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1.
Nanoscale Adv ; 5(21): 5952-5964, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37881705

RESUMEN

The Soret and Dufour effects have significant importance in several practical scenarios, especially in the domain of fluidic mass and temperature transfer. Nanofluidics, biological systems, and combustion processes are all areas where these consequences are crucial. Because of its distinct geometry, a wedge-shaped structure has aerodynamics, production, and engineering applications. Wedge shapes are used in aerodynamics for analyzing and improving airflow across various objects. Nanofluids increase thermal conductivity over traditional fluids making them ideal for cooling high-power electronics, boosting temperature transfer efficiencies, and boosting the solar energy system output. This work is of critical importance since it examines the consequences of a heat source/sink, the Soret impact and the Dufour impact, on the movement of a ternary nanofluid over a wedge. This work uses appropriate similarity constraints to reduce the complexity of the underlying governing equations, allowing for fast computational solutions with the Runge-Kutta-Fehlberg 4-5th order method (RKF-45). Analysis of these phenomena helps determine their possible real-world applications across various engineering fields, by presenting numerical results through plots. The results reveal that adjusting the moving wedge factor lessens the temperature profile, improving the magnetic constraint increases the velocity, and modifying the heat source/sink, Dufour, and Soret factors increases the temperature and concentration profiles. Dufour and heat source/sink constraints speed-up the heat transmission rate. In all cases, ternary nano liquids show significant performance over hybrid nano liquids.

2.
Sci Rep ; 13(1): 14795, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684341

RESUMEN

Access to dependable and environmentally friendly energy sources is critical to a country's economic growth and long-term development. As countries seek greener energy alternatives, the interaction of environmental elements, temperature, and sunlight becomes more critical in utilizing renewable energy sources such as wind and bioenergy. Solar power has received much attention due to extraordinary efficiency advances. under this context, the present work focus on solar radiation and chemical processes in the presence of modified ternary hybrid nanofluids (THNFs) circulating over an exponentially stretched surface in both aiding flow (A-F) and opposing flow (O-F) circumstances. The primary objective of this investigation is to dive into the complicated dynamics of these structures, which are distinguished by complex interactions involving radiation, chemical reactions, and the movement of fluids. We construct reduced ordinary differential equations from the governing equations using suitable similarity transformations, which allows for a more in-depth examination of the liquid's behavior. Numerical simulations using the Runge-Kutta Fehlberg (RKF) approach and shooting techniques are used to understand the underlying difficulties of these reduced equations. The results show that thermal radiation improves heat transmission substantially under O-F circumstances in contrast to A-F conditions. Furthermore, the reaction rate parameter has an exciting connection with concentration levels, with greater rates corresponding to lower concentrations. Furthermore, compared to the O-F scenario, the A-F scenario promotes higher heat transfer in the context of a modified nanofluid. Rising reaction rate and solid fraction volume enhanced mass transfer rate. The rate of thermal distribution in THNFs improves from 0.13 to 20.4% in A-F and 0.16 to 15.06% in O-F case when compared to HNFs. This study has real-world implications in several fields, including developing more efficient solar water heaters, solar thermal generating plants, and energy-saving air conditioners.

3.
Biomimetics (Basel) ; 8(8)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38132513

RESUMEN

Evolutionary algorithms are a large class of optimization techniques inspired by the ideas of natural selection, and can be employed to address challenging problems. These algorithms iteratively evolve populations using crossover, which combines genetic information from two parent solutions, and mutation, which adds random changes. This iterative process tends to produce effective solutions. Inspired by this, the current study presents the results of thermal variation on the surface of a wetted wavy fin using a genetic algorithm in the context of parameter estimation for artificial neural network models. The physical features of convective and radiative heat transfer during wet surface conditions are also considered to develop the model. The highly nonlinear governing ordinary differential equation of the proposed fin problem is transmuted into a dimensionless equation. The graphical outcomes of the aspects of the thermal profile are demonstrated for specific non-dimensional variables. The primary observation of the current study is a decrease in temperature profile with a rise in wet parameters and convective-conductive parameters. The implemented genetic algorithm offers a powerful optimization technique that can effectively tune the parameters of the artificial neural network, leading to an enhanced predictive accuracy and convergence with the numerically obtained solution.

4.
Avian Dis ; 65(2): 227-236, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34412452

RESUMEN

The history of pullorum disease is closely intertwined with the history of avian health research and that of the poultry industry. The seriousness of the disease galvanized the attention and brought together, for the first time, the pioneers of poultry health research to work cooperatively on different aspects of the disease. Control of the disease made it possible for intensive poultry production to develop as the basis for the modern poultry industry. During the early 1900s, bacillary white diarrhea (BWD) was a devastating disease of young chickens threatening the developing poultry industry. Dr. Leo F. Rettger isolated and described the bacterial pathogen, Salmonella enterica serotype Pullorum, for the first time in 1900. BWD was renamed pullorum disease in 1929. In subsequent years, Rettger and coworkers were able to reproduce the disease and fulfill Koch's postulates. Rettger et al. also showed that Salmonella Pullorum was vertically transmitted, which was the first time that a pathogen was shown to be vertically transmitted. The development of serologic tests was of crucial importance because it led to the development of effective eradication methods to identify carrier birds and to exclude these birds from the breeder flocks. The negative impact of pullorum disease on the poultry industry ultimately was one of the major reasons that the National Poultry Improvement Plan (NPIP) was developed by scientists, the poultry industry, and the United States Department of Agriculture (USDA). Needless to say, the work of the pioneering researchers formed the basis for the control of the disease. The NPIP started in 1935, with 34 states participating in testing 4 million birds representing 58.2% of the birds hatched. The program rapidly expanded to 47 states by 1948 and tested more than 30 million birds. In 1967, all commercial chicken hatcheries participating in the NPIP were 100% free of pullorum and typhoid disease caused by Salmonella enterica serotype Gallinarum. This historical overview of pullorum disease describes in some detail the progress made, especially during the early years, toward controlling this disease using methodologies that were often very basic but nonetheless effective. One has to admire the ingenuity and persistence of the early researchers leading to their achievements considering the research tools that were available at the time.


Artículo histórico­Pulorosis: Evolución de las estrategias de erradicación La historia de la pulorosis está estrechamente relacionada con la historia de la investigación en salud aviar y de la industria avícola. La severidad de la enfermedad despertó la atención y reunió, por primera vez a los pioneros de la investigación en salud avícola para trabajar de manera cooperativa en diferentes aspectos de la enfermedad. El control de la enfermedad hizo posible que la producción avícola intensiva se desarrollara como base de la industria avícola moderna. A principios de la década de los 1900, la diarrea blanca bacilar (con las siglas en inglés BWD) era una enfermedad devastadora de pollos jóvenes que amenazaba la industria avícola en desarrollo. El Dr. Leo F. Rettger aisló y describió el patógeno bacteriano, Salmonella enterica serotipo Pullorum, por primera vez en 1900. La diarrea blanca bacilar pasó a llamarse pulorosis (pullorum disease) en 1929. En los años siguientes, Rettger y sus colaboradores pudieron reproducir la enfermedad y cumplir los postulados de Koch. Rettger y col. también mostraron que Salmonella Pullorum se transmitía verticalmente, y fue la primera vez que se demostró que un patógeno se transmitía verticalmente. El desarrollo de pruebas serológicas fue de crucial importancia porque condujo al desarrollo de métodos de erradicación efectivos para identificar aves portadoras y eliminar a estas aves de las parvadas reproductoras. El impacto negativo de la pulorosis en la industria avícola fue, en última instancia, una de las principales razones por las que los científicos, la industria avícola y el Departamento de Agricultura de los Estados Unidos (USDA) desarrollaron el Plan Nacional de Mejoramiento Avícola (NPIP). Es importante decir que el trabajo de los investigadores pioneros formó la base para el control de la enfermedad. El Plan Nacional de Mejoramiento Avícola comenzó en año 1935, con 34 estados participando en el análisis de 4 millones de aves que representaban el 58.2% de las aves producidas. El programa se expandió rápidamente a 47 estados en 1948 y evaluó a más de 30 millones de aves. En 1967, todas las plantas incubadoras de pollos comerciales que participaban en el Plan Nacional de Mejoramiento Avícola estaban 100% libres de pulorosis y tifoidea aviar causada por Salmonella enterica serotipo Gallinarum. Esta reseña histórica de la pulorosis describe con cierto detalle el progreso realizado, especialmente durante los primeros años, hacia el control de esta enfermedad utilizando metodologías que a menudo eran muy básicas no obstante efectivas. Es admirable el ingenio y la persistencia de los primeros investigadores que los llevaron a sus logros considerando las herramientas de investigación que estaban disponibles en ese momento.


Asunto(s)
Pollos , Enfermedades de las Aves de Corral/prevención & control , Salmonelosis Animal/prevención & control , Salmonella/clasificación , Factores de Edad , Animales , Historia del Siglo XX , Transmisión Vertical de Enfermedad Infecciosa/historia , Transmisión Vertical de Enfermedad Infecciosa/veterinaria , Enfermedades de las Aves de Corral/diagnóstico , Enfermedades de las Aves de Corral/historia , Enfermedades de las Aves de Corral/transmisión , Salmonella/patogenicidad , Salmonelosis Animal/historia , Salmonelosis Animal/microbiología , Salmonelosis Animal/transmisión
5.
J Food Prot ; 69(6): 1463-7, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16786876

RESUMEN

In a multicenter study conducted by the Indian Council of Medical Research, 1,646 samples of wheat grain collected from rural and urban areas of 10 states representing different geographical regions of India were analyzed for aflatoxin B1 (AFB1). AFB1 concentrations of > or = 5 microg kg(-1) were recorded in 40.3% of the samples, and concentrations above the Indian permissible regulatory limit of 30 microg kg(-1) were found in 16% of the samples. The proportion of samples with AFB1 concentrations above the Indian regulatory limit ranged from 1.7 to 55.8% in different states, with the minimum in Haryana and the maximum in Orissa. The variation in wheat contamination among states seems to be mainly the result of unsatisfactory storage conditions. Median AFB1 concentrations of 11, 18, and 32 microg kg(-1) were observed in samples from Uttar Pradesh, Assam, and Orissa, respectively; concentrations in other states were <5 microg kg(-1). The maximum AFB1 concentration of 606 microg kg(-1) was observed in a sample from the state of Uttar Pradesh. The calculated probable daily intakes of AFB1 through consumption of contaminated wheat for the population in some states were much higher than the suggested provisional maximum tolerable daily intake. Human health hazards associated with such AFB1 exposure over time cannot be ruled out.


Asunto(s)
Aflatoxina B1/aislamiento & purificación , Seguridad de Productos para el Consumidor , Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Venenos/aislamiento & purificación , Triticum/química , Aflatoxina B1/análisis , Microbiología de Alimentos , Humanos , Incidencia , India , Concentración Máxima Admisible , Venenos/análisis , Triticum/microbiología
6.
Diagn Microbiol Infect Dis ; 14(3): 203-8, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1832368

RESUMEN

An agar gel enzyme assay (AGEA) was developed for the detection of antibodies to Salmonella enteritidis (SE). The assay was based on the ability of antibodies to diffuse through an agar gel and react with antigen coated on a polystyrene surface. The antigen-antibody reaction was then made visible by applying an enzyme-conjugated anti-immunoglobulin and the addition, subsequently, of a substrate-containing gel. The color change in circular zones was taken as the indication for the presence of antibodies. The present investigation reports identification of an antigen specific for SE and its use in the development of a relatively simple AGEA procedure. The results of AGEA were compared with those of conventional microagglutination (MA) test and serum plate (SP) test. The percentage agreement between MA and AGEA in positive serum sample was found to be 94.4%, and in negative serum samples it was found to be 88.8%. The present results suggest that the AGEA could be a very useful screening test for the detection of SE antibodies because the assay is inexpensive, specific and simple to perform without much equipment, and give results within a 3-hr period.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Pollos , Enfermedades de las Aves de Corral/diagnóstico , Salmonelosis Animal/diagnóstico , Salmonella enteritidis/inmunología , Pruebas de Aglutinación , Animales , Antígenos Bacterianos/inmunología , Sueros Inmunes/inmunología , Inmunodifusión , Técnicas para Inmunoenzimas , Valor Predictivo de las Pruebas , Organismos Libres de Patógenos Específicos
7.
Diagn Microbiol Infect Dis ; 32(3): 147-57, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9884830

RESUMEN

A number of disease outbreaks of Salmonella enterica serotype enteritidis (SE) in humans have been traced to the consumption of SE-contaminated egg and egg products. A rapid, specific, and inexpensive method of detecting SE infection in poultry is necessary to reduce human outbreaks. We evaluated rSEF14 fimbrial antigen of SE for specific detection of SE-infected birds in latex agglutination test and enzyme-linked immunosorbent assay. rSEF14 antigen was highly specific in identifying birds infected with SE. The sera from birds infected with closely related serogroup-D Salmonella and other avian pathogens did not react with rSEF14 antigen. The rSEF14 antigen identified antibodies in serum of 88% of birds during the first 2 weeks of infection, and 100% of the birds subsequently. The SE-specific antibodies were detected in egg yolk as early as 6 days post-infection in rSEF14-enzyme-linked immunosorbent assay. Our results suggest that rSEF14-based assays could be used as screening tests for detection of SE antibodies and would overcome the cross reactions observed with existing serological tests.


Asunto(s)
Proteínas Bacterianas/inmunología , Pollos , Proteínas Fimbrias , Enfermedades de las Aves de Corral/diagnóstico , Salmonelosis Animal/diagnóstico , Salmonella enteritidis/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Anticuerpos Antibacterianos/análisis , Anticuerpos Antibacterianos/biosíntesis , Antígenos Bacterianos/química , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Cartilla de ADN/química , ADN Bacteriano/química , Yema de Huevo/microbiología , Electroforesis en Gel de Poliacrilamida/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Heces/microbiología , Fimbrias Bacterianas/química , Fimbrias Bacterianas/inmunología , Pruebas de Fijación de Látex/veterinaria , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de las Aves de Corral/microbiología , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Intoxicación Alimentaria por Salmonella/prevención & control , Salmonella enteritidis/genética , Salmonella enteritidis/inmunología , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Organismos Libres de Patógenos Específicos
8.
J Med Microbiol ; 47(6): 489-97, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9879967

RESUMEN

The presence of a Salmonella serotype Enteritidis repeat element (SERE) located within the upstream regulatory region of the sefABCD operon encoding fimbrial proteins is reported. DNA dot-blot hybridisation analyses and computerised searches of genetic databases indicate that SERE is well conserved and widely distributed throughout the bacterial and archaeal kingdoms. A SERE-based polymerase chain reaction (SERE-PCR) assay was developed to fingerprint 54 isolates of Enteritidis representing nine distinct phage types and 54 isolates of other Salmonella serotypes. SERE-PCR identified five distinct fingerprint profiles among the 54 Enteritidis isolates; no correlation between phage types and SERE-PCR fingerprint patterns was noticed. SERE-PCR was reproducible, rapid and easy to perform. The results of this investigation suggest that the limited heterogeneity of SERE-PCR fingerprint patterns can be utilised to develop serotype- and serogroup-specific fingerprint patterns for isolates of Enteritidis.


Asunto(s)
ADN Bacteriano/genética , Secuencias Repetitivas Esparcidas , Reacción en Cadena de la Polimerasa/métodos , Salmonella enteritidis/genética , Animales , Secuencia de Bases , Secuencia de Consenso , Dermatoglifia del ADN , Cartilla de ADN/genética , ADN Bacteriano/química , Humanos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Operón , Reacción en Cadena de la Polimerasa/estadística & datos numéricos , Reproducibilidad de los Resultados , Fagos de Salmonella/clasificación , Fagos de Salmonella/genética , Salmonella enteritidis/clasificación , Salmonella enteritidis/aislamiento & purificación , Homología de Secuencia de Ácido Nucleico , Serotipificación
9.
Int J Food Microbiol ; 53(1): 53-60, 1999 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-10598114

RESUMEN

A rapid strip immunoblot assay (RSIA) was developed using recombinant SEF14 antigen. The rSEF14-RSIA was very specific in detecting antibodies to Salmonella enteritidis in chickens. When serum samples obtained from groups of chickens (N = 5) inoculated with six different Salmonella serovars were tested in rSEF14-RSIA, only serum samples obtained from S. enteritidis inoculated birds reacted with rSEF14 antigen except for a group of chickens that had been inoculated with S. dublin. To assess the sensitivity of the rSEF14-RSIA, groups of chickens were inoculated with either 10(4) cfu or 10(10) cfu of S. enteritidis and the serum and egg yolk were analyzed for SEF14 antibodies. By 1 week after infection 66-78% of chickens were found positive for SEF14 antibodies in the serum and the number of positive birds increased subsequently to 89-100%. The S. enteritidis specific antibodies appeared as early as 6 days after infection in the egg yolk of infected chickens. The antibodies to SEF14 in both the serum and egg yolk persisted for at least 7 weeks after infection in a significant proportion of chickens. Our results suggest that rSEF14-RSIA can be a practical and efficient screening test for identifying S. enteritidis infected chickens.


Asunto(s)
Proteínas Fimbrias , Enfermedades de las Aves de Corral/diagnóstico , Salmonelosis Animal/diagnóstico , Salmonella enteritidis/aislamiento & purificación , Animales , Anticuerpos Antibacterianos/análisis , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Pollos , Yema de Huevo/microbiología , Técnicas de Inmunoadsorción , Pili Sexual/inmunología , Proteínas Recombinantes/inmunología , Salmonella enteritidis/inmunología
10.
Vet Microbiol ; 34(1): 19-34, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8447077

RESUMEN

The extent of genetic differentiation among 80 Escherichia coli isolates collected from turkeys with acute colisepticemia was assessed based on allelic variation at 20 enzyme-encoding loci detected by multilocus enzyme electrophoresis. Isolates were polymorphic at 17 loci and were classified into 32 multilocus genotypes, delineating clones, that differed on average at 36% of the loci. In the total sample, 29 (36%) of the isolates belonged to one of two closely related clones, differing only in a single electromorph, and 11 of these isolates were serogroup O78. Most isolates fell into one of 4 genetically distinct clusters of strains. Three of these clusters represent E. coli clone complexes that have been previously identified in avian diseases and a fourth cluster which is specific to colisepticemia in turkeys. Most (73%) isolates produced aerobactin, whereas none produced hemolysins. Assays for detecting K1 capsules, including the use of polyclonal antisera, monoclonal antibodies, and K1-specific bacteriophages, gave variable results, but showed that overall 18% of the strains from colisepticemia were K1 encapsulated with most of the K1+ isolates found in one clone cluster. The results show that many cases of colisepticemia in turkey flocks are caused by a small number of pathogenic clones representing at least three distinct clone complexes.


Asunto(s)
Bacteriemia/veterinaria , Infecciones por Escherichia coli/veterinaria , Escherichia coli/genética , Variación Genética , Enfermedades de las Aves de Corral/microbiología , Pavos , Animales , Antígenos Bacterianos/análisis , Bacteriemia/microbiología , Cápsulas Bacterianas/inmunología , Escherichia coli/química , Escherichia coli/enzimología , Infecciones por Escherichia coli/genética , Ligamiento Genético , Ácidos Hidroxámicos/análisis , Polimorfismo Genético , Serotipificación
11.
J Food Prot ; 63(2): 155-61, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10678417

RESUMEN

Salmonella Typhimurium isolates from feed ingredients or poultry sources isolated during 1995 to 1997 from different geographical locations within Minnesota were examined for the presence of Salmonella Typhimurium definitive type 104 (DT104). Antibiotic susceptibility studies indicated that 15 of 50 isolates of Salmonella Typhimurium had an antibiotic resistance pattern (ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline) that is usually observed with multidrug-resistant Salmonella Typhimurium DT104. Of the 15 isolates showing the antibiotic resistance pattern, 8 isolates were phage type 104, 3 isolates were typed as phage type 104 complex, and the remaining 4 isolates belonged to phage types 193, 81, and 126. DT104 was recovered from both feed ingredients and poultry samples. Of the seven feed ingredient-associated Salmonella Typhimurium isolates, four were DT104, whereas only 7 of 43 poultry-associated Salmonella Typhimurium isolates were DT104. A repetitive sequence-based polymerase chain reaction (rep-PCR) of 50 isolates of Salmonella Typhimurium representing 13 phage types identified seven distinct fingerprint profiles. No correlation between phage type and rep-PCR type was noticed. Eleven Salmonella Typhimurium isolates belonging to DT104 and its complex were grouped into two closely related rep-PCR types.


Asunto(s)
Aves de Corral/microbiología , Salmonella typhimurium/aislamiento & purificación , Animales , Antibacterianos/farmacología , Tipificación de Bacteriófagos , Farmacorresistencia Microbiana , Resistencia a Múltiples Medicamentos , Salmonella typhimurium/efectos de los fármacos
12.
J Vet Diagn Invest ; 8(3): 310-4, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8844573

RESUMEN

A dot immunobinding assay (DIA) was developed for the detection of antibodies to Salmonella enteritidis. Western blot analysis of outer membrane proteins from SE identified 2 polypeptides of molecular masses 43 and 46 kD that were specific for S. enteritidis. These 2 polypeptides were utilized as antigens in the DIA. The DIA was tested on sera from chickens experimentally infected with S. enteritidis. Results of the DIA were compared with that of conventional microagglutination and serum plate tests. The DIA was a highly specific and sensitive test that can be useful for screening birds to determine if they are infected with S. enteritidis. Its simplicity, reliability, reproducibility, and speed in interpreting the assay results makes it a useful screening test for flock monitoring.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Enfermedades de las Aves de Corral , Salmonelosis Animal/diagnóstico , Salmonella enteritidis/aislamiento & purificación , Animales , Proteínas de la Membrana Bacteriana Externa/inmunología , Pollos , Ensayo de Inmunoadsorción Enzimática/métodos , Sensibilidad y Especificidad , Factores de Tiempo
13.
J Vet Diagn Invest ; 13(1): 13-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11243355

RESUMEN

An immunohistochemical staining technique (IHC) was developed to detect avian pneumovirus (APV) antigen in formalin-fixed, paraffin-embedded tissue sections using streptavidin-biotin immunoperoxidase staining. Samples of nasal turbinates and infraorbital sinuses were collected from 4-week-old poults experimentally inoculated with APV and from older turkeys infected during naturally occurring outbreaks of avian pneumovirus. Tissue was fixed in 10% buffered neutral formalin, embedded in paraffin, sectioned and stained. Inflammatory changes were observed microscopically in the mucosa and submucosa of the nasal turbinates and infraorbital sinuses of both experimentally inoculated poults and naturally infected birds. Viral antigen was detected by IHC in the ciliated epithelial cells of nasal turbinates and infraorbital sinuses.


Asunto(s)
Infecciones por Pneumovirus/veterinaria , Pneumovirus/aislamiento & purificación , Enfermedades de las Aves de Corral/diagnóstico , Animales , Antígenos Virales/análisis , Femenino , Formaldehído , Inmunohistoquímica , Masculino , Mucosa Nasal/virología , Pneumovirus/inmunología , Infecciones por Pneumovirus/diagnóstico , Conejos/inmunología , Fijación del Tejido , Pavos
14.
J Vet Diagn Invest ; 12(2): 166-8, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10730950

RESUMEN

Antibodies to avian pneumovirus (APV) were first detected in Minnesota turkeys in 1997. Virus isolation was attempted on 32 samples (28 tracheal swabs, 4 pools of trachea and turbinates) that were positive for APV by reverse transcriptase polymerase chain reaction (RT-PCR). The cell cultures used were chicken embryo fibroblast (CEF), Vero cells, and QT-35 cells. Five virus isolates were obtained from these samples, and the identity of the isolates was confirmed by RT-PCR. Four isolates were obtained by inoculation of CEF cells, and 1 isolate was obtained in QT-35 cells after 3-7 blind passages in cell cultures. Vero cells did not yield any isolate on primary isolation; however, all 5 isolates could be adapted to grow in Vero cells following primary isolation in CEF or QT-35 cells. This is the first report of isolation of APV in Minnesota and also the first report of primary isolation of APV in QT-35 cells.


Asunto(s)
Enfermedades de las Aves/virología , Infecciones por Pneumovirus/veterinaria , Pneumovirus/aislamiento & purificación , Pavos/virología , Animales , Embrión de Pollo , Brotes de Enfermedades/veterinaria , Minnesota/epidemiología , Infecciones por Pneumovirus/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
15.
J Vet Diagn Invest ; 12(4): 381-4, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10907873

RESUMEN

Avian pneumovirus (APV) infection of turkeys in Minnesota was first confirmed in March 1997. Serum samples (n = 5,194) from 539 submissions to Minnesota Veterinary Diagnostic Laboratory were tested by a modified enzyme-linked immunosorbent assay (ELISA). Of these, 2,528 (48.7%) samples from 269 submissions were positive and 2,666 (51.3%) samples from 270 submissions were negative for APV antibodies. Most positive samples were from Kandiyohi, Stearns, Morrison, and Meeker counties in Minnesota. In addition, 10 samples from South Dakota were positive. The sensitivity and specificity of the ELISA test with anti-chicken and anti-turkey conjugates were compared by testing field and experimental sera. The ELISA test with anti-turkey conjugate was more sensitive than that with anti-chicken conjugate. The ELISA tests with antigens prepared with APV strains isolated from Colorado and Minnesota were also compared. No difference was detectable. Currently, the Minnesota Veterinary Diagnostic Laboratory uses an antigen prepared from the Colorado isolate of APV and a goat anti-turkey conjugate in the ELISA test.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/veterinaria , Infecciones por Pneumovirus/veterinaria , Pneumovirus , Enfermedades de las Aves de Corral/diagnóstico , Animales , Anticuerpos Antivirales/análisis , Pollos , Ensayo de Inmunoadsorción Enzimática/métodos , Pneumovirus/inmunología , Infecciones por Pneumovirus/diagnóstico , Infecciones por Pneumovirus/inmunología , Enfermedades de las Aves de Corral/inmunología , Sensibilidad y Especificidad , Pavos
16.
Avian Dis ; 37(2): 477-84, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8363512

RESUMEN

Immunostaining complexes (ISCOMs) are multimeric particles and have been used successfully for presentation of membrane proteins. In this study, outer-membrane proteins (OMPs) from Salmonella heidelberg were incorporated into lipid-conjugated ISCOM particles and evaluated for their use in a vaccine for turkeys against homologous and heterologous Salmonella challenge. Two types of lipid-conjugated ISCOMs were examined: ISCOM-phospholipid and ISCOM-sphingolipid preparations. The turkeys were challenged with one of the three Salmonella serotypes: S. heidelberg, S. reading, or S. enteritidis. The turkeys were monitored for clinical signs, shedding pattern post-challenge, and clearance of the challenge Salmonella from selected internal organs. Vaccines containing OMP with either lipid-conjugated ISCOM preparation produced significantly greater (P < 0.01) immune response than OMP alone. Cloacal swabs from turkeys given OMP along with ISCOM-phospholipid and challenged with a homologous serotype were completely negative for Salmonella. A certain degree of cross-protection against heterologous Salmonella was afforded by both OMP-ISCOM vaccines. The isolation rate of Salmonella from internal organs was significantly lower (P < 0.0001) in vaccinated turkeys than in unvaccinated controls.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Proteínas de la Membrana Bacteriana Externa/administración & dosificación , Vacunas Bacterianas/administración & dosificación , ISCOMs/administración & dosificación , Enfermedades de las Aves de Corral/prevención & control , Salmonelosis Animal/prevención & control , Salmonella/inmunología , Pavos/inmunología , Animales , Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/inmunología , ISCOMs/inmunología , Microscopía Electrónica , Enfermedades de las Aves de Corral/sangre , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/microbiología , Salmonella/aislamiento & purificación , Salmonelosis Animal/sangre , Salmonelosis Animal/inmunología , Salmonelosis Animal/microbiología , Pavos/microbiología
17.
Avian Dis ; 29(3): 617-29, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-4074235

RESUMEN

The effect of three treatments on Salmonella hadar infection in turkey poults was examined. The three treatments were: (A) a single injection of gentamicin, (B) peroral treatment with anaerobic culture derived from cecal contents of an adult turkey (Nurmi culture), and (C) combination of treatments A and B. Nurmi culture was significantly more effective than gentamicin treatment. Nurmi culture along with gentamicin reduced the number of shedding birds, but a higher proportion of birds became carriers compared with the groups given Nurmi culture only. Gentamicin injection alone did not prevent the spreading of infection in larger groups raised on litter, but it did so in one experimental group raised on wire floor.


Asunto(s)
Gentamicinas/uso terapéutico , Enfermedades de las Aves de Corral/terapia , Salmonelosis Animal/terapia , Animales , Enterobacteriaceae/inmunología , Inmunoterapia , Intestinos/microbiología
18.
Avian Dis ; 30(4): 794-801, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3028358

RESUMEN

From 1980 to 1984, several flocks of turkeys in Minnesota exhibiting signs of clinical enteritis were examined for viruses. Electron microscopic (EM) examination of fecal specimens from 35 flocks revealed the presence of rotavirus particles. Rotaviruses were successfully isolated in cell cultures from only 24 of these positive fecal specimens. Double-stranded RNA (dsRNA) preparations made from these 24 cell-culture isolates and from the remaining 11 fecal samples that were rotavirus-positive on EM examination were analyzed by polyacrylamide gel electrophoresis for genetic differences in their genomes. The study revealed eight distinct electropherotypes among the rotavirus dsRNA preparations. Atypical dsRNA migration patterns were recognized only in preparations of dsRNA from fecal materials.


Asunto(s)
ARN Bicatenario/análisis , ARN Viral/análisis , Rotavirus/análisis , Pavos/microbiología , Animales , Electroforesis en Gel de Poliacrilamida , Genes Virales , Rotavirus/genética , Rotavirus/aislamiento & purificación
19.
Avian Dis ; 30(3): 494-9, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3021099

RESUMEN

Avian rotaviruses were isolated from turkeys with enteritis using MA 104 cell line. MA 104 cells were suitable for primary isolation and propagation of avian rotaviruses. Trypsin appeared essential for the enhancement of infectivity and the occurrence of cytopathic effect (CPE). Serum neutralization (SN), electron microscopy (EM), and analysis of genomic RNA were done to identify and confirm the identity of rotaviruses. Electrophoretic migration patterns of genomic RNA from avian rotaviruses were examined, and they were compared with those from mammalian rotaviruses. The migration patterns differed between these groups.


Asunto(s)
Enteritis/veterinaria , Enfermedades de las Aves de Corral/microbiología , Infecciones por Rotavirus/veterinaria , Rotavirus/aislamiento & purificación , Pavos/microbiología , Animales , Línea Celular , Efecto Citopatogénico Viral , Enteritis/microbiología , ARN Viral/análisis , Rotavirus/análisis , Infecciones por Rotavirus/microbiología
20.
Avian Dis ; 30(2): 358-61, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3729881

RESUMEN

A phage-typing system for Salmonella hadar was developed. Fifteen phages isolated from untreated sewage were used to phage-type 55 isolates of S. hadar recovered from avian and other animal species. Twenty-four distinct phage types of S. hadar were established based on lysis patterns. Methods involved in the isolation for bacteriophages for a particular serotype and the importance of bacteriophage typing is discussed in the context of the importance of S. hadar.


Asunto(s)
Tipificación de Bacteriófagos , Aves de Corral/microbiología , Fagos de Salmonella/clasificación , Animales , Pollos/microbiología , Pavos/microbiología
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