Molecular screening and risk factors of enterotoxigenic Escherichia coli and Salmonella spp. in diarrheic neonatal calves in Egypt     

Emad E. Younis  Ashraf M. Ahmed  Sabry A. El-Khodery  Salama A. Osman  Yasser F.I. El-Naker 《Research in veterinary science》2009,87(3):373-379

The aim of the present study was to carry out molecular epidemiological investigation on enterotoxigenic Escherichia coli (ETEC) K99 and Salmonella spp. in diarrheic neonatal calves. Fecal samples were obtained from 220 diarrheic calves at 9 farms related to four governorates in central and northern Egypt. E. coli and Salmonella spp. isolates were examined for E. coli K99 and Salmonella spp. using PCR. ETEC K99 was recovered from 20 (10.36 %) out of 193 isolates, whereas Salmonella spp. was recovered from nine calves (4.09%).Multivariable logistic regression was used to evaluate the risk factors associated with both infections. ETEC K99 was significantly affected by age (P < 0.01; OR: 1.812; CI 95%: 0.566–1.769), colostrum feeding practice (P < 0.01; OR: 5.525; CI 95%: 2.025–15.076), rotavirus infection (P < 0.001; OR: 2.220; CI 95%: 0.273–1.251), vaccination of pregnant dams with combined vaccine against rotavirus, coronavirus and E. coli (K99) (P < 0.001; OR: 4.753; CI 95%: 2.124–10.641), and vitamin E and selenium administration to the pregnant dam (P < 0.01; OR: 3.933; CI 95%: 0.703–1.248).Infection with Salmonella spp. was found to be significantly affected by the animal age (P < 0.05; OR: 0.376; CI 95%: 0.511–1.369), Hygiene (P < 0.05; OR: 0.628; CI 95%: 1.729–5.612), and region (P < 0. 01; OR: 0.970; CI 95%: 0.841–1.624).The results of the present study indicate the importance of PCR as rapid, effective and reliable tool for screening of ETEC and Salmonella spp. when confronted with cases of undifferentiated calf diarrhea. Moreover, identification of the risk factors associated with the spreading of bacteria causing diarrhea may be helpful for construction of suitable methods for prevention and control.  相似文献   

优质高品质陆地棉品种(系)数量性状因子分析及稳定性评价     

王莉  阿同古丽·吾斯曼  库尔班·牙生  李卫平  曲延英 《新疆农业科学》2013,50(4):589

[目的]为指导优质陆地棉常规育种提供科学参考.[方法]对63个高品质陆地棉资源(即纤维长度30 mm、以上比强度31 cN/tex以上、马克隆值3.7 ～4.2)的14个数量性状进行因子分析并聚类,对其纤维品质进行稳定性评价.[结果]前5个公因子的累积贡献率达到90.0;,分别代表籽指、铃重、比强度、铃数、纤维整齐度、纤维细度等陆地棉的主要特征,并根据这63个品种(系)的前5个公因子的得分值,采用离差平方和法将其聚为9类,其中大铃优质、早熟性、高衣分上表现好的分别是Ⅸ、Ⅷ、Ⅵ类.[结论]通过因子分析聚类以及稳定性评价后最终预测出12个较理想的亲本,即贝尔斯诺、Acala1517-77、Aca1a1 517-70、巴州5628、SI2、霍皮卡尔、MO-78-344、117169-6、新陆中9号、巴州6501、长绒67-12和新培育品系.  相似文献   

Antioxidant Activities of Citrus Albedo and Flavedo Fragments Against Fish Lipid Oxidation     

Pinar Yerlikaya  Nalan Gokoglu  Osman Kadir Topuz  Bahar Gumus  Hanife Aydan Yatmaz 《Journal Of Aquatic Food Product Technology》2013,22(8):1339-1347

ABSTRACT

This research aimed to inhibit the oxidation of fish lipid by adding the ethanol extracts of albedo and flavedo fragments of grapefruit, sour orange, and bergamot. The samples were stored at 25°C, and analyses were performed on weekly intervals. The albedo fragments of sour orange extract had the highest antioxidant activity (0.342 ± 0.002 µM Trolox) and total phenolic content (5.29 ± 0.00 g GAE/100 g dry matter). Lipid oxidation increased rapidly in control samples compared to the extract treatments. The lowest scores for thiobarbituric acid reactive substances (TBARS), para-anisidine value, peroxide value, and UV absorbance values were determined in sour orange albedo extracts as 5.21 mg MDA/kg, 17.81 and 4.78 meq O₂/kg, 2.24, and 0.403, respectively, at the end of the storage. More successful results were obtained with the peels of grapefruit and bergamot in supressing the lipid oxidation. Bergamot extract was the most preferred citrus in terms of sensory analyses.  相似文献   

Effects of heat treatment on some properties of MDF (medium-density fiberboard)     

Saim Ates  Hasimet R. Kara  Cag˘ri Olgun  Osman E. Ozkan 《Wood material science & engineering》2017,12(3):158-164

This work investigated some mechanical, physical and free formaldehyde emission properties of heat-treated MDF. For this purpose, MDF panels were subjected to varying heat treatment temperatures (155°C, 165°C and 175°C), durations (2.5?h., 3.5?h. and 4.5?h.) and waiting times after hot pressing (30?min., 120?min. and 600?min). Thickness swelling (TS), water absorption (WA), free formaldehyde emission (FFE), bending strength (BS), modulus of elasticity (MOE), tensile strength perpendicular to fibers (TSPF) for treated and untreated samples were tested and evaluated statistically. Consequently, after the heat treatment values of tensile strength, bending strength and modulus of elasticity were almost negatively affected relatively, but the thickness swelling and water absorption and quantities of free formaldehyde were improved positively of MDF samples.  相似文献   

Apoptosis in the Myocardium of the Adult Dromedary Camel: Ultrastructural Characterization     

A.-H. K. Osman  S. Sato  T. Caceci  D. C. Pfeiffer 《Anatomia, histologia, embryologia》2010,39(1):34-41

Apoptosis is a highly regulated mode of cell death that occurs in the absence of inflammation. Light microscopic (LM) examination of the myocardium of apparently healthy camel did not reveal evidence of apoptosis in any samples; however, evidence of apoptosis was apparent by transmission electron microscopy (TEM). The most common apoptotic features observed by TEM included (1) an intact sarcolemma with some bleb formation; (2) nuclear chromatin condensation and margination with nucleolar disruption; (3) mitochondrial swelling and disorganization, accompanied by degeneration or hypercondensation of cristae; and (4) an intercalated disc region with a higher-than-normal mitochondrion/myofibril ratio, or surrounded from both sides by asymmetrically contracted sarcomeres. Apoptotic alterations were also noted among the endothelial cells lining the microvasculature of the myocardium. These alterations included (1) marked nuclear chromatin condensation and margination; (2) villous blebs on the adluminal plasmalemma, which projected into the lumen; (3) cytoplasmic vacuolation; (4) presence of intraluminal membrane-bounded vesicles; and (5) occasional pericapillary edema and accumulations of cellular debris. The results of this study indicate that myocardial apoptosis can occur in apparently healthy camels, in the absence of a clear-cut etiology.  相似文献   

陆地棉机采性状对皮棉产量的遗传贡献分析   总被引：5，自引：0，他引：5  

努斯热提·吾斯曼  喻树迅  范术丽  梅拥军  原日红 《棉花学报》2012,24(1):10-17

 采用加性-显性-加加上位性及其与环境互作的遗传模型（ADAA模型）,对8个陆地棉亲本（其中有6个机采棉品种）及其F₁和F₂的28个组合5个机采性状和单株皮棉产量的新疆阿拉尔和石河子2试点资料,进行了贡献分析。结果表明,5个机采性状对皮棉产量表型值的贡献变化范围为－20%～－14%;在显性贡献中,第一果枝高度对皮棉产量的贡献率最大（CR_D=10%）,其次是节间长度的贡献（CR_D=8%）,而霜前花率对皮棉产量有较大的抑制作用（CR_D=－25%）;霜前花率对皮棉产量的加加上位贡献率最大（CR_AA=86%）,其次是第一果枝节位（CR_AA=24%）。霜前花率在特殊的环境中对皮棉产量表现为很大的显性正向贡献（CR_DE=78%）和加加上位效应抑制作用。不同亲本5个机采性状对其皮棉产量的显性和加加上位效应贡献不同。5个机采性状对不同组合皮棉产量显性效应的贡献较小,霜前花率对皮棉产量的显性效应的贡献在2个地点的表现往往和单株皮棉产量在不同地点表现显性效应的性质（正或负）相一致,并且在5个机采性状中对皮棉产量的显性贡献是最大的。加加上位效应在皮棉产量的遗传中起着很重要的作用,而在8个亲本及其后代各组合的5个机采性状中,霜前花率可作为选择皮棉产量加加上位效应的主选性状。在不同的环境中,皮棉产量加加上位效应的主选机采性状随组合有所不同。  相似文献   

Circulating oxidative stress status in dromedary camels infested with sarcoptic mange   总被引：2，自引：0，他引：2  

Saleh MA  Mahran OM  Bassam Al-Salahy M 《Veterinary research communications》2011,35(1):35-45

Oxidative stress is an imbalance between radical-generating and radical-scavenging activity, resulting in oxidation products and tissue damage. This study was aimed to evaluate the status of oxidative stress indices in blood of camels naturally infested with S. scabiei. Forty-seven male camels (Camelus dromedaries) were divided according to the extent of the infested area with Sarcoptes scabiei into four groups, mild (MID, n = 12), moderate (MOD, n = 10), severely infested (SEV, n = 10) and healthy control group (n = 15). Blood was used for determination of red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV), serum nitric oxide (NO^•, a free radical), ascorbate and albumin concentrations, and erythrocytic values of malondialdehyde (MDA, a marker of lipid peroxidation), protein carbonyls (PC, an indicator of protein oxidation), glutathione (GSH) superoxide dismutase (SOD) and catalase (CAT). Decreased levels (P < 0.05) of RBC, Hb, PCV, albumin and ascorbate were noticed in MOD and SEV compared to controls with the lowest values (P < 0.05) in SEV except for ascorbate, where MOD did not differ from SEV. Compared to controls, NO^• gradually increased (P < 0.05) in MID followed by MOD and SEV, whereas MDA and PC were higher (P < 0.05) in MOD and SEV. PC was higher (P < 0.05) in MOD than SEV. In addition, the antioxidants GSH, SOD and CAT were higher (P < 0.05) in MID and lower (P < 0.05) in MOD and SEV compared to controls. GSH was lower (P < 0.05) in SEV compared to MOD. Besides, Hb was negatively correlated with NO^• (r = −0.68, P < 0.001), MDA (r = −0.53, P < 0.001) and PC (r = −0.73, P < 0.001). In conclusion, dromedary sarcoptosis is accompanied by a state of oxidative stress process, which increased by increasing the area of infestation, and may contribute to the pathogenesis of the disease.  相似文献   

Effect of magnesium fertilization on yield and leaf composition of tomato plants     

Osman M. Elamin  Gerald E. Wilcox 《Journal of plant nutrition》2013,36(11):999-1022

Tomato plants were grown for 2 years at 4 different rates of Mg fertilization on a Princeton loamy sand at pH 4.8 with 29 kg exchangeable Mg/ha. Calcareous limestone was used to provide a pH treatment in the second year. Magnesium deficiency symptoms were observed on plants grown on plots having ≤ 38 kg/ha NH₄OAC‐extractable Mg. Application of 56 kg Mg/ha corrected Mg deficiency and produced a significant increase in yield. Application of calcitic limestone also produced significant yield increases, but did not affect the development of Mg deficiency symptoms. Tomato yield was increased 27.9% by Mg application and 17.7% by lime application. Highest tomato yield was obtained with application of 112 kg Mg/ha. Symptoms of Mg deficiency were observed when the Mg concentration in recently mature leaf tissue was in the 0.30 to 0.32% range. Magnesium concentration in leaf tissue increased linearly with increasing Mg rate. Leaf Mg concentration at various growth stages of the tomato plant was variable depending on Mg treatment. Magnesium fertilization rate bad little effect on Ca or K leaf concentrations. Application of Calcltic limestone increased leaf tissue Ca and reduced leaf tissue Mg and Mn concentrations.  相似文献   

Phenotypic diversity and evolution of farmer varieties of bread wheat on organic farms in Europe     

J. C. Dawson  E. Serpolay  S. Giuliano  N. Schermann  N. Galic  J.-F. Berthellot  V. Chesneau  H. Ferté  F. Mercier  A. Osman  S. Pino  I. Goldringer 《Genetic Resources and Crop Evolution》2013,60(1):145-163

The contribution of farmers to the creation and maintenance of genetic diversity is beginning to receive more recognition in developed countries. Although the use of landraces and historic varieties has largely disappeared in countries with industrialized agricultural systems and formal seed markets, certain varieties with particular cultural significance have been continuously cultivated by farmers and other varieties have been preserved ex situ in genebanks. Recently, associations of organic farmers have become involved in the conservation and use of landraces and historic varieties (called farmer varieties in this article) because these varieties possess agronomic and quality traits that they have not found in modern varieties. In this study, eight farmer varieties of bread wheat from Europe selected by participating farmers were evaluated in on-farm trials during 3 years of cultivation. Each variety was grown on each farm, and phenotypic changes in each variety were measured the third year in a replicated split-plot trial on each farm comparing the version of each variety the farmer had multiplied to a sample of each variety from the region of origin. All varieties, including the two modern pureline varieties used as checks, showed statistically significant phenotypic changes over 3 years of multiplication. However, the magnitude of these changes was moderate and did not call into question varietal identity or distinctness. In addition, some traits of putative agronomic and adaptive importance, such as grain weight per spike and thousand kernel weight, did not respond positively to natural selection (environmental conditions and management practices) which suggests the necessity of farmer selection to maintain and improve varietal performance.  相似文献   

Cultured meat from muscle stem cells:A review of challenges and prospects     

Isam T Kadim  Osman Mahgoub  Senan Baqir  Bernard Faye  Roger Purchas 《中国农业科学(英文版)》2015,(2):222-233

Growing muscle tissue in culture from animal stem cells to produce meat theoretically eliminates the need to sacrifice animals. So-called "cultured" or "synthetic" or "in vitro" meat could in theory be constructed with different characteristics and be produced faster and more efficiently than traditional meat. The technique to generate cultured muscle tissues from stem cells was described long ago, but has not yet been developed for the commercial production of cultured meat products. The technology is at an early stage and prerequisites of implementation include a reasonably high level of consumer acceptance, and the development of commercially-viable means of large scale production. Recent advancements in tissue culture techniques suggest that production may be economically feasible, provided it has physical properties in terms of colour, flavour, aroma, texture and palatability that are comparable to conventional meat. Although considerable progress has been made during recent years, important issues remain to be resolved, including the characterization of social and ethical constraints, the fine-tuning of culture conditions, and the development of culture media that are cost-effective and free of animal products. Consumer acceptance and confidence in in vitro produced cultured meat might be a significant impediment that hinders the marketing process.  相似文献