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121.
122.
Ahmed M. Soliman Ehab A. Abu-Basha Salah A. H. Youssef Aziza M. Amer Patricia A. Murphy Catherine C. Hauck Ronette Gehring Walter H. Hsu 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(4):395-403
A study of amoxicillin pharmacokinetics was conducted in healthy goats and goats with chronic lead intoxication. The intoxicated goats had increased serum concentrations of liver enzymes (alanine aminotransferase and γ-glutamyl transferase), blood urea nitrogen, and reactivated δ-aminolevulinic acid dehydratase compared to the controls. Following intravenous amoxicillin (10 mg/kg bw) in control and lead-intoxicated goats, elimination half-lives were 4.14 and 1.26 h, respectively. The volumes of distribution based on the terminal phase were 1.19 and 0.38 L/kg, respectively, and those at steady-state were 0.54 and 0.18 L/kg, respectively. After intramuscular (IM) amoxicillin (10 mg/kg bw) in lead-intoxicated goats and control animals, the absorption, distribution, and elimination of the drug were more rapid in lead-intoxicated goats than the controls. Peak serum concentrations of 21.89 and 12.19 µg/mL were achieved at 1 h and 2 h, respectively, in lead-intoxicated and control goats. Amoxicillin bioavailability in the lead-intoxicated goats decreased 20% compared to the controls. After amoxicillin, more of the drug was excreted in the urine from lead-intoxicated goats than the controls. Our results suggested that lead intoxication in goats increases the rate of amoxicillin absorption after IM administration and distribution and elimination. Thus, lead intoxication may impair the therapeutic effectiveness of amoxicillin. 相似文献
123.
Genetic analysis of Trichinella populations by 'cold' single-strand conformation polymorphism analysis 总被引:2,自引:0,他引:2
A non-isotopic single-strand conformation polymorphism ('cold' SSCP) technique has been assessed for the analysis of sequence variability in the expansion segment 5 (ES5) of domain IV and the D3 domain of nuclear ribosomal DNA within and/or among isolates and individual muscle (first-stage) larvae representing all currently recognized species/genotypes of Trichinella. Data are consistent with the ability of cold SSCP to identify intra-specific as well as inter-specific variability among Trichinella genotypes. The cold SSCP approach should be applicable to a range of other genetic markers for comparative studies of Trichinella populations globally. 相似文献
124.
H. H. Tantawi A. M. El Batrawi M. A. Bastami Y. I. Youssef M. M. Fawzia 《Veterinary research communications》1983,6(1):281-287
Serious outbreaks of haemorrhagic tracheitis in poultry induced by infectious laryngo-tracheitis virus (ILTV) have been recorded in Egypt for the first time. The disease occurred in different localities during late 1982 and early 1983. The associated drop in egg production ranged between 5% and 35% and there was a mortality rate which ranged from 0.05% to 19.8%. The causal virus was isolated on the chorioallantoic membrane (CAM) of developing chicken embryos where it induced large yellowish-white pock lesions, 3–4 mm in diameter, by the fifth or sixth day post-inoculation. It was non-lethal to the inoculated embryos. It grew also with cytopathic effect (CPE) on the CER cell line. The CPE was characterized by syncytial formation and intranuclear inclusions. Chickens experimentally inoculated with the virus developed respiratory signs and 14 of 20 birds died with subsequent virus re-isolation. The isolated virus was unable to agglutinate chicken red cells and it was precipitated and partially neutralized by reference serum to ILTV. Viral antigen was detected by the indirect fluorescent antibody technique in tracheal smears obtained from naturally and experimentally infected birds. This is the first report of the isolation of ILTV in Egypt. 相似文献
125.
M Atef A Ramadan N A Afifi S A Youssef 《DTW. Deutsche tier?rztliche Wochenschrift》1990,97(8):324-327
Cefotaxime was once administered in goats via intravenous, intramuscular and subcutaneous routes for determination of blood and urine concentration, kinetic behaviour and bioavailability. Following a single intravenous injection, the blood concentration-time curve indicated two compartments open model, with an elimination half-life value (t1/2 beta) of 22.38 +/- 0.41 minutes. Both intramuscular and subcutaneous routes showed lower values i.e. 38.64 and 69.58 minutes. The lower apparent volume of distribution of cefotaxime in goats than one liter/kg elucidated lower distribution in tissues than in blood. After intramuscular and subcutaneous injections peak plasma cefotaxime concentrations were 77.8 +/- 1.7 and 44.0 +/- 0.8 micrograms/ml at 29.6 and 40.4 minutes, respectively. The average bioavailability of cefotaxime given by intramuscular and subcutaneous injection was 1.08 and 1.25, respectively. The cefotaxime concentration remained in urine 24 hours longer after subcutaneous injection than after intramuscular administration. 相似文献
126.
Valerio Cristofori Youssef Rouphael Emilio Mendoza-de Gyves Cristina Bignami 《Scientia Horticulturae》2007
Simple, accurate and non-destructive models determining leaf area of plants are important for many experimental comparisons. Determining the individual leaf area (LA) of hazelnut (Corylus avellana L.) involves measurements of leaf parameters, such as length (L) and width (W), or some combinations of these parameters. Two-year investigation was carried out during 2005 (on 20 genotypes) and 2006 (on one cultivar) under open field conditions, respectively, to test whether a model could be developed to estimate leaf area across genotypes and environments. Regression analyses of LA versus L and W revealed several models that could be used for estimating the area of individual hazelnut leaves. A linear model having LW as the independent variable (LA = 2.59 + 0.74LW) provided the most accurate estimate (R2 = 0.982, MSE = 29) of hazelnut LA. Validation of the model having LW of leaves measured in the 2006 experiment coming from other genotype grown under different environmental conditions showed that the correlation between calculated and measured areas was very high. 相似文献
127.
Clercx C Peeters D German AJ Khelil Y McEntee K Vanderplasschen A Schynts F Hansen P Detilleux J Day MJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(3):229-237
Immunologic variables in dogs with eosinophilic bronchopneumopathy (EBP) have not been extensively evaluated. The aim of this study was to determine immunoglobulin (Ig) concentrations and to perform phenotypic subtyping of lymphocytes in the bronchoalveolar lavage fluid (BALF) and peripheral blood (PB) of 12 dogs with EBP at the time of diagnosis (TD) and to compare these data with those obtained in healthy dogs, as well as in EBP dogs after antibiotic therapy (TAB) and during corticosteroid treatment (TM). Matched samples of serum and BALF were used to determine Ig concentrations (IgG, IgM, and IgA) by capture enzyme-linked immunosorbent assay (ELISA), from which a secretory index (SI) was calculated. Lymphocyte subpopulations were studied in the BALF and PB by flow cytometry. Log values of BALF IgM and IgA were significantly higher (0.64+/-0.05 and 1.06+/-0.13, respectively) in EBP dogs at TD than in controls and then tended to decrease at TM (0.55+/-0.03 and 1.02+/-0.17, respectively). A calculated SI for IgA was not significantly increased. In the BALF of dogs with EBg the CD4: CD8 was significantly (P < .05) higher (22.6+/-30.3) than in controls (3.2+/-1.9), due to significantly higher CD4+ T cells and lower CD8+ T cells. At TM, the BALF T-cell percentages returned to normal (2.4+/-0.6). We propose that the influx of eosinophils into the airway of dogs with EBP is at least in part mediated by cytokines derived from CD4+ T cells. Further studies of canine cytokines and chemokines will help determine whether canine EBP involves type I hypersensitivity mechanisms regulated by Th2 lymphocytes. 相似文献
128.
Giancarlo Fascella Michele M. Mammano Francesca D’Angiolillo Youssef Rouphael 《The Journal of Horticultural Science and Biotechnology》2018,93(5):519-528
A greenhouse experiment was conducted to assess the performance of biochar obtained from pyrolysis of conifer wood as a substrate component for growing potted Rosa rugosa plants. Rose plants were grown with different mixtures of sphagnum peat and biochar (100% peat, 75% peat–25% biochar, 50% peat–50% biochar, 25% peat–75% biochar; v:v). Increasing the biochar content from 25% to 75% increased the air content, bulk density, electrical conductivity, and K and Na concentration in the substrates. The addition of 25% biochar to the substrate showed promising potential for R. rugosa when compared with 100% peat given the similar growth performance, water-use efficiency, and ornamental quality (number of flowers and leaf colour). The Ca and Na concentrations in leaves and roots as well as the Mg content in roots increased as the biochar percentage in the substrate increased, whereas an opposite trend was observed for P and K concentrations. The best performance and ornamental quality of R. rugosa grown with 100% peat and 75% peat–25% biochar compared with 50 and 75% biochar treatments were attributed to a higher degree of photosynthesis, Soil Plant Analysis Development index, and pigment content. Overall, adding 25% of conifer wood biochar as a substrate component could be applied for economic purposes without detrimental effects on the yield and quality of potted roses. 相似文献
129.
Zonal geranium (Pelargonium × hortorum ‘Real Mintaka’) were grown in closed soilless systems to evaluate the effects of irrigation system (drip and subirrigation) and nutrient solution concentration (half and full) under various conditions of radiation and temperature (winter and summer) in terms of substrate electrical conductivity (ECs), growth, quality, crop evapotranspiration (ETc) and growth index water use efficiency (WUEGI) and nutrient uptake. At he end of the cultural cycle the highest ECs in the upper and lower layers were recorded in the spring season on plants grown in subirrigation using a full nutrient solution concentration. The highest shoot biomass, leaf area, plant growth index, and quality index were recorded in the winter season on plants grown in both drip-irrigation and subirrigation using half and full nutrient solution concentration, whereas the lowest value was observed in the spring season on plants grown with subirrigation using the full nutrient solution concentration. The highest maximum air temperature recorded during the first 20 days after transplanting in the spring growing season was presumably responsible for the reduction in shoot biomass production, growth and quality index, and in time of geranium flowering compared to the plants grown in the winter season. The ETc was 44% higher in spring than in winter season treatment, while the effect of the irrigation system was less pronounced with an increase in 11% in the subirrigation treatment compared with the drip-irrigation system. WUEGI was not stable and showed a seasonal variability. Solar radiaton (Rs), air temperature (Ta) and vapour pressure deficit (VPD) were greatly higher in the spring season, which influenced WUEGI negatively. The WUEGI improved especially when Rs, Ta and VPD were below 12 MJ m2, 20 °C and 0.6 kPa, respectively. The highest N, and Mg uptake were recorded in the winter season, especially on plants grown with subirrigation at 2 dS m−1. The highest P, K, and Ca uptake values were measured during winter season using subirrigation system, and on plants grown under full strength nutrient solution. The variation of the nitrate concentration and EC in the nutrient solution during the spring growing cycle was less pronounced in the subirrigation than with a drip-irrigation system which represents an important aspect for the simplification of the closed loop management of the nutrient solution. 相似文献
130.
Effect of feeding Acacia nilotica pods to sheep on nutrient digestibility,nitrogen balance,ruminal protozoa and rumen enzymes activity
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M. A. M. Abdullah M. M. Farghaly I. M. I. Youssef 《Journal of animal physiology and animal nutrition》2018,102(3):662-669
This study was conducted to evaluate the effect of supplying two levels of Acacia nilotica (A. nilotica) pods to rations of sheep on nutrient digestibility, nitrogen balance and rumen liquor parameters (pH, total protozoa count, protein concentration and enzymes activity). Twelve mature rams (50 ± 1.25 kg B.W.) were distributed into three groups, each with four rams. Animals in group one were considered as a control which fed a basal diet, consisting of concentrate mixture and Egyptian clover. The second group and the third one received the same basal diet with supplying the concentrate mixture by 1.5% and 3.0% of A. nilotica pods meal respectively. The experiment lasted for 3 weeks. It was found that supplementation of A. nilotica pods to the concentrate mixture at a rate of 1.5% and 3.0% significantly improved the total feed intake compared to the control. The digestibility of dry matter and crude fibre was significantly reduced with A. nilotica supplements, whereas the digestibility of crude protein was significantly improved. All of nitrogen intake and N‐retained were significantly increased in rams fed on concentrates with 1.5% and 3.0% A. nilotica pods when compared to the control. The pH of ruminal fluid was not affected by the dietary treatments. Nevertheless, the total rumen protozoa count was significantly decreased in A. nilotica pods supplemented groups. Also, the rumen protein concentration and the ruminal enzymes activity, especially α‐amylase, cellulase and protease, were lower in A. nilotica pods supplemented treatments. In conclusions, inclusion of low levels of A. nilotica pods (1.5% and 3.0%) in the concentrates can be used as a natural protein protectant in ruminants by forming tannin protein complexes in the rumen to maximize the amino acids available in the lower digestive tract. Also, these levels can increase the protein digestibility as well as the N‐retained in the body . 相似文献