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排序方式: 共有133条查询结果,搜索用时 15 毫秒
21.
ABSTRACT Organic matter levels combined with drought periods during the growing season have adverse impacts on rain-fed potato production in coarse textured soils of eastern Canada. Using pulp fiber residues (PFR) may build up soil organic matter, improve crops yield and nutrient uptake, and reduce the need for supplemental irrigation in this region. A box experiment with 3 rates of PFR [0, 45, and 90 Mg ha? 1 dry mater carbon (C) basis] with or without supplementary drip irrigation was established in a sandy loam soil in New Brunswick, Canada. Red clover, barley, and potato were cultivated as three crops of the rotation in 1999, 2000, and 2001, respectively. The PFR only applied before red clover in fall 1998. Selected soil chemical and physical properties were measured before planting and after harvest. Crops yield and nitrogen (N), phosphorus (P), and potassium (K) accumulation were determined at harvest. Soil organic-C content, bulk density and water holding capacity were improved by PFR application. Red clover and barley biomass production were significantly increased by PFR application. This effect was promoted by supplemental irrigation. Potato tuber yield was not affected by PFR and it was higher in rain-fed compared to supplementary irrigated system. Although, there was some initial evidence of N immobilization but generally PFR application increased N, P, and K bioavailability. This research has demonstrated that PFR can successfully be used as soil amendment in coarse textured soils without any adverse effect. 相似文献
22.
An effective method for the synthesis of 7,8-epoxy-1,3,11-cembratriene- 15R(α),16-diol and its in vitro Epstein-Barr Virus Early Antigen (EBV-EA) Activation Chemopreventive Assay are reported. This semisynthetic product is a new cembranoid with a potent tumor inhibitory activity that is expected to be a lead compound for a new class of chemopreventive agents of marine origin. 相似文献
23.
Irrigation rate and plant density effects on yield and water use efficiency of drip-irrigated corn 总被引:3,自引:0,他引:3
Salah E. El-Hendawy Essam A. Abd El-Lattief Mohamed S. Ahmed Urs Schmidhalter 《Agricultural Water Management》2008,95(7):836-844
The efficient use of water by modern irrigation systems is becoming increasingly important in arid and semi-arid regions with limited water resources. This study was conducted for 2 years (2005 and 2006) to establish optimal irrigation rates and plant population densities for corn (Zea mays L.) in sandy soils using drip irrigation system. The study aimed at achieving high yield and efficient irrigation water use (IWUE) simultaneously. A field experiment was conducted using a randomized complete block split plot design with three drip irrigation rates (I1: 1.00, I2: 0.80, and I3: 0.60 of the estimated evapotranspiration), and three plant population densities (D1: 48,000, D2: 71,000 and D3: 95,000 plants ha−1) as the main plot and split plot, respectively. Irrigation water applied at I1, I2 and I3 were 5955, 4762 and 3572 m3 ha−1, respectively. A 3-day irrigation interval and three-way cross 310 hybrid corn were used. Results indicated that corn yield, yield components, and IWUE increased with increasing irrigation rates and decreasing plant population densities. Significant interaction effects between irrigation rate and plant population density were detected in both seasons for yield, selected yield components, and IWUE. The highest grain yield, yield components, and IWUE were found for I1D1, I1D2, or I2D1, while the lowest were found for I3D2 or I3D3. Thus, a high irrigation rate with low or medium plant population densities or a medium irrigation rate with a low plant population density are recommended for drip-irrigated corn in sandy soil. Crop production functions with respect to irrigation rates, determined for grain yield and different yield components, enable the results from this study to be extrapolated to similar agro-climatic conditions. 相似文献
24.
The concentration of lead has been determined in samples of whole blood from Osimi and Rahmani sheep grazing near main highways in three areas of the Nile delta region of Egypt. Between 117 and 200 blood samples were collected from each area. The mean values for the blood lead content were 0.062, 0.067 and 0.083 micrograms/ml, and were low in all the locations. The value of 0.083 micrograms/ml obtained for the samples taken from the partly industralised Enshass region was significantly higher than the mean values from the other sites. 相似文献
25.
Salah A. A. Robertson I.D. Mohamed A. SH. 《Tropical animal health and production》2019,51(8):2371-2377
Tropical Animal Health and Production - The prevalence and distribution of Trypanosoma evansi (T. evansi) infection on camels in Somaliland were studied using the card agglutination test (CATT/T.... 相似文献
26.
L. Bigarré M. Chazly M. Salah M. Ibrahim M. Padidam M. Nicole M. Peterschmitt C. Fauquet J.C. Thouvenel 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(7):701-711
A viral isolate from Egypt associated with symptoms of enations and leaf curling on hollyhock (Althea rosea) was characterized at the cytopathological and molecular levels. Microscopic observations showed that enations resulted from a reorganization of the vascular tissues, including activation of a cambial activity in the phloem, the development of a palisade parenchyma in place of a spongy one and the differentiation of minor vascular tissues. From this isolate, the full-length DNA-A of a begomovirus (family Geminiviridae) was cloned and sequenced. This genome exhibited a genetic organization similar to that of other old-world begomoviruses like Tomato yellow leaf curl virus from Israel and Ageratum yellow vein virus from Singapore. However, its sequence was significantly distinct (similarity < 69%) from any other geminivirus. This begomovirus was thus considered as representative of a new viral species named Althea rosea
enation virus (AREV). AREV was agroinfectious on Nicotiana benthamiana, on which it induced a severe leaf-curling and vein distortion, but could not re-establish infection on A. rosea. To determine if AREV was also associated with a similar disease affecting okra in Upper-Egypt, the partial sequence of the coat protein gene of an isolate was determined. It exhibited 90% nt identity with the hollyhock isolate (97% amino acid), suggesting a genetic heterogeneity in the begomovirus population associated with the enation diseases. 相似文献
27.
Ayman S. Salah Omar A. Ahmed‐Farid Mahmoud S. El‐Tarabany 《Journal of animal physiology and animal nutrition》2019,103(1):41-52
The objective of the current research was to explore the possible impacts of dietary supplementation with synbiotic and/or organic acids (OA) on the performance traits, carcass yields and muscle amino acid and fatty acid (FA) profiles of broilers. Randomly, a total of 160 day‐old chicks (Ross 308) were assigned into four equal groups (40 birds each), with each group subdivided into eight replicates (five birds/pen). The control group (CON) fed the basal diet with no supplements, while diets of the treated groups were supplemented with OA (Sodium butyrate 40%; 1 g/kg), synbiotic (comprised Bacillus subtilis, Saccharomyces cerivisiae, Streptococcus faecium, Mannan‐Oligosaccharides and β‐Glucan; 1 g/kg) and equal mix of OA and synbiotic (2 g/kg). Broilers fed the diets supplemented with synbiotic or synbiotic plus OA produced a significantly higher feed utilization efficiency (p = 0.021) and carcass yields (p = 0.038) than the CON and OA‐supplemented groups. The group fed the diet supplemented with the synbiotic showed lowered serum cholesterol (p = 0.049), triglycerides (p = 0.001) and very low density lipoprotein (p = 0.032) when compared with the CON group. Regarding the polyunsaturated FA (PUFA) of breast muscles, synbiotic‐supplemented birds had significantly lower n‐6:n‐3 ratio (p = 0.047), however, a greater hypocholesterolaemic to hypercholesterolaemic FA (H/H) ratio was reported when compared with the CON group (p = 0.002). Among the essential amino acids, the contents of leucine and methionine in the breast (p = 0.032 and 0.007 respectively) and thigh (p = 0.023 and 0.003 respectively) muscles were greater in the synbiotic‐supplemented birds compared with the CON group. In conclusion, the synbiotic‐supplemented diet improved the PUFA:SFA, n‐6:n‐3 and H/H ratios by altering the FA composition of broiler muscles, which are important with regards to human health. 相似文献
28.
何闪 《国外畜牧学(猪与禽)》2013,33(4):36-37
在家禽生产中,家禽的生产性能通常和一些常规要素,如健康状况和营养相关。然而,环境噪音的影响也不容小觑。家禽不喜欢嘈杂的环境,且往往会表现出较差的生产性能。在养禽场中,与动力设备相关的噪音强度最好用听力计检测并以分贝(dB)为单位进行表示。表1所示为养禽场内家禽生产环境中允许的噪音水平及相应的可承受接触时间。如果家禽暴露在更高水平的噪音环境中,或暴露的时间长于推荐的时间,那 相似文献
29.
Martinez MN Kawalek JC Howard KD Ward JL Marroum P Marnane W Bensley D Pelsor FR Hoag S Tatavarti AS Xie L Fahmy R 《Journal of veterinary pharmacology and therapeutics》2006,29(6):459-467
The bolus (or oblet) is a dosage form that can be used for the oral administration of pharmaceutical compounds to ruminating species. Unlike traditional tablets, oral boluses may contain quantities of drug on the order of grams rather than milligrams. Due to its size, it is only recently that USP-like in vitro dissolution methods have been developed for this dosage form. However, whether or not these dissolution tests can predict product in vivo performance has yet to be determined. The importance of this issue is apparent when the U.S. Food and Drug Administration Center for Veterinary Medicine is faced with the decision of whether to require additional in vivo bioequivalence study data to support the approval of changes in product chemistry or manufacturing method. The current study was undertaken to determine whether an in vivo/in vitro correlation can be established for bovine sulfamethazine oral boluses and to acquire insight into the magnitude of changes in in vitro product performance that can occur before corresponding changes are seen in in vivo blood level profiles. Based upon the results of this investigation, it is concluded that marked changes in in vitro sulfamethazine bolus performance can be tolerated before resulting in altered in vivo blood level profiles. However, the data also suggest that rumenal absorption may occur for some compounds. Therefore the degree to which variation in product in vitro dissolution profiles can be tolerated may be compound specific. 相似文献
30.
Chérif N Thiéry R Castric J Biacchesi S Brémont M Thabti F Limem L Hammami S 《Veterinary research communications》2009,33(4):345-353
Viruses belonging to the Nodaviridae family cause disease worldwide among a large number of species of marine fish, and have
been described in all continents. In the present study, a total of 69 farmed Tunisian sea bass (Dicentrarchus labrax) and
24 sea bream (Sparus aurata) samples were tested monthly for the detection of betanodavirus. The virus was identified in both
species using indirect immunofluorescence assays (IFAT) and RT-PCR. In addition sequence analysis of part of the coat protein
gene indicated that both species were infected by highly related, but distinct, strains belonging to the RGNNV genotype. The
sequence of the coat protein gene of several strains was identical but up to 9 different sequences were detected in a single
farm. In addition, viral sequences obtained from fish that were held at lower temperature (<20°C) were distinct from the rest
of the sequences. 相似文献