147 research outputs found
Strategies to attack pathogenic avian microorganisms: from probiotics to postbiotics
No full textTo reduce the growing risk of antimicrobial resistance, there is an increasing demand to substitute synthetic antimicrobial growth promoters in animal production with safer natural chemicals or biological alternatives. Therefore, this chapter will focus on the use of probiotics, prebiotics, synbiotics, and postbiotics in poultry production. Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Prebiotics are considered a substrate that is selectively utilized by host microorganisms, conferring a health benefit. They are thought to be hydrolyzed and then used by the gastrointestinal tract bacteria found in different parts of the avian gastrointestinal tract because they have been described as indigestible by the host. There are five categories of prebiotics: fructans, galactooligosaccharides, starch and glucose-derived oligosaccharides, other oligosaccharides, and non-carbohydrate or miscellaneous like cocoa-derived flavanols, polyphenolics, fatty acids, herbs, and other supplements. The most often used prebiotics in poultry include fructo-oligosaccharide, mannan-oligosaccharides, and galacto-oligosaccharides. A synbiotic is a mixture comprising live microorganisms and substrate(s) selectively utilized by host microorganisms, conferring a beneficial effect. There are complementary and synergistic synbiotics. In chickens, synbiotics can be supplemented in feed or water or injected in ovo to expedite colonization of the gut by beneficial bacteria. Finally, postbiotics are considered inactivated microbial cells or cell components, with or without their metabolites, that provide health benefits. Many existing postbiotics include inanimate strains belonging to established probiotic taxa within some genera of the family Lactobacillaceae or the genus Bifidobacterium. Postbiotics are composed of food-grade microorganisms or released after cell lysis in complex microbial cultures, food, or the intestinal lumen. All these products help support a healthy gut and immune system in poultry.EEA Concepción del UruguayFil: Bueno, Dante Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concepción del Uruguay; ArgentinaFil: Bueno, Dante Javier. Universidad Autónoma de Entre Ríos. Sede Basavilbaso. Facultad de Ciencia y Tecnología; ArgentinaFil: Latorre, Juan David. University of Arkansas Agricultural Experiment Station. Department of Poultry Science; Estados UnidosFil: Shehata, Awad A. Technical University of Munich (TUM). Bavarian NMR Center. Structural Membrane Biochemistry; AlemaniaFil: Eisenreich, Wolfgang. Technical University of Munich (TUM). Bavarian NMR Center. Structural Membrane Biochemistry; AlemaniaFil: Tellez-Isaias, Guillermo. University of Arkansas Agricultural Experiment Station. Department of Poultry Science; Estados Unido
Isolation of Salmonella from tissue and environmental samples and assessment of risk factors in commercial layers in Argentina
No full textThis study aimed to evaluate the isolation methods of Salmonella from tissues and environmental samples collected during natural Salmonella outbreaks in commercial layer farms in Argentina. We also assessed key risk factors for contamination with Salmonella serovar Gallinarum biovar Gallinarum (SG) in poultry houses. To achieve this, we collected tissue samples from 20 houses (n=398; including spleen, liver, ovary, cecal contents, and bone marrow) and environmental samples (n=510; including feed, eggs, feces, and water) from deceased laying hens and their surroundings. Various isolation procedures were employed using different media. Salmonella was identified based on biochemical tests and serotyping using agglutination tests. Results showed that out of 398 tissue samples, 247 (62%) were positive for SG: bone marrow (62/80), spleen (59/79), liver (57/80), ovary (51/80), and cecum 18/79). Salmonella spp. was detected in 25% (1/4), 17% (2/12), 10.6% (10/94), and 3.6% (4/110) in boot swabs, egg nests, feces, and feed, respectively. Additionally, samples of yolk egg pool (1/74) and eggshell pool (1/74) were positive for SG. Among isolated serovars, S. ser. Cerro was the most frequently isolated serovar, followed by SG, S. ser. Livingstone, S. ser. Enteritidis, S. ser. Derby, S. ser. Corvallis, S. ser. Infantis, S. ser. Mbandaka, S. ser. Montevideo, S. ser. Schwarzengrund, and S. ser. Heidelberg, which were all isolated from environmental samples. Notably, four poultry houses exhibited contamination with multiple serotypes, with three or four serotypes present. Multiple logistic regression analyses revealed that vaccination against SG and effective insect control notably decreased the spread of Salmonella on poultry farms. Our results emphasize the importance of using diverse sample types and detection techniques for isolating and identifying Salmonella. This data could also contribute to developing improved control programs and intervention strategies at the farm level to minimize Salmonella contamination in poultry.EEA Concepción del UruguayFil: Soria, Mario Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concepción del Uruguay; ArgentinaFil: Godano, Eduardo Ignacio. Universidad Autónoma de Entre Ríos. Facultad de Ciencia y Tecnología, Sede Crespo. Instituto Tecnológico Universitario; ArgentinaFil: Godano, Eduardo Ignacio. Tecnovo S.A., Entre Ríos; ArgentinaFil: Leiva, Leonardo Esteban. Grupo Motta, Entre Ríos; ArgentinaFil: Shehata, Awad A. Technical University of Munich (TUM). Bavarian NMR Center. Structural Membrane Biochemistry; AlemaniaFil: Bueno, Dante Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concepción del Uruguay; ArgentinaFil: Bueno, Dante Javier. Universidad Autónoma de Entre Ríos: Sede Basavilbaso. Facultad de Ciencia y Tecnología; Argentin
Adapting authoritarianism: institutions and co-optation in Egypt and Syria
No full textThis PhD thesis compares Egypt and Syria’s authoritarian political systems. While the tendency in social science political research treats Egypt and Syria as similarly authoritarian, this research emphasizes differences between the two systems with special reference to institutions and co-optation. Rather than reducibly understanding Egypt and Syria as sharing similar histories, institutional arrangements, or ascribing to the oft-repeated convention that “Syria is Egypt but 10 years behind,” this thesis focuses on how events and individual histories shaped each states current institutional strengthens and weaknesses. Specifically, it explains the how varying institutional politicization or de-politicization affects each state’s capabilities for co-opting elite and non-elite individuals.
Beginning with a theoretical framework that considers the limited utility of democratization and transition theoretical approaches, the work underscores the persistence and durability of authoritarianism. Chapter two details the politicized institutional divergence between Egypt and Syria that began in the 1970s. Chapter three and four examines how institutional politicization or de-politicization affects elite and non-elite individual co-optation in Egypt and Syria. Chapter five discusses the study’s general conclusions and theoretical implications.
This thesis’s argument is that Egypt and Syria co-opt elites and non-elites differently because of the varying degrees of institutional politicization in each governance system. Rather than view one country as more politically developed than the other, this work argues that Syria’s political institutions are more politicized than their Egyptian counterparts. Syria’s political arena is, thus, described as politicized-patrimonialism. Syria’s politicized-patrimonial arena produces uneven co-optation of elites and non-elites as they are diffused through competing institutions. Conversely, the Egyptian political arena remains highly personalized as weak institutions and individuals are manipulated and molded according to the president’s ruling clique. This is referred to as personalized-patrimonialism. As a consequence, Egypt’s political establishment demonstrates more flexibility in ad hoc altering and adapting its arena depending on the emergence of crises.
This study’s theoretical implications suggest that, contrary to modernization and democratization theory’s adage that institutions lead to a political development, politicized institutions within a patrimonial order actually hinder regime adaptation because consensus is harder to achieve and maintain. It is within this context that Egypt’s de-politicized institutional framework advantages its top political elite. In this reading of Egyptian and Syrian politics, Egypt’s personalized political arena is more adaptable than Syria’s. These conclusions do not indicate that political reform is a process underway in either state
Inhibition of the SARS-CoV-2 RNA-Dependent RNA polymerase by natural bioactive compounds: Molecular docking analysis
No full textCurrently, no approved treatment for COVID-19 exists. However, phenolic compounds exhibit antiviral activity. This study aimed to evaluate the activities of polyphenolic compounds (gallic acid, quercetin, caffeine, resveratrol, naringenin, benzoic acid, oleuropein, and ellagic acid) as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA-dependent RNA polymerase (PDB ID 6M71) inhibitors. Molecular docking simulations of these polyphenols were performed using Autodock 4.0 and Chimera 1.8.1. Drug-likeness and pharmacokinetic properties were calculated using the SWISSADME prediction website. Remdesivir and ribavirin were used for comparison. The docking analysis results, ranked by the binding energy value (ΔG) of the tested ligands toward SARS-CoV-2 polymerase, were remdesivir > gallic acid > quercetin > caffeine > ribavirin > resveratrol > naringenin > benzoic acid > oleuropein > ellagic acid, with binding energies of −8.51, −7.55, −7.17, −6.10, −6.01, −5.79, −5.69, −5.54, −4.94, and −4.59 kcal/mol, respectively. All tested polyphenols were predicted to form hydrogen bonds with one or two of the nucleotide triphosphate (NTP) entry channels at ARG 553, ARG 555, or LYS 545, except caffeine and oleuropein, which may influence the entry of substrate and divalent cations into the central active site cavity, thereby inhibiting enzyme activity. It appears promising that gallic acid and quercetin exhibited higher binding affinity than ribavirin toward the SARS-CoV-2 polymerase and expressed good drug-likeness and pharmacokinetic properties. Additionally, resveratrol, naringenin, and benzoic and ellagic acids exhibited some efficacy as potential polymerase inhibitors. Further research is required to investigate the potential uses of these polyphenols in the treatment of COVID-19
Truncated Sequences of Influenza Subtype H5 Haemagglutinin for Vaccination and Diagnostic Purposes: Avian influenza, Yeast expression, Peptide vaccination, recombinant Elisa
No full textThe highly pathogenic Avian Influenza subtype H5N1 can lead to 100 % mortality in chickens. The main issue in prevention of H5N1 is the development of efficient poultry vaccines. Influenza haemagglutinin (HA) derived recombinant polypeptides would not elicit an immune response against internal viral proteins. Thus HA polypeptide use facilitates differentiation between infected and vaccinated animals (DIVA). Serological tests using recombinant immune-dominant proteins devoid of non-specific moieties present in whole cell preparations might have higher sensitivity and specificity. In the present study, four non-overlapping sequences of different functional domains of influenza A virus subtype H5 virus (A / Thailand / 1 (Kan-1) / 2004) designated P1, P2, P5 and rHA1 were cloned and expressed in Pichia pastoris for vaccination and diagnosis purposes. The four polypeptides were expressed successfully in P. pastoris using peptone methanol (1 % (w/v) yeast extract, 2 % (w/v) peptone, 2 % (v/v) methanol). P1, P2 and rHA1 polypeptides were purified using nickel affinity chromatography, whereas, P5 was purified using lectin affinity chromatography. Correct expression was analysed by SDS-PAGE and western blot, glycosylation analysis and MALDI-TOF.The immune responses of P1, P2 and rHA1 polypeptides were assessed in BALB/C mice. To enhance antibody response, recombinant polypeptides were mixed with the Gerbu adjuvant and injected subcutaneously. Vaccination of mice induced high subtype specific antibody titres in mice as analysed by Elisa (using recombinant antigens or whole H5N1 antigen) and Immunofluorescence assay (IFA) performed on Vero cells infected with H5 (A / Thailand / 1 (Kan-1) / 2004). The immunogenicity of P1, P2, P5 and rHA1 polypeptides was determined in commercial layer chickens. Results showed that P1, P2 and rHA1 polypeptides induced high subtype specific antibody titres in chickens as analysed by Elisa (using recombinant antigens or whole H5N1 antigen), IFA (performed on Vero cells infected with H5N1 A / Thailand / 1 (Kan-1) / 2004) and microneutralization test (µNT). However, P5 polypeptide was not immunogenic in chickens. Neutralizing antibodies could be detected in chicken sera immunized with P1, P2 and rHA1 polypeptides as analyzed with microneutralization test. IgY was analysed in egg yolk of chickens immunized with recombinant polypeptides. The IgY of chicken immunized with P1 and rHA1, transferred to the egg yolk was proportional to maternal serum IgY. However, IgY could not be detected in egg yolk of chickens immunized with P2 and P5 recombinant polypeptides. The more immunogenic polypeptides P1 and rHA1 were used in an recombinant Elisa (rElisa) for detection of influenza A subtype H5 in chickens and duck sera.The optimal antigen for the concentrations of rHA1, P1 was 50 ng / well, 50 ng / well. Analysis of 25 positive sera and 25 negative sera to H5 antibodies revealed that, the sensitivity of Western blot, whole H5N1 Elisa, agar gel immunodiffusion test (AGID), P1-Elisa and rHA1-Elisa was 100 %, 100 %, 52 %, 80 % and 100 %, respectively, while the specificity was 100 %, 100 %, 100 %, 72 %, and 100 %, respectively. Moreover, duck sera, with haemagglutination inhibiting titer ranged from 4 - 8 log2, were tested positive by rHA1 Elisa compared with negative duck sera. Further analysis of 179 serum samples with rHA1-Elisa in comparison with haemagglutination inhibition (HI) and commercial Elisa proved to be highly sensitive and specific. The agreement ratio between rElisa and HI was 84.9 % and between commercial Elisa (Flock check) and HI was 76.5 %. In conclusion, P. pastoris may allow development of an effective recombinant influenza vaccine based on truncated sequences of HA that might provide broader protection against H5 influenza viruses. The possibilities to use rHA1, P1 and P5 recombinant polypeptides as a vaccine against H5 influenza should be further studied. Also our study demonstrates the potential utility of recombinant Elisa as a tool for improvement of serological diagnosis of influenza A subtype H5 in chickens and ducks.Die hochpathogene aviäre Influenza des Subtyps H5N1 erreicht beim Ausbruch von Infektionen in Nutzgeflügelbeständen Mortalitätsraten von bis zu 100 %. Effektive und kostengünstige Impfstoffe werden benötigt, die möglichst auch eine Differenzierung zwischen geimpften Tieren und mit Wild-Virus infizierten Tieren zulassen. In diesem Zusammenhang könnten Peptid-Vakzine eine mögliche Alternative zu den herkömmlichen Impfstoffen darstellen, bei denen unter Verwendung des Vollvirus Antikörper gegen mehrere Virusproteine induziert werden. Außerdem, könnten rekombinante Antigene in serologischen Tests zur Diagnose von H5 Virus in Nutzgeflügel eingesetzt werden. Von dem Einsatz spezifischer rekombinanter Antigene ist eine Verbesserung der Serodiagnostik zu erwarten. In dieser Arbeit, wurden vier verkürzte Sequenzen des Hämagglutinins (P1, P2, P5 und rHA1) von Subtyp H5 (A / Thailand / 1 (Kan-1) / 2004) rekombinant in Pichia Pastoris exprimiert. Dazu erfolgten zunächst eine Klonierung in der Expressionsvektor pAOX und die Transformation von Pichia Pastoris. Die Expression wurde durch Methanol induziert. Der Nachweis der rekombinanten Fusionspeptiden mit C-terminalen Histidin-Tag erfolgte durch SDS-PAGE, Western Blot, Glycolysierungsanalyse, und MALDI-TOF. Der Histidin-Tag ermöglichte die Reinigung von P1, P2 und rHA1 mit Metall-Affinitätschromatographie. Polypeptid P5 hingegen wurde mittels Lectin-Affinitäts- chromatographie gereinigt. Balb/c Mäuse wurden mit Polypeptid P1, P2 bzw. rHA1, versetzt mit Gerbu Adjuvans, immunisiert. Zur Untersuchung der Immunantwort wurden die murinen Seren mittels Elisa (unter Verwendung rekombinanter Antigene oder Voll-H5N1 Antigen) sowie IFA (durchgeführt in Vero- Zellen infiziert mit A / Thailand / 1 (Kan-1) / 2004) analysiert. Dabei wurde die präferentielle Induktion von H5-spezifischen Antikörpern detektiert. Die Immunogenität der P1, P2, P5 und rHA1-Polypeptide wurde in kommerziellen Legehennen bestimmt. Seren wurden mit ELISA, IFA, und Mikroneutralizationstest (μNT) analysiert. Die ELISA-Ergebnisse zeigten, dass die Polypeptide P1, P2 und rHA1 hohe Subtyp-spezifische Antikörpertiter in Hühnern induzierten. Im µNT konnte nur ein niedriger neutralisierender Antikörpertiter nachgewiesen werden. Das P5- Polypeptid ist bei Hühnern nicht immunogen. Im Eigelb von Hühnern, die mit den rekombinanten Polypeptiden P1 und rHA1 immunisiert wurden, konnten H5-spezifische IgY Antikörper detektiert werden. Hühner, die mit P2 und P5 immunisiert wurden, zeigten keine IgY im Eigelb. Die rekombinanten Antigene P1 und rHA1 wurden im ELISA auf ihre potenzielle Eignung für die Serodiagnostik untersucht. Die optimale Antigenkonzentration war 50 ng / well. Die serologische Analyse von 25 positiven und 25 negativen Seren auf Antikörper gegen H5 zeigte, dass Sensitivität und Spezifität von Western Blot, Voll-H5N1 ELISA und rHA1-ELISA bei jeweils 100 % lagen. Bei Agargel- Immunodiffusiontest (AGID) lagen Sensitivität und Spezifität bei 52 % und 100 %, während im P1-Elisa lediglich eine Sensitivität von 80 % und eine Spezifität von 72 % erreicht wurden. Somit eignet sich rHA1 für die Anwendung in der Serodiagnostik. Bei der serologischen Untersuchung von 175 Hühnerseren wurde eine Überbestimmung zwischen rHA1-ELISA und Hämagglutinationshemmungstest (HAI) 84.9 % festgestellt, während diese zwischen dem kommerziellen ELISA (Flock Check) und HAI 76.5 % betrug. Die Ergebnisse zeigten, dass das Expressionssystem P. pastoris als Produktionssystem rekombinanter Antigene für die Serodiagnostik von H5 Influenza geeignet ist. Challenge-Versuche sind nötig, um die Eignung von rekombinanten Antigenen als möglichen Impfstoff gegen H5 Influenza zu untersuchen
MITES IN MARJORAM AND CHAMOMILE CULTIVATIONS IN FAYOUM AND THE RELATIVE ABUNDANCE OF TWENTY SIX SPECIES
No full textA study on mite species in marjoram and chamomile plantations in Fayoum was carried out during 2003 and 2004 seasons. Twenty-six species were found and divided according to their feeding habits into three major groups, phytophagous (7 species), predaceous (8 species) and a group of debatable feeding habits (11 species). Population density evaluation showed that Tetranychus urticae Koch was the main phytophagous mite on both hosts. The predatory mite Amblyseius cydnodactylon Shehata and Zaher was dominant on marjoram followed by Hemicheyletia bakeri (Ehara). From the debatable group, Pronematus ubiquitus Mc Gregor was the dominant followed by Tyrophagus putrescentiae (Schrank) and Paralorryia gizai El-Bagoury. On chamomile, the predatory mite Eupodes niloticus Abou-Awad & El-Bagoury was dominant and from the debatable group, Tydeus kochi Oud. was dominant followed by T. putrescentiae and P. gizai. Population densities were insignificantly affected by temperature and relative humidity
Nutraceuticals to Mitigate the Secret Killers in Animals
No full textIn the past few years, the concept of “gut health” has established itself as a norm in the scientific literature and animal production [...
A Search Space Toolkit
No full textThe Search Space Toolkit (SST) is a suite of tools for investigating the properties of the continuous search spaces which arise in designing complex engineering artifacts whose evaluation requires significant computation by a numerical simulator. SST has been developed as part of NDA, a computational environment for (semi-)automated design of jet engine exhaust nozzles for supersonic aircraft, which was developed in a collaboration between computer scientists at Rutgers University and design engineers at General Electric and Lockheed. Though the design spaces for this sort of engineering artifact are mainly continuous, they typically include features such as unevaluable points, multiple local optima, and large derivatives which cause difficulties for standard numerical optimization methods. The search spaces which SST explores also differ significantly from the discrete search spaces that typically arise in artificial intelligence research, and properly searching such spaces requires a synergistic combination of numerical methods and AI techniques and is a fundamental AI research area. By promoting the design space to be a first class entity, rather than a ``black box'' buried in the interface between an optimizer and a simulator, SST allows a more principled approach to automated design.Technical report hpcd-tr-2
The COVID-19 Pandemic: A Comprehensive Review of Taxonomy, Genetics, Epidemiology, Diagnosis, Treatment, and Control
No full textA pneumonia outbreak with unknown etiology was reported in Wuhan, Hubei province, China, in December 2019, associated with the Huanan Seafood Wholesale Market. The causative agent of the outbreak was identified by the WHO as the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), producing the disease named coronavirus disease-2019 (COVID-19). The virus is closely related (96.3%) to bat coronavirus RaTG13, based on phylogenetic analysis. Human-to-human transmission has been confirmed even from asymptomatic carriers. The virus has spread to at least 200 countries, and more than 1,700,000 confirmed cases and 111,600 deaths have been recorded, with massive global increases in the number of cases daily. Therefore, the WHO has declared COVID-19 a pandemic. The disease is characterized by fever, dry cough, and chest pain with pneumonia in severe cases. In the beginning, the world public health authorities tried to eradicate the disease in China through quarantine but are now transitioning to prevention strategies worldwide to delay its spread. To date, there are no available vaccines or specific therapeutic drugs to treat the virus. There are many knowledge gaps about the newly emerged SARS-CoV-2, leading to misinformation. Therefore, in this review, we provide recent information about the COVID-19 pandemic. This review also provides insights for the control of pathogenic infections in humans such as SARS-CoV-2 infection and future spillovers
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