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development and validation of a house finch interleukin-1β (hfil-1β) elisa system.a unique clade of the bacterium mycoplasma gallisepticum (mg), which causes chronic respiratory disease in poultry, has resulted in annual epidemics of conjunctivitis in north american house finches since the 1990s. currently, few immunological tools have been validated for this songbird species. interleukin-1β (il-1β) is a prototypic multifunctional cytokine and can affect almost every cell type during mycoplasma infection. the overall goal of this study was to develop and validate a direct eli ...201728854912
transcriptional profiling of the chicken tracheal response to virulent mycoplasma gallisepticum strain rlow.mycoplasma gallisepticum, the primary etiologic agent of chronic respiratory disease (crd) in poultry, leads to prolonged recruitment and activation of inflammatory cells in the respiratory mucosa. this is consistent with the current model of immune dysregulation that ostensibly allows the organism to evade clearance mechanisms and establish chronic infection. to date, studies using qrt-pcr and microarrays have shown a significant transient up-regulation of cytokines and chemokines from tracheal ...201728739827
pharmacokinetic depletion phase of doxycycline in healthy and mycoplasma gallisepticum-infected chicken broilers after coadministration of enrofloxacin traces.the objective of this study was to investigate the influence of enrofloxacin (enr) traces on doxycycline (dc) pharmacokinetic depletion phase parameters in plasma and lungs of healthy and mycoplasma gallisepticum (mg)-infected chicken broilers. the multiple-dose oral administration of dc to chickens which were permanently exposed on enr traces significantly increased concentration of dc in plasma and lung. it also prolonged the dc elimination time in both healthy and infected animals after final ...201728675463
gga-mir-99a targets smarca5 to regulate mycoplasma gallisepticum (hs strain) infection by depressing cell proliferation in chicken.mycoplasma gallisepticum (mg), one of the primary etiological agents of poultry chronic respiratory disease, has caused significant economic losses worldwide, and increasing evidence has recently indicated that mirnas are involved in its microbial pathogenesis. gga-mir-99a, a member of the mir-99 family, plays an essential role in a variety of diseases. through mirna solexa sequencing, we previously found that gga-mir-99a is significantly down-regulated in the lungs of mg-infected chicken embryo ...201728652181
the pk-pd relationship and resistance development of danofloxacin against mycoplasma gallisepticum in an in vivo infection model.mycoplasma gallisepticum is the causative agent of chronic respiratory disease (crd), a prevalent disease of poultry, which is responsible for significant economic losses in farms. although several antimicrobial agents are currently recommended for the treatment and prevention of m. gallisepticum infections, investigations of m. gallisepticum have been hampered by their fastidious growth requirements and slow growth rate. as such, little work has been conducted concerning the pk/pd relationship ...201728611739
tlr2 mediates autophagy through erk signaling pathway in mycoplasma gallisepticum-infected raw264.7 cells.toll-like receptor 2 (tlr2) plays a crucial role in early innate immune response of host to various microorganisms. mycoplasma gallisepticum (mg) is one of the major pathogen that can cause chronic respiratory diseases in chickens, but the molecular mechanism of mg infection still remained unclear. in this study, we examined the typical hallmarks of autophagy and multiple signaling pathways by western blot, immunofluorescence microscopy and electron microscopy. the results indicated that infecti ...201728478286
identification of differentially expressed mirnas through high-throughput sequencing in the chicken lung in response to mycoplasma gallisepticum hs.mycoplasma gallisepticum (mg) infects chickens, causes chronic respiratory diseases (crd) and severely damages the poultry industry. it has been suggested that micro-ribonucleic acids (mirnas) are involved in microbial pathogenesis. here, we identified mirnas that are associated with mg infection in chicken lungs at 3 and 10days post-infection by deep sequencing. thirty-six down-regulated and 9 up-regulated mirnas belonging to 31 mirna families were detected at 3days post-infection, whereas 50 d ...201728433919
efficacy of tiamulin alone or in combination with chlortetracycline against experimental mycoplasma gallisepticum infection in chickens.mycoplasma gallisepticum (m. gallisepticum) remains one of the most important diseases in poultry production. controlling the impact of the disease is done by eradication of positive breeder flocks or by vaccination and medication. a widely used molecule in medication programs is tiamulin, a pleuromutilin antibiotic. since recent data on the in vivo efficacy of this molecule are scarce, 2 challenge studies were conducted using a recently isolated m. gallisepticum strain belonging to the wildtype ...201728431183
attenuated phenotype of a recent house finch-associated mycoplasma gallisepticum isolate for domestic poultry.mycoplasma gallisepticum, known primarily as a respiratory pathogen of domestic poultry, has emerged since 1994 as a significant pathogen of the house finch (haemorhous mexicanus) causing severe conjunctivitis and mortality. house finch-associated m. gallisepticum (hfmg) spread rapidly and increased in virulence for the finch host in the eastern united states. in the current study, we assessed virulence in domestic poultry with two temporally distant, yet geographically consistent, hfmg isolates ...201728396323
the oppd gene and putative peptidase genes may be required for virulence in mycoplasma gallisepticum.relatively few virulence genes have been identified in pathogenic mycoplasmas, so we used signature-tagged mutagenesis to identify mutants of the avian pathogen mycoplasma gallisepticum with reduced capacity to persist in vivo and compared the virulence of selected mutants in experimentally infected chickens. four mutants had insertions in one of the two incomplete oppabcdf operons and a further three had insertions in distinct hypothetical genes, two containing peptidase motifs and one a member ...201728348054
immune responses to vaccination and infection with mycoplasma gallisepticum in turkeys.infection with mycoplasma gallisepticum induces severe lymphoproliferative lesions in multiple sites along the respiratory tract in chickens and turkeys. these immunopathological responses have been well-characterised in chickens, but have not been studied closely in turkeys. the aim of the studies described here was to examine the immune responses of turkeys after live vaccination and infection with m. gallisepticum. in a strain comparison study, the mean log10 antibody titre of birds exposed t ...201728345962
serological screening suggests extensive presence of mycoplasma gallisepticum and mycoplasma synoviae in backyard chickens in southern mozambique.a total of 459 serum samples from unvaccinated backyard chickens originating from 4 villages in mandlakazi district, southern mozambique, were tested for the presence of mycoplasma gallisepticum and mycoplasma synoviae antibodies through commercial enzyme-linked immunoabsorbent assay [elisa] kits. anti-mg and anti-ms antibodies were detected in all villages surveyed and the overall seroprevalence was 48.8% [95% ci 39.1-57.8] and 84.5% [95% ci 76.8-90.4], respectively. the risk of being seroposit ...201728243629
identification of genes involved in mycoplasma gallisepticum biofilm formation using mini-tn4001-sgm transposon mutagenesis.mycoplasma gallisepticum (mg) is an important pathogen that can cause chronic respiratory disease in chickens and infectious sinusitis in turkeys. mg has the ability to form biofilms. the molecular mechanisms underlying mg biofilm formation are complex and poorly understood. to better understand the mechanisms involved in biofilm formation, mini-tn4001-sgm, a novel transposon vector containing the gentamicin gene was constructed and electroporated into mg strain rlow. of the 738 mutants obtained ...201728062003
determination of the mutant selection window and evaluation of the killing of mycoplasma gallisepticum by danofloxacin, doxycycline, tilmicosin, tylvalosin and valnemulin.mycoplasma gallisepticum is a common etiological cause of a chronic respiratory disease in chickens; its increasing antimicrobial resistance compromises the use of tetracyclines, macrolides and quinolones in the farm environment. mutant selection window (msw) determination was used to investigate the propensity for future resistance induction by danofloxacin, doxycycline, tilmicosin, tylvalosin and valnemulin. killing of m. gallisepticum strain s6 by these antimicrobials was also studied by incu ...201728052123
detection of infectious bronchitis virus 793b, avian metapneumovirus, mycoplasma gallisepticum and mycoplasma synoviae in poultry in ethiopia.a survey was conducted into respiratory infectious diseases of poultry on a chicken breeder farm run by the ethiopian institute of agricultural research (eiar), located in debre zeit, ethiopia. oropharyngeal swabs were collected from 117 randomly selected birds, and blood was taken from a subset of 73 of these birds. a combination of serological and molecular methods was used for detection of pathogens. for the first time in ethiopia, we report the detection of variant infectious bronchitis viru ...201727924415
the efficacy of chitosan-adjuvanted, mycoplasma gallisepticum bacterin in chickens.mycoplasma gallisepticum (mg) is one of the major pathogens that cause respiratory signs in the poultry industry. to control mg infection, vaccination is the useful procedure. in this study, mg vaccine was developed by using the local thai mg isolate (ahrl 20/52). chitosan, a polysaccharide adjuvant derived from crustaceans, has been successfully used in various vaccines. the objectives of this study were to prepare mg bacterins by using chitosan, serving as an adjuvant, to determine protection ...201627902896
phase transition of the bacterium upon invasion of a host cell as a mechanism of adaptation: a mycoplasma gallisepticum model.what strategies do bacteria employ for adaptation to their hosts and are these strategies different for varied hosts? to date, many studies on the interaction of the bacterium and its host have been published. however, global changes in the bacterial cell in the process of invasion and persistence, remain poorly understood. in this study, we demonstrated phase transition of the avian pathogen mycoplasma gallisepticum upon invasion of the various types of eukaryotic cells (human, chicken, and mou ...201627775027
egg quality in laying hens exposed to mycoplasma gallisepticum f-strain attenuated vaccine.mycoplasma gallisepticum causes coughing, ocular and nasal discharge, reduction in feed intake, lower and uneven growth, decline in egg production and quality, and increase in mortality. among the attenuated vaccination strains, mgf can reduce clinical signs and lesions in layer hens, stimulate immune responses of cellular and humoral basis, act as an instrument of competitive exclusion in relation to field strains, and reduce the use of antimicrobials. this study aimed to investigate the effect ...201627738118
chicken gga-mir-19a targets zmynd11 and plays an important role in host defense against mycoplasma gallisepticum (hs strain) infection.mycoplasma gallisepticum (mg), one of the most pathogenic mycoplasmas, can cause chronic respiratory disease (crd) in chickens. it has been suggested that micro-ribonucleic acids (mirnas) are involved in microbial pathogenesis. however, little is known about the roles of mirnas in mg infection. previously, we found by deep sequencing that gga-mir-19a was significantly up-regulated in the lungs of mg-infected chicken embryos. in this work, we confirmed that gga-mir-19a was up-regulated in both mg ...201727683641
pharmacokinetic/pharmacodynamic profiles of tiamulin in an experimental intratracheal infection model of mycoplasma gallisepticum.mycoplasma gallisepticum is the most important pathogen in poultry among four pathogenic mycoplasma species. tiamulin is a pleuromutilin antibiotic that shows a great activity against m. gallisepticum and has been approved for use in veterinary medicine particularly for poultry. however, the pharmacokinetic/pharmacodynamics (pk/pd) profiles of tiamulin against m. gallisepticum are not well understood. therefore, in the current studies, we investigated the in vivo pk/pd profiles of tiamulin using ...201627656647
mutations of domain v in 23s ribosomal rna of macrolide-resistant mycoplasma gallisepticum isolates in egypt.avian mycoplasmas impose a significant economic burden to the poultry industry. in recent years, macrolide-resistant mycoplasma gallisepticum have occasionally been encountered in egypt.201627580325
rapid and sensitive detection of mycoplasma synoviae by an insulated isothermal polymerase chain reaction-based assay on a field-deployable device.mycoplasma synoviae (ms), causing respiratory diseases, arthritis, and eggshell apex abnormalities in avian species, is an important pathogen in the poultry industry. implementation of a biosecurity plan is important in ms infection management. working on a field-deployable pockit™ device, an insulated isothermal polymerase chain reaction (iipcr) assay has a potential for timely ms detection on the farm. the ms iipcr assay had limit of detection 95% of about 9 genome equivalents by testing seria ...201727389062
the pk/pd interactions of doxycycline against mycoplasma gallisepticum.mycoplasma gallisepticum is one of the most important pathogens that cause chronic respiratory disease in chicken. this study investigated the antibacterial activity of doxycycline against m. gallisepticum strain s6. in static time-killing studies with constant antibiotic concentrations [0-64 minimum inhibitory concentration (mic)], m. gallisepticum colonies were quantified and kill rates were calculated to estimate the drug effect. the half-life of doxycycline in chicken was 6.51 ± 0.63 h. an i ...201627199972
mycoplasma gallisepticum modifies the pathogenesis of influenza a virus in the avian tracheal epithelium.multiple respiratory infections have a significant impact on health and economy. pathogenesis of co-infecting viruses and bacteria and their interaction with mucosal surfaces are poorly characterized. in this study we established a co-infection model based on pre-incubation of tracheal organ cultures (toc) with mycoplasma (m.) gallisepticum and a subsequent infection with avian influenza virus (aiv). mycoplasma gallisepticum modified the pathogenesis of aiv as demonstrated in toc of two differen ...201627079856
seroprevalence of mycoplasma gallisepticum antibody by elisa and serum plate agglutination test of laying chicken.mycoplasma gallisepticum (mg) is important avian pathogens responsible for chronic respiratory diseases of chicken and turkeys, which result in large economic loss for the poultry industry. the objectives of this study were determination of seroprevalence of mg antibody of commercial layer chicken at laying period in selected areas of bangladesh.201527046987
pathogenicity of mycoplasma imitans in mixed infection with infectious bronchitis virus in chickens.mycoplasma imitans (mim) has been isolated from ducks, geese and partridges, and is closely related to mycoplasma gallisepticum (mg). the pathogenicity of mim for chicks was investigated in single and mixed infections with infectious bronchitis virus (ibv) by giving ibv strain m41 at 1-day-old and mim 2 days later. single infections with ibv or mim were also performed. no clinical signs or gross lesions were seen in chicks infected with mim or uninfected control chicks, but they were seen in the ...199926915378
experiences with multispecies polymerase chain reaction and specific oligonucleotide probes for the detection of mycoplasma gallisepticum and mycoplasma synoviae.amplified fragments of the rdna coding for 16s rrna of mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) were blotted on nylon membranes, followed by dot-blot detection with two species-specific digoxigenin-(dig)-labeled oligonucleotide probes. the sensitivity and specifity of the tests were determined in titration studies with purified homologous and heterologous dna. with the detection protocol used, the msyv8/31 probe showed 100% specifity for ms, while both mg and the related specie ...199926905489
influence of enrofloxacin traces in drinking water to doxycycline tissue pharmacokinetics in healthy and infected by mycoplasma gallisepticum broiler chickens.most of antibiotics, administrated in the treatment of poultry diseases are dissolved in drinking water, and it can lead to water supply systems contamination, especially when the regular cleaning is not using. this situation can lead to unconscious administration of low doses of antibiotics to untreated animals. the aim of this study was to clarify the impact of the exposure of enrofloxacin traces (500 μg l(-1)) to doxycycline pharmacokinetics in healthy and experimentally mycoplasma gallisepti ...201626875641
roles of toll-like receptors 2 and 6 in the inflammatory response to mycoplasma gallisepticum infection in df-1 cells and in chicken embryos.while mycoplasma gallisepticum (mg) is a major pathogen that causes chronic respiratory diseases in chicken, the molecular mechanism of mg infection is not clear. in this study, we investigated the roles of toll-like receptor 2 (tlr2) and 6 (tlr6) in mg infection. we found that tlr2 type 2 (tlr2-2) and tlr6 had differential expressions in chicken embryo fibroblasts (df-1 cells), where tlr6 was highly expressed, but tlr2-2 was barely expressed. upon mg infection, tlr6 expression was upregulated, ...201626797426
gga-mir-101-3p plays a key role in mycoplasma gallisepticum (hs strain) infection of chicken.mycoplasma gallisepticum (mg), one of the most pathogenic mycoplasma, has caused tremendous economic loss in the poultry industry. recently, increasing evidence has suggested that micro ribonucleic acids (mirnas) are involved in microbial pathogenesis. however, little is known about potential roles of mirnas in mg infection of chicken. in the present study, using mirna solexa sequencing we have found that gga-mir-101-3p was up-regulated in the lungs of mg-infected chicken embryos. moreover, gga- ...201526633386
proteomic analysis of tylosin-resistant mycoplasma gallisepticum reveals enzymatic activities associated with resistance.mycoplasma gallisepticum is a significant pathogenic bacterium that infects poultry, causing chronic respiratory disease and sinusitis in chickens and turkeys, respectively. m. gallisepticum infection poses a substantial economic threat to the poultry industry, and this threat is made worse by the emergence of antibiotic-resistant strains. the mechanisms of resistance are often difficult to determine; for example, little is known about antibiotic resistance of m. gallisepticum at the proteome le ...201526584633
global changes in mycoplasma gallisepticum phase-variable lipoprotein gene vlha expression during in vivo infection of the natural chicken host.mycoplasma gallisepticum is the primary etiologic agent of chronic respiratory disease in poultry, a disease largely affecting the respiratory tract and causing significant economic losses worldwide. immunodominant proteins encoded by members of the variable lipoprotein and hemagglutinin (vlha) gene family are thought to be important for mechanisms of m. gallisepticum-host interaction, pathogenesis, and immune evasion, but their exact role and the overall nature of their phase variation are unkn ...201526553465
mycoplasma gallisepticum (hs strain) surface lipoprotein pmga interacts with host apolipoprotein a-i during infection in chicken.the adhesin protein from mycoplasma gallisepticum (hs strain), namely pmga1.2, is required for m. gallisepticum (mg) infection in chicken. however, the host factor(s) that interact with pmga1.2 is not known. in this study, we prepared the membrane fraction of trachea epithelial cells from chicken embryos. using an improved virus overlay protein blot assay (vopba) and glutathione s-transferase (gst) pull-down assay, we found that pmga1.2 specifically bound to a ∼30 kda host protein. this host pro ...201626549235
interaction of mycoplasma gallisepticum with chicken tracheal epithelial cells contributes to macrophage chemotaxis and activation.mycoplasma gallisepticum colonizes the chicken respiratory mucosa and mediates a severe inflammatory response hallmarked by subepithelial leukocyte infiltration. we recently reported that the interaction of m. gallisepticum with chicken tracheal epithelial cells (tecs) mediated the upregulation of chemokine and inflammatory cytokine genes in these cells (s. majumder, f. zappulla, and l. k. silbart, plos one 9:e112796, http://dx.doi.org/10.1371/journal.pone.0112796). the current study extends the ...201526527215
co-infection with multiple respiratory pathogens contributes to increased mortality rates in algerian poultry flocks.respiratory infections are a common cause for increased mortality rates in poultry worldwide. to improve intervention strategies, circulating pathogens have to be identified and further characterized. because of the lack of diagnostic tools, it was not known what pathogens contribute to the high mortality rates in association with respiratory disease in algeria. our objective was to determine if primary pathogens including mycoplasma gallisepticum (mg), mycoplasma synoviae (ms), avian influenza ...201526478165
isolation and molecular characterization of mycoplasma gallisepticum and mycoplasma synoviae in chickens in sudan.the current study described the isolation and molecular detection of mycoplasma gallisepticum (mg) and mycoplasma synoviae from tracheal swabs of diseased birds showing signs of respiratory distress in selected commercial (layer and broiler) farms and from yolk and an open air of pens of vaccinated breeder flocks in sudan. a number of 45 mycoplasma isolates were recovered from chickens in khartoum, gezira, and equatoria states in sudan. of these, eight mg and three ms isolates were identified us ...201326464902
expression and immunological characteristics of the surface-localized pyruvate kinase in mycoplasma gallisepticum.the widespread avian pathogen mycoplasma gallisepticum is a causative agent of respiratory disease. the wall-less prokaryotes lack some tricarboxylic acid cycle enzymes, therefore, the glycolysis metabolic pathway is of great importance to these organisms. pyruvate kinase (pk) is one of the key enzymes of the glycolytic pathway, and its immunological characteristics in mycoplasma are not well known. in this study, the m. gallisepticum pyruvate kinase fusion protein (pykf) was expressed in a pet ...201526456557
application of molecular and serological methods for rapid detection of mycoplasma gallisepticum infection (avian mycoplasmosis).mycoplasma infection is a major problem in veterinary medicine and in poultry production. the pathogen has many strains, so that diagnosis of the disease using culture method is not effective. the objective of this work was to evaluate the prevalence of mycoplasma gallisepticum (mg) in kuwait poultry farms using serology and molecular methods in comparison to the culture under specific conditions. a total of 50 swab samples from choanal cleft and tracheal samples and blood samples were obtained ...201526364358
effects of different vaccine combinations against mycoplasma gallisepticum on blood characteristics in commercial layer chickens.mycoplasma gallisepticum (mg) is a major and economically significant pathogen of avian species. when administered before lay, f-strain mg (fmg) can reduce egg production during lay, but the ts-11 strain of mg (ts11mg) does not exert this effect. two trials were conducted to determine the effects of pre-lay vaccinations of ts11mg, mg-bacterin (mgbac), or their combination, in conjunction with an fmg challenge overlay after peak production on the blood characteristics of commercial layers. in eac ...201526217033
a survey of mycoplasma gallisepticum and mycoplasma synovaie with avian influenza h9 subtype in meat-type chicken in jordan between 2011-2015.commercial chickens in jordan suffer from respiratory disease of undetermined etiology. this study was designed to document the involvement of avian influenza virus (aiv) h9 subtype, mycoplasma gallisepticum (mg), and mycoplasma synoviae (ms) in this respiratory disease. in this study, trachea swabs from 350 commercial broiler chicken flocks that suffered from respiratory disease were tested for aiv h9 subtype by using reverse transcription (rt)-pcr and for mg and ms by using pcr. pcr and rt-pcr ...201525971950
identification and functional characterization of toll-like receptor 2-1 in geese.toll-like receptor 2 (tlr2), an important pattern recognition receptor, activates proinflammatory pathways in response to various pathogens. it has been reported in humans and chicken, but not in geese, an important waterfowl species in china. since some vaccines stimulate robust immune responsesl in chicken but not in geeeses we speculated that their immune systems are different.201525967535
evaluation of the egg transmission and pathogenicity of mycoplasma gallisepticum isolates genotyped as ts-11.live mycoplasma gallisepticum vaccines are used for the control of respiratory disease, egg production losses and egg transmission associated with m. gallisepticum infection in long-lived poultry. the first field case of apparent increased virulence and vertical transmission of ts-11, a live m. gallisepticum vaccine, has been reported. in that study a m. gallisepticum isolate from the broiler progeny of ts-11-vaccinated breeders was genotyped as ts-11 by sequence analysis of four different genet ...201525925422
experimental pathology of t-2 toxicosis and mycoplasma infection on performance and hepatic functions of broiler chickens.this experiment was conducted using 192 day-old ross 308 chicks, divided into 4 groups of 4 replicate consisting 48 birds. group i was fed a control diet, group ii was fed control diet supplemented with 0.5 ppm t-2 toxin for 5 weeks, group iii was fed control diet supplemented with 8 × 10(8) cfu/ml of mycoplasma gallisepticum, and group iv was fed control diet supplemented by t-2 toxin and mycoplasma gallisepticum. body weight and feed conversation ratio (fcr), relative organ weights, clinical s ...201525910901
in vivo pharmacokinetic/pharmacodynamic profiles of valnemulin in an experimental intratracheal mycoplasma gallisepticum infection model.valnemulin, a semisynthetic pleuromutilin antibiotic derivative, is greatly active against mycoplasma. the objective of our study was to evaluate the effectiveness of valnemulin against mycoplasma gallisepticum in a neutropenic intratracheal model in chickens using a pharmacokinetic/pharmacodynamic (pk-pd) method. the pk of valnemulin after intramuscular (i.m.) administration at doses of 1, 10, and 20 mg/kg of body weight in m. gallisepticum-infected neutropenic chickens was evaluated by liquid ...201525845865
mycoplasma gallisepticum inactivated by targeting the hydrophobic domain of the membrane preserves surface lipoproteins and induces a strong immune response.an innovative approach for inactivation of mycoplasma gallisepticum using the hydrophobic photoinduced alkylating probe 1, 5-iodonaphthylazide (ina) is described. treatment of washed m. gallisepticum mid-exponential culture (0.2 mg cell protein /ml) with ina followed by irradiation with far-ultraviolet light (310-380 nm) completely abolished viability. transmission electron microscopy showed that the majority of the inactivated m. gallisepticum were comparable in size to intact cells, but that p ...201525781939
ex vivo pharmacokinetic and pharmacodynamic analysis of valnemulin against mycoplasma gallisepticum s6 in mycoplasma gallisepticum and escherichia coli co-infected chickens.pharmacokinetic and pharmacodynamic (pk/pd) indices against mycoplasma gallisepticum (mg) s6 were investigated in an ex vivo pk/pd model following oral administration of valnemulin to chickens co-infected with m. gallisepticum and escherichia coli. the minimum inhibitory concentrations (mics) for valnemulin against mg s6 in artificial medium and chicken serum were determined. in vitro time-killing curves were established according to a series of multiples of the mic value in an artificial medium ...201525744809
longitudinal monitoring for respiratory pathogens in broiler chickens reveals co-infection of chlamydia psittaci and ornithobacterium rhinotracheale.chlamydia psittaci is prevalent in broiler chicken production. however, the role of c. psittaci in the respiratory disease complex needs to be clarified. our aim was to identify the time point when a c. psittaci infection appeared on a broiler farm and to examine the presence of other respiratory pathogens at that time. we focused on the 'major' respiratory pathogens occurring in belgian broilers, namely infectious bronchitis virus (ibv), avian metapneumovirus (ampv), ornithobacterium rhinotrach ...201525724936
effects of different vaccine combinations against mycoplasma gallisepticum on the internal egg and eggshell characteristics of commercial layer chickens 1,2,3.live f-strain mycoplasma gallisepticum (fmg) vaccines are presently being used to help control field-strain mg outbreaks. however, they may exert some adverse effects on egg production. live strains of mg of lesser virulence as well as killed vaccines have little or no effect on egg production, but afford lower levels of protection. this has led to research investigating their use in combination with a subsequent overlay vaccination of fmg given later in the production cycle. in the present stud ...201525701207
cloning, expression, and antigenic characterization of recombinant protein of mycoplasma gallisepticum expressed in escherichia coli.mycoplasma gallisepticum (mg) is a member of the most important avian mycoplasmas, causing chronic respiratory disease in chickens and leading to important economic losses in the poultry industry. recombinant technology represents a strategic approach used to achieve highly reliable and specific diagnostic tests in veterinary diseases control: in particular this aspect is crucial for confirming mycoplasma infection and for maintaining mycoplasma-free breeder flocks. in this study, we identified ...201525667423
molecular detection of avian pathogens in poultry red mite (dermanyssus gallinae) collected in chicken farms.poultry red mite (prm, dermanyssus gallinae) is a blood-sucking ectoparasite as well as a possible vector of several avian pathogens. in this study, to define the role of prm in the prevalence of avian infectious agents, we used polymerase chain reaction (pcr) to check for the presence of seven pathogens: avipox virus (apv), fowl adenovirus (fadv), marek's disease virus (mdv), erysipelothrix rhusiopathiae (er), salmonella enterica (se), mycoplasma synoviae (ms) and mycoplasma gallisepticum (mg). ...201425649939
high seroprevalence of respiratory pathogens in hobby poultry.seroprevalence studies on respiratory pathogens have been done extensively in commercial laying hens, broilers, and, to a lesser extent, backyard poultry. in europe, seroprevalence studies in backyard and fancy breed poultry flocks are scarce and limited to a few pathogens, such as mycoplasma gallisepticum (mg); others, such as ornithobacterium rhinotracheale (ort), are missing. a commercial elisa for detection of antibodies against six selected pathogens was performed on 460 serum samples from ...201425619008
mycoplasma gallisepticum in vivo induced antigens expressed during infection in chickens.until now only a few genes encoding virulence factors have been characterized in the avian pathogen mycoplasma gallisepticum. in order to identify candidate targets associated with infection we applied an immunoscreening technique-in vivo induced antigen technology (iviat)-to detect immunogens of m. gallisepticum strain rlow expressed preferentially during in vivo infection. we identified 13 in vivo-induced (ivi) proteins that correspond to different functional categories including: previously r ...201525575879
the efficacy of mycoplasma gallisepticum k-strain live vaccine in broiler and layer chickens.the efficacy of a live mycoplasma gallisepticum (mg) vaccine candidate (k-strain) was compared to commercially available vaccines in broiler-type chickens (trial 1) and layer-type chickens (trial 2). in trial 1, three-week-old broiler-type chickens were vaccinated via aerosol with k-strain or an f-strain vaccine. the vaccinated chickens and 10 non-vaccinated controls were subsequently challenged with virulent r-strain via aerosol at six weeks post vaccination; both k-strain and f-strain vaccinat ...201525571953
development of a mycoplasma gallisepticum infection model in turkeys.mycoplasma gallisepticum causes chronic respiratory disease in chickens and is also highly pathogenic in turkeys. several live attenuated m. gallisepticum vaccines are available for prevention of disease in chickens but they are considered to be either not safe or not efficacious in turkeys. the studies presented here aimed to develop a suitable infection model in turkeys, a prerequisite for development of a vaccine against m. gallisepticum for turkeys. two wild-type australian m. gallisepticum ...201525431001
mycoplasma gallisepticum lipid associated membrane proteins up-regulate inflammatory genes in chicken tracheal epithelial cells via tlr-2 ligation through an nf-κb dependent pathway.mycoplasma gallisepticum-mediated respiratory inflammation in chickens is associated with accumulation of leukocytes in the tracheal submucosa. however the molecular mechanisms underpinning these changes have not been well described. we hypothesized that the initial inflammatory events are initiated upon ligation of mycoplasma lipid associated membrane proteins (lamp) to tlrs expressed on chicken tracheal epithelial cells (tec). to test this hypothesis, live bacteria or lamps isolated from a vir ...201425401327
mycoplasma gallisepticum mga_0676 is a membrane-associated cytotoxic nuclease with a staphylococcal nuclease region essential for nuclear translocation and apoptosis induction in chicken cells.mycoplasma gallisepticum can infect a wide variety of birds including the commercial poultry. m. gallisepticum mga_0676 is a putative lipoprotein, which is similar to bacterial thermostable nucleases. but the possible pathogenic effect of m. gallisepticum mga_0676 has not been investigated so far. in the present study, we cloned the mga_0676 gene after deletion of the amino-terminal signal sequence and mutagenesis of the mycoplasma tga tryptophan codons to tgg and expressed recombinant mga_0676 ...201525363559
pathomorphological studies of polyserositis in commercial caged layer chicken.to detect etiological agents and pathological changes associated with polyserositis in commercial layer chicken.201425312143
characterization of the chaperonin groel in mycoplasma gallisepticum.mycoplasma gallisepticum (mg) is a common and widespread cause of chronic respiratory disease in poultry. in this study, antigenic proteins were identified from mg membrane using two-dimensional gel electrophoresis (2-de) analysis followed by western blot and matrix-assisted desorption/ionization time-of-flight mass spectrometry (maldi-tof-ms), including translation elongation factor tu, dihydrolipoamide acetyltransferase (e2) component of pyruvate dehydrogenase complex, trigger factor, chaperon ...201525304689
hydrogen peroxide production from glycerol metabolism is dispensable for virulence of mycoplasma gallisepticum in the tracheas of chickens.hydrogen peroxide (h2o2) is a by-product of glycerol metabolism in mycoplasmas and has been shown to cause cytotoxicity for cocultured eukaryotic cells. there appears to be selective pressure for mycoplasmas to retain the genes needed for glycerol metabolism. this has generated interest and speculation as to their function during infection. however, the actual effects of glycerol metabolism and h2o2 production on virulence in vivo have never been assessed in any mycoplasma species. to this end, ...201425156740
simultaneous typing of nine avian respiratory pathogens using a novel gexp analyzer-based multiplex pcr assay.a new, rapid, and high-throughput genomelab gene expression profiler (gexp) analyzer-based multiplex pcr method was developed for simultaneous detection and differentiation of nine avian respiratory pathogens. the respiratory pathogens included in this study were avian influenza subtypes h5, h7, and h9, infectious bronchitis virus (ibv), newcastle disease virus (ndv), infectious laryngotracheitis virus (iltv), mycoplasma gallisepticum (mg), mycoplasma synoviae (ms) and haemophilus paragallinarum ...201425025815
effects of live and killed vaccines against mycoplasma gallisepticum on the performance characteristics of commercial layer chickens.different vaccine strains of mycoplasma gallisepticum have been used on multiple-age commercial layer farms in an effort to protect birds against virulent field-strain infections. use of the f-strain of m. gallisepticum (fmg), as an overlay vaccine during lay, may be necessary because of the lower level of protection afforded by m. gallisepticum vaccines of low virulence given before lay. two replicate trials were conducted to investigate effects of live and killed m. gallisepticum vaccines admi ...201424879690
effects of mycoplasma gallisepticum vaccination on serum α1-acid glycoprotein concentrations in commercial layer chickens.increases in circulating acute phase protein (app) levels occur in reaction to systemic infections in animals. however, no previous research has been conducted to monitor possible changes in app levels of birds in response to prelay vaccinations of various live attenuated mycoplasma gallisepticum vaccines in conjunction with their subsequent use as an overlay vaccine during the production period. serum concentrations of the app, α1-acid glycoprotein (agp), were determined on d 0, 1, 3, 7, 14, an ...201424879689
sequencing analysis of mycoplasma gallisepticum wild strains in vaccinated chicken breeder flocks.mycoplasma gallisepticum (mg) infection is still of continuing economic concern in commercial broiler breeder chicken flocks in egypt. mg infection continues to emerge despite the application of vaccination programs in breeder flocks. this prompted flock surveillance including mg isolation and molecular characterization of the circulating mg strains. the present study was concerned with 15 broiler breeder flocks of different ages (5-51 weeks). three flocks were apparently healthy and 12 flocks w ...201424525899
prevalence and differentiation of diseases in maryland backyard flocks.several epidemiologic surveillance studies have implicated backyard flocks as a reservoir for poultry diseases; however, much debate still exists over the risk these small flocks pose. to evaluate this concern, the prevalence of newcastle disease (nd), infectious laryngotracheitis (ilt), mycoplasma gallisepticum (mg), and salmonella was determined in 39 maryland backyard flocks. serum, tracheal, and cloacal swabs were randomly collected from 262 birds throughout nine counties in maryland. throug ...201324283123
impact of fowlpox-vectored mycoplasma gallisepticum vaccine vectormune fp mg on layer hen egg production and egg quality parameters.this study was conducted to determine the impact of vaccination with vectormune fp mg on egg production and egg quality characteristics of single comb white leghorn hens. due to questions of the efficacy of this vaccine in preventing mycoplasma gallisepticum-mediated pathology, the ability of this vaccine to protect against postproduction-peak egg losses associated with f-strain m. gallisepticum (fmg) vaccination was also investigated. vaccination with vectormune fp mg did not result in any sign ...201324235227
modelling of control options for an outbreak of mycoplasma gallisepticum in egg production: a decision support tool.mycoplasma gallisepticum (mg) is a bacterium that causes respiratory disease in chickens, leading to reduced egg production. a dynamic simulation model was developed that can be used to assess the costs and benefits of control using antimicrobials or vaccination in caged or free range systems. the intended users are veterinarians and egg producers. a user interface is provided for input of flock specific parameters. the economic consequence of an mg outbreak is expressed as a reduction in expect ...201324206630
factors influencing the cell adhesion and invasion capacity of mycoplasma gallisepticum.the cell invasiveness of mycoplasma gallisepticum, the causative agent of respiratory disease in chickens and infectious sinusitis in turkeys, may be a substantial factor in the well-known chronicity of these diseases and in the systemic spread of infection. to date, not much is known about the host factors and mechanisms involved in promotion or obstruction of m. gallisepticum adherence and/or cell invasion.in the current study, the influence of extracellular matrix (ecm) proteins such as fibro ...201324011130
decay of maternal antibodies in broiler chickens.the objective of this study was to determine the decay rate of maternal antibodies against major broiler chicken pathogens. a total of 30 one-day-old broiler chicks were obtained from a commercial hatchery and reared in isolation. these chicks were retrieved from a parent flock that received a routine vaccination program. chicks were bled at hatch and sequentially thereafter every 5 d through 30 d of age. maternal antibody titers were measured by elisa for avian encephalomyelitis (aev), avian in ...201323960115
mycoplasma gallisepticum and escherichia coli mixed infection model in broiler chickens for studying valnemulin pharmacokinetics.a mycoplasma gallisepticum-escherichia coli mixed infection model was developed in broiler chickens, which was applied to pharmacokinetics of valnemulin in the present experiment. the velogenic m. gallisepticum standard strain s6 was rejuvenated to establish the animal model, and the wild e. coli strain o78 was injected as supplementary inoculum to induce chronic respiratory disease in chickens. the disease model was evaluated based on its clinical signs, histopathological examination, bacteriol ...201423782411
influences of f-strain mycoplasma gallisepticum vaccine on productive and reproductive performance of commercial parent broiler chicken breeders on a multi-age farm.the influences of f-strain mycoplasma gallisepticum (fmg) vaccine inoculation during the pullet period on the subsequent productive and reproductive performance of parent broiler chicken breeders on a multi-age farm were evaluated. three thousand breeders were randomly divided into 2 treatment groups that were either vaccinated with fmg (fmg-vaccinated group) or not vaccinated with fmg (fmg-free group). body weight and egg production were determined through approximately 50 wk of age. egg weight ...201323687149
malf is essential for persistence of mycoplasma gallisepticum in vivo.there is limited understanding of the molecular basis of virulence in the important avian pathogen mycoplasma gallisepticum. to define genes that may be involved in colonization of chickens, a collection of mutants of the virulent ap3as strain of m. gallisepticum were generated by signature-tagged transposon mutagenesis. the collection included mutants with single insertions in the genes encoding the adhesin gapa and the cytadherence-related protein crma, and western blotting confirmed that thes ...201323657682
plasma and tissue pharmacokinetics of marbofloxacin in experimentally infected chickens with mycoplasma gallisepticum and escherichia coli.the plasma and tissue pharmacokinetics of marbofloxacin in chickens experimentally infected with mycoplasma gallisepticum and escherichia coli were studied. marbofloxacin was given to 66 infected chickens by oral administration at a dosage of 5 mg/kg b.w., once a day for three days. plasma, brain, kidney, liver, lung, muscle and trachea were collected and marbofloxacin concentrations were analyzed by a high performance liquid chromatography method. in the infected chickens, maximal marbofloxacin ...201323550715
experimental induction and oral transmission of avian aa amyloidosis in vaccinated white hens.avian aa amyloidosis is commonly observed in adult birds afflicted with bacterial infections or chronic inflammatory disorders. experimental aa amyloidosis in birds can be induced by repeated inflammatory stimulation, such as injection with casein or vaccination with oil-emulsified bacterins. however, the transmission of amyloidosis among avian species has not been studied well to date. in the present study, we confirm the potential induction of avian aa amyloidosis by inoculation of salmonella ...201323548152
serologic, parasitic, and bacteriologic assessment of captive cracids (aves: galliformes: cracidae) in brazil.captive cracids (aves: galliformes: cracidae), including endangered species, were studied (n = 130) for the assessment of health status, including aburria jacutinga (black-fronted piping-guan, n = 42), crax blumenbachii (red-knobbed curassow, n = 54), craxfasciolata (bare-faced curassow, n = 28), and penelope obscura (dusky-legged guan, n = 6). the exposure to mycoplasma gallisepticum (mg), mycoplasma synoviae (ms), salmonella pullorum (sp), salmonella gallinarum (sg), avian paramyxovirus-1 (apm ...201323505700
role of the gapa and crma cytadhesins of mycoplasma gallisepticum in promoting virulence and host colonization.mycoplasma gallisepticum is an important avian pathogen that commonly induces chronic respiratory disease in chicken. to better understand the mycoplasma factors involved in host colonization, chickens were infected via aerosol with two hemadsorption-negative (ha(-)) mutants, mhad3 and rcl2, that were derived from a low passage of the pathogenic strain r (rlow) and are both deficient in the two major cytadhesins gapa and crma. after 9 days of infection, chickens were monitored for air sac lesion ...201323460514
effect of infection route and concurrent infectious bronchitis virus vaccination on mycoplasma gallisepticum disease pathology in an experimental model.the study of mycoplasma gallisepticum (mg) infection is needed, not only to understand the disease process but also to understand the mechanisms by which mg vaccines protect the host. many model systems have been used to study the mg disease process. this work compared two different routes of infection (intratracheal versus eye drop) in commercial pullets, looking for differences in the pathology (air sac and tracheal lesion scores, and tracheal mucosal thickness) and the humoral immune response ...201223025670
influence of swab material on the detection of mycoplasma gallisepticum and mycoplasma synoviae by real-time pcr.recent reports have shown an increased recovery of cells from flocked nylon swabs which may improve the specimen quality and the real sensitivity of diagnostic tests in a clinical setting. in this study, the detection of mycoplasma gallisepticum (mg) and m. synoviae (ms), using dry swabs of different materials (nylon flocked, cotton, and polyester), was investigated using real-time taqman pcr protocols. different types of samples, including dilutions of pure broth cultures of mg and ms as well a ...201222856187
the efficacy of three commercial mycoplasma gallisepticum vaccines in laying hens.the efficacy of three commercial mycoplasma gallisepticum (mg) immunizing agents-a bacterin, a recombinant fowlpox-mg vaccine, and a live f-strain vaccine-was compared in specific-pathogen-free hens in egg production. three groups of 25 chickens were vaccinated with one of the vaccines at 10 wk of age and 25 birds were not vaccinated. at 25 wk of age (and approximately 50% egg production), 20 birds from each of the three vaccinated groups and 15 nonvaccinated controls were challenged with virule ...201222856181
effect of low-pathogenicity influenza virus h3n8 infection on mycoplasma gallisepticum infection of chickens.mycoplasma infection is still very common in chicken and turkey flocks. several low-pathogenicity avian influenza (lpai) viruses are circulating in wild birds that can be easily transmitted to poultry flocks. however, the effect of lpai on mycoplasma infection is not well understood. the aim of the present study was to investigate the infection of lpai virus h3n8 (a/mallard/hungary/19616/07) in chickens challenged with mycoplasma gallisepticum. two groups of chickens were aerosol challenged with ...201222845321
identification of biofilm formation by mycoplasma gallisepticum.mycoplasma gallisepticum is the causative agent of chronic respiratory disease in chickens and of infectious sinusitis in turkeys, chickens, game birds, pigeons, and passerine birds of all ages. this study investigated the biofilm-producing ability of m. gallisepticum strains in an attempt to explain its intriguing persistence in commercial flocks. eleven strains of m. gallisepticum were investigated for their biofilm formation, which varied considerably. strains nobilis mg 6/85, s(6) (p(5) and ...201222840542
evaluation of mycoplasma gallisepticum k-strain as a live vaccine in chickens.we evaluated the pathogenicity of three live mycoplasma gallisepticum (mg) vaccine candidates by infection via aerosol of 3-wk-old chickens with log phase broth cultures (trial 1). two of the candidates (k3020 and k4649a) colonized only 10% and 20% of the chickens, respectively, unlike k2101 (k-strain), which was reisolated from all of the vaccinated chickens tested. k-strain inoculation did not result in significant air sac or tracheal lesions in chickens at 10 and 39 days postinfection (p < or ...201222545527
seroprevalence of newcastle disease and other infectious diseases in backyard chickens at markets in eastern shewa zone, ethiopia.this study was conducted to estimate the seroprevalence of newcastle disease (nd), pasteurella multocida (pm) infection, mycoplasma gallisepticum (mg) infection, and infectious bursal disease (ibd) and to assess the level of concurrent seropositivity during the dry and wet seasons of the year 2010. in total, 234 and 216 sera were collected during the dry and wet seasons, respectively, from unvaccinated backyard chickens at 4 live poultry markets in 2 woredas (districts) of eastern shewa zone, et ...201222399725
characterization of a ts-1-like mycoplasma galisepticum isolate from commercial broiler chickens.several commercial broiler flocks in northeastern georgia that were the progeny of the same parent flock (flock 40) were diagnosed as mycoplasma gallisepticum (mg) positive by serology, culture, and pcr. flock 40 had been vaccinated with ts-11 live mg vaccine. several isolates were obtained from the mg-positive broiler flocks, and these isolates were indistinguishable from the ts-11 vaccine strain by the molecular strain differentiation methods used. a pathogenicity study was performed to compar ...201122312975
Effects of sialidase knockout and complementation on virulence of Mycoplasma gallisepticum.Reannotation of the pathogenic Mycoplasma gallisepticum strain R(low) genome identified the hypothetical gene MGA_0329 as a homolog of the sialidase gene MS53_0199 of Mycoplasma synoviae strain MS53. Potent sialidase activity was subsequently quantitated in several M. gallisepticum strains. Because sialidase activity levels correlate significantly with differing M. synoviae strain virulence, we hypothesized this enzyme may also influence the virulence of M. gallisepticum. MGA_0329 was disrupted ...201122197303
preliminary clinical pharmacological investigations of tylosin and tiamulin in chickens.summary the minimal inhibitory concentrations (m1c) of tiamulin and tylosin for mycoplasma. gram-positive, and gram-negative micro-organisms isolated from chickens were determinated by the agar dilution method. median m1c values for tiamulin against mycoplasma gallisepticum (0.05 µg/ml) and mycoplasma synoviae (0.10 µg/ml) were 2 to 4 times lower than the corresponding values for tylosin. tiamulin was also slightly more effective in vitro in inhibiting escherichia coli, pasteurella multocida, ...198022039981
haemadsorption inhibition test for the identification of mycoplasma gallisepticum and mycoplasma synoviae.summary colonies of the avian mycoplasma strains mycoplasma gallisepticum s6 and mycoplasma synoviae wvu 1853 and two mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. three mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. the haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. no cross-inhibition ...197922039774
pathologic lesions caused by coinfection of mycoplasma gallisepticum and h3n8 low pathogenic avian influenza virus in chickens.chickens were infected under experimental conditions with mycoplasma gallisepticum and low pathogenic avian influenza (lpai) strain a/mallard/hungary/19616/07 (h3n8). two groups of chickens were aerosol challenged with m. gallisepticum strain 1226. seven days later, one of these groups and one mycoplasma-free group was challenged with lpai h3n8 virus; one group without challenge remained as negative control. eight days later, the birds were euthanized and examined for gross pathologic and histol ...201121825309
mycoplasma gallisepticum experimental infection and tissue distribution in chickens, sparrows and pigeons.the most effective approaches to control the spread of mycoplasma gallisepticum include strict biosecurity measures, continuous surveillance and eradication of infected flocks. the rapid expansion of the poultry industry worldwide in restricted geographical areas and severe economic losses due to m. gallisepticum outbreaks make it crucial to identify and better control the vectors responsible for the transmission of the disease. in the present study we evaluated the susceptibility of sparrows an ...201121812712
molecular characterization of mycoplasma gallisepticum isolates from jordan.two groups of mycoplasma gallisepticum (mg) isolates (n = 24) from jordan were analyzed by molecular methods and compared with other middle eastern isolates, related international isolates, and reference strains. the first group (n = 19) was isolated from july 2004 to january 2005 (isolation period a), and the newer group (n = 5) from june 2007 to april 2008 (isolation period b). the groups of isolates are from chicken flocks from northern jordan, but are not from the same farms. none of the flo ...201121793435
local immunity of the respiratory mucosal system in chickens and turkeys.this review article presents fundamental mechanisms of the local mucosal immunity in selected regions of the respiratory tract in healthy birds and in some pathological conditions. the respiratory system, whose mucosa come into direct contact with microorganisms contaminating inhaled air, has some associated structures, such as harderian gland (hg), conjunctive-associated lymphoid tissue (calt) and paranasal glands (pg), whose participation in local mechanisms of the mucosal immunity has been co ...201121721419
neuraminidase of mycoplasma synoviae desialylates heavy chain of the chicken immunoglobulin g and glycoproteins of chicken tracheal mucus.major poultry pathogens, mycoplasma gallisepticum and mycoplasma synoviae share several genes, including nanh that encodes their sialidases (neuraminidases). previous studies have shown considerable differences in neuraminidase enzymatic activity (neac) in m. synoviae strains and neac absence in individual cultures of two strains, ulb 925 and ulb 9122. the present study shows that the cultures lacking neac did not express nanh neuraminidase detectable by specific antibodies. in cultures of m. sy ...201121711189
the mycoplasma gallisepticum α-enolase is cell surface-exposed and mediates adherence by binding to chicken plasminogen.the α-enolase protein is reported to be an adhesin in several pathogenic bacterial species, but its role in mycoplasma gallisepticum is unknown. in this study, the m. gallisepticum α-enolase gene was adapted to heterologous expression in escherichia coli by performing overlapping polymerase chain reaction with site-directed mutagenesis to introduce a960g and a1158g mutations in the nucleotide sequence. the full-length mutated gene was cloned into a pgem-t easy vector and subcloned into the ex ...201121664449
biological characterization of russian mycoplasma gallisepticum field isolates.an earlier study on commercial chickens and turkeys with a history of respiratory disease established mycoplasma gallisepticum infection rates on 164 poultry farms of the russian federation. forty-seven (29%) of these poultry farms were m. gallisepticum-positive by polymerase chain reaction but isolation of the mycoplasma was successful only on 10 farms. five field isolates from different farms were selected for pathogenicity studies in specific pathogen-free chicks. clinical signs, seroconversi ...201121500042
seroprevalence of salmonella and mycoplasma infection in backyard chickens in the state of entre rios in argentina.the present work was conducted to study the seroprevalence of salmonella, mycoplasma gallisepticum (mg), and mycoplasma synoviae (ms) infection in backyard chickens located in entre ríos, argentina, over 3 periods of time. a total of 2,441 sera samples were collected from backyard chickens belonging to 256 family farms in 16 counties in the state of entre ríos from january to may 2003 (first period), december 2004 to april 2005 (second period), and october 2006 to may 2007 (third period). the pr ...201121406358
change in antimicrobial susceptibility of mycoplasma gallisepticum field isolates.this study compares the antimicrobial susceptibility over time between two groups of mycoplasma gallisepticum (mg) isolates from the same geographical area. minimum inhibitory concentration of 13 antimicrobials was determined against two groups of mg isolates from chickens. group 1 strains (n=22) were isolated in 2004-2005 while group 2 strains (n=7) were isolated in 2007-2008. minimum inhibitory concentration 50 for group 1 versus group 2 was 4/4, 0.5/0.5, ôëñ 0.031/ôëñ 64, ôëñ 0.031/2, ôëñ 0.0 ...201121382675
development and immunogenicity of recombinant gapa(+) mycoplasma gallisepticum vaccine strain ts-11 expressing infectious bronchitis virus-s1 glycoprotein and chicken interleukin-6.mycoplasma gallisepticum (mg) is a major pathogen of poultry that causes chronic respiratory disease in chickens and infectious sinusitis in turkeys. a live attenuated vaccine, ts-11, has been used for the control of mg in several countries. the efficacy of this vaccine is highly dose dependent and the flock antibody response is weak. to improve the functionality of the vaccine and investigate its potential as a delivery vector for foreign antigens and immunomodulatory proteins, we developed a d ...201121354248
analysis of the 16s to 23s rrna intergenic spacer region of mycoplasma synoviae field strains.mycoplasma synoviae has been associated with economic loss in the chicken and turkey industries. the molecular characterization of m. synoviae at strain level allows the analysis of relationships between strains that may be valuable in epidemiological investigations. in the present study, the intergenic spacer region (isr) between the 16s and 23s rrna genes was examined to see whether useful information about strains could be derived. m. synoviae has two copies of this region, which may not be e ...201121331951
eye surface area and dosage rates for spray vaccination.spray application of mycoplasma gallisepticum (mg) vaccines is a labor- and time-saving means of mass vaccination of layer chickens. recent assessment of spray characteristics of nozzles commonly used to apply mg vaccine in layer chicken operations has shown that the amount of respirable droplets (< 5 microm) is negligible. topical application of vaccine onto the eye surface has been suggested as a route of vaccination, but no estimates of vaccine load delivered via spray application were found ...201021313856
gapa+ mycoplasma gallisepticum ts-11 has improved vaccine characteristics.mycoplasma gallisepticum (mg) is an important poultry pathogen that causes respiratory disease and loss of production worldwide, and is currently controlled with live attenuated vaccines. these vaccines have limitations as they vary in their pathogenicity, the protection afforded and their transmissibility, but have been shown to effectively reduce losses associated with challenge in the field. a live attenuated vaccine, ts-11, has been used for the control of m. gallisepticum in several countri ...201121310786
effects of single and combined mycoplasma gallisepticum vaccinations on blood electrolytes and acid-base balance in commercial egg-laying hens.a previous study from our laboratory on f-strain mycoplasma gallisepticum-inoculated layers showed a significant increase in arterial partial pressure of oxygen (po(2)), which is generally associated with an oxygen-dependent improvement in tissue oxygenation. the aim of this study was to determine whether a killed (bacterin) and live ts-11-strain m. gallisepticum (ts-11-mg) vaccine treatment combination could further enhance the arterial po(2) levels in layer chickens. the experiment was conduct ...201121248332
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