid conditions. On grazing lands, the halophytes can serve as a complementary nutrients source to other conventional feedstuffs, such as Atriplex spp. and cereal straws or hays. In addition to biomass production, wide variations in palatability, chemical composition, nutritive value and animal responses to several halophytes and salt-tolerant forages have been reported in the literature. Some of these species could be valuable sources of minerals and or nitrogen. However, the provision of energy supplements (e.g. barley) is necessary to overcome maintenance and or moderate production requirements of sheep and goats fed on halophytes and or salt-tolerant forages-based diets. Many studies showed that these plants could be used advantageously as alternative feeds to replace totally or partially common feedstuffs, thus to alleviate feeding cost. However, the presence of high contents of ash, plant secondary metabolites and non-protein nitrogen (NPN) should be taken into consideration when formulating diets containing halophytes and or salt-tolerant forages for small ruminants. Although most of feeding studies reported in this review have been carried in the Near East region, mainly in Egypt, results obtained in other regions worldwide support that feeding salt-tolerant plants and halophytes could promote livestock production systems, increase farmers' incomes and improve environmental conditions in the saline areas. © 2010 Elsevier B.V. All rights reserved.

The use of 14C (half-life = 5,730 years) in modeling the evolution of the 36Cl/Cl ratios in groundwater is reported for the first time. The complexity of the Cl–36Cl system due to the occurrence of different Cl and 36Cl sources and the difficulty of the determination of the initial groundwater 36Cl/Cl ratios have raised concerns about the reliability of using 36Cl (half-life = 301 thousand years, a) as a groundwater-dating tool. This work uses groundwater 14C age as a calibrating parameter of the Cl–36Cl/Cl decay-mixing models of three wells from the southwestern Great Artesian Basin (GAB), Australia. It aims to allow for the different sources of Cl and 36Cl in the southwestern GAB aquifer. The results show that the initial Cl concentrations range from 245 to 320 mg/l and stable Cl is added to groundwater along flowpaths at rates ranging from 1.4 to 3.5 mg/l/ka. The 36Cl content of the groundwater is assumed to be completely of atmospheric origin. The samples have different Cl–36Cl/Cl mixing-decay models reflecting recharge under different conditions as well as the heterogeneity of the aquifer. © 2016 Springer-Verlag Berlin Heidelberg

A field experiment was carried out during 2013 and 2014 seasons on 13 years old Manfalouty pomegranate trees grown in sandy soil under drip irrigation system from well at El-Maghara Experimental Station, Desert Research Center, North Sinai Governorate, Egypt. The main objective of this work is to study the effect of four rates of ammonium nitrate fertilizer (600, 900, 1200 and 1500 g/tree) and three concentrations of calcium chloride spray at (0, 1 and 2%) on vegetative growth parameters, yield and fruit quality (especially fruit cracking and sunburn damage) of Manfalouty pomegranate trees. Obtained results showed that ammonium nitrate fertilizer and/or calcium chloride alone or in combination enhanced vegetative growth parameters, yield, fruit quality traits and reducing fruit cracking and sunburn damage through increasing vegetative development and thereby improve protection of the fruits from direct sunlight and the role of Ca in controlling physiological disorders of fruit. © 2016 Elsevier B.V.

Rateb S.A.,Desert Research Center
Small Ruminant Research | Year: 2016

The current investigation aimed to evaluate the rheological and physical properties of camel semen subjected to liquefaction by high-power low frequency ultrasound. Ejaculates (n = 18) were collected during the rutting season from 2 adult male camels, Camelus dromedarius, (9 ejaculates each) using a modified artificial vagina. Immediately after collection, each ejaculate was split into 3 aliquots by a split-sample technique. The first aliquot (raw) was evaluated for rheological, physical and morphological properties, whereas the other 2 aliquots were diluted (1:3) with Tris-lactose egg yolk extender. An aliquot of diluted semen served as control and was evaluated for the aforementioned criteria immediately after dilution (T0) and after an equilibration period of 3 h at 5 °C (T180). Meanwhile, the other diluted specimen was exposed to 4 sets of a 40 kHz ultrasound nominal frequency, 2 min each at 2 min interval, at 37 °C for physical viscosity elimination. Throughout the exposure period, semen rheological properties and sperm physical characteristics were evaluated. Thereafter, sperm kinetics of equilibrated control and ultrasonic-treated semen were objectively assessed by a computer-assisted sperm analysis (CASA) unit. Time of exposure to the ultrasonic waves was negatively correlated (P < 0.01) with each of viscosity score (r = −0.95) and thread length (r = −0.93), whereas it was positively correlated (P < 0.01) with the percent of progressive motility (r = 0.87). Furthermore, ultrasonic-treated semen recorded higher (P < 0.05) motility, viability and sperm dynamics criteria than those of control. These results point to the successful application of ultrasound technology to improve handling, evaluation and processing of camel semen. © 2016 Elsevier B.V.

El-Bahrawy K.A.,Desert Research Center
Journal of Camel Practice and Research | Year: 2010

This study was conducted to investigate the effect of α-amylase on the high viscous nature of dromedary camel semen used for processing of cryopreserved doses. Five different concentrations (0, 2.5, 5, 10, 15 μl/ml) were used as a mucolytic agent for seminal plasma glutinosity liquefaction prior freezing (during 4 hours of equilibration period). The enzyme was added in Tris-Lactose 3% glycerolated extender (TLG) supplemented with 20% fresh egg-yolk. Semen was collected from 3 adult bulls (12 years old); semen ejaculates were assessed immediately for motility. Samples with mass motility higher than 60% and individual forward motility more than 20% were directly splitted on the α-amylase-TLG mix and equilibrated on 5°C for 4 hours before freezing. The results showed a significant (P<0.05) increase in the sperm motility at the high concentrations of amylase treatments 5, 10, 15 μl/ml being 55%, 56.6% and 55% respectively, compared to 40% for both of the control sample (0 μl/ml) and that with added 2.5 μl/ml of amylase. No significant effect was reported due to the treatment on either the detached acrosome or the abnormalities. Computer system for semen assessment (Cell motion analyser CMA) was used to investigate some parameters of the cryopreserved treated semen sperms after thawing. Most movements and velocities parameters, namely; distance along tract (μm), straight distance start finish (μm), distance along average track (μm), VCL(μm/S), VSL (μm/S), VAL (μm/S), linearity%, wobble% and straightness% showed increased values (P < 0.05) at concentration of 15 μl of α-amylase as compared with the control sample or at other α-amylase concentrations. In conclusion, α-amylase at concentrations of 5, 10, 15 μl/ml under slow thawing conditions is a proper mucolytic agent for camel seminal plasma viscosity elimination prior cryopreservation. This enhanced the post-thaw forward motility of camel sperm with no significant detectable effect on both of the acrosomal integrity and the abnormalities.

Ibrahim A.H.,Desert Research Center
Emirates Journal of Food and Agriculture | Year: 2015

The aim of this study was to examine the influence of using exopolysaccharide (EPS) producing starter cultures on physicochemical, rheological and sensory properties of fermented camel milk. Four starter cultures of the strains of non-EPS and EPS-producing were combined and distribution in four treatments portions to made yoghurt from camel's milk. Results showed that the maximum acetaldehyde and diacetyl contents were found in control treatment during 7 days storage period. The EPS concentration was detected between 41.3 to 269.3 mg/kg in the yoghurt made with non-EPS and EPS-producing starter cultures. The highest EPS concentration was observed in treatment C (1.5% EPS-producing Streptococcus thermophilus plus 1.5% non EPS-producing Lb. delbrueckii ssp. bulgaricus) during 14 days storage period, then reduced at the end of the storage period. Yoghurt made with any EPS-producing strains had significantly (P<0.05) lower firmness, syneresis and higher viscosity values than control yoghurt. Overall acceptability scores of the sensory evaluation revealed that the yoghurt made with EPS-producing starter cultures in treatment C was the most accepted, while the control treatment was the least. According to the results, exopolysaccharide enhance viscosity, texture and mouthfeel and to avoid syneresis in yoghurt. The results of this study suggest that the use of EPS-producing cultures could provide better textures for camel milk yoghurt than those imparted by additives.

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