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mycoplasma gallisepticum species and strain-specific recombinant dna probes.genomic libraries of vaccine (f-k810) and wild type (s6) mycoplasma gallisepticum were constructed in escherichia coli (strain jm83) using the plasmid vector puc8. recombinant clones were screened by colony, dot and southern hybridisations using 32p-labelled genomic dna from m. gallisepticum strains k810 and s6. eight clones were identified which contained dna sequences specific to m. gallisepticum and one clone was identified which contained a dna fragment unique to the vaccine strain (f-k810) ...198918679844
evaluation of two commercial enzyme-linked immunosorbent assay kits for the detection of mycoplasma gallisepticum antibodies.sensitivity and specificity of two commercial mycoplasma gallisepticum (mg) enzyme-linked immunosorbent assay (elisa) kits, rapid slide agglutination (sa) and haemagglutination inhibition (hi) tests were compared using sera from specific pathogen free chickens, turkeys or ducks which had been inoculated with various avian mycoplasmas, bacteria or with a reovirus. results show that sensitivity of sa was superior to elisa and hi tests in the ability to detect antibodies formed in early response to ...199418671097
investigations into the survival of mycoplasma gallisepticum, mycoplasma synoviae and mycoplasma iowae on materials found in the poultry house environment.following preliminary experiments to determine suitable methods for studying mycoplasma survival, suspensions of mycoplasma gallisepticum (four strains), mycoplasma synoviae (two strains) or mycoplasma iowae (two strains) were seeded onto replicate samples of cotton, rubber, straw, shavings, timber, food, feathers and human hair. the organisms were also seeded onto human skin, ear and nasal mucosa. all samples were cultured for viability after 4, 8, 12 and 24 h, and then daily up to 6 days. the ...199418671077
in vitro evaluation of various antimicrobials against mycoplasma gallisepticum and mycoplasma synoviae by the micro-broth method, and comparison with a commercially-prepared test system.the efficacy of danofloxacin, a new quinolone antimicrobial agent, was tested in vitro by the micro-broth method with nine field strains of mycoplasma gallisepticum (mg) and eight of m. synoviae (ms) and comparison was made with oxytetracycline and tylosin tartrate. the virulent s6 strain of mg was also included for reference. all mycoplasma strains, including a strain of mg that was resistant to tylosin tartrate, were susceptible to danofloxacin with minimal inhibitory concentrations ranging fr ...199418671075
variable expression of epitopes on the surface of mycoplasma gallisepticum demonstrated with monoclonal antibodies.twelve monoclonal antibodies (mabs) against mycoplasma gallisepticum (mg) strains f, r, s6(208) and pet2 were used for analysis of epitopes of 22 mg strains. six mabs recognized surface epitopes in the majority of strains, but did not react with variant strains like k 503 and k 703. two mabs reacted with epitopes on about 56 kilodalton (kda) proteins and showing consistent expression on mg colonies. three mabs recognized three different variable surface epitopes associated with about 67 kda prot ...199418671069
the polymerase chain reaction for mycoplasma gallisepticum detection.on the basis of the aligned 16s rrna sequences of mollicutes, a pair of primers was chosen for the detection of mycoplasma gallisepticum. when used in the polymerase chain reaction (pcr), the primers detected a specific amplification of all mg strains tested, yielding an expected 330 bp product. amplification was not detected when other mollicutes or e. coli were used as pcr templates. spf chickens were experimentally inoculated with two strains of m. gallisepticum or mycoplasma iowae. tracheal ...199318671058
indirect elisa for the detection of a specific antibody response against mycoplasma gallisepticum.an indirect enzyme-linked immunosorbent assay (elisa) was developed for determining mycoplasma gallisepticum antibodies in chicken sera. the m. gallisepticum antigen was detergent extracted and incorporated into iscoms. sediment of broth medium treated with sarcosyl was used as control antigen. sera were tested before and after absorption with broth medium components and elisa titres are expressed as optical density (od) at 492 nm. sera from experimentally or naturally infected chickens, those v ...199318671034
effect of duration of incubation of mycoplasma gallisepticum cultures on the sensitivity and specificity of antigens for elisa and microimmunofluorescence tests.in the production of mycoplasma gallisepticum (mg) antigens for elisa and microimmunofluorescence (mif) tests, two strains of mg, s6 and pg31, were grown in broth culture and harvested at intervals from 18 to 138 h. the effect of duration of incubation of culture on antigen sensitivity and specificity was assessed using homologous sera (against mg s6), and sera prepared against mycoplasma synoviae (ms), and against mycoplasma media. it was found, in both mg s6 and pg31 elisas, that in the period ...199318671032
exacerbation of mycoplasma gallisepticum infection in turkeys by rhinotracheitis virus.groups of 1-day-old turkey poults from a parent flock free of antibodies to turkey rhinotracheitis virus (trtv) and the pathogenic mycoplasmas, were infected by eyedrop with virulent trtv, with mycoplasma gallisepticum (mg) or with both agents together. dual infection resulted in increased morbidity compared with those groups given single infections. the presence of the mg in the dual infection had no apparent effect on the pathogenesis of the virus, but the virus caused the mycoplasma to be mor ...199218670941
use of polymerase chain reactions to detect mycoplasma gallisepticum, mycoplasma imitans, mycoplasma iowae, mycoplasma meleagridis and mycoplasma synoviae in birds of prey.certain mycoplasma spp. are pathogens of poultry, but little is known of the role of mycoplasmas in disease of birds of prey. species-specific polymerase chain reactions (pcrs) for the detection of the poultry pathogens mycoplasma gallisepticum, mycoplasma imitans, mycoplasma iowae, mycoplasma meleagridis and mycoplasma synoviae were therefore evaluated for use in birds of prey. the specificities of the pcr methods were established using avian and other mycoplasmas and also selected walled bacte ...200818661307
compatibility of a combination of tiamulin plus chlortetracycline with salinomycin in feed during a long-term co-administration in broilers.the pleuromutilin antibiotic tiamulin (tia) is known to produce a negative interaction in broilers when administered in combination with several ionophore anticoccidials such as salinomycin (sal). chlortetracycline (ctc), when administered simultaneously with tia, has demonstrated a synergistic antimicrobial effect. a 35-d feeding study was conducted in cages to evaluate the interaction effect of a combination of tia plus ctc at increasing inclusion levels when administered concurrently with sal ...200818648050
field evaluation of maternal antibody transfer to a group of pathogens in meat-type chickens.this study was conducted to evaluate the rate of antibody transfer on a flock basis from hens to their day-old chicks in meat-type chickens raised in a commercial setting. fifteen randomly selected hens from a commercial broiler-breeder flock were bled at 37, 40, and 45 wk of age. at day of bleeding, the collected eggs were identified and tracked through hatching where 30 hatchlings were randomly sampled and bled from the jugular vein. antibodies against 10 different pathogens were quantified fr ...200818648048
effect of selected water temperatures used in mycoplasma gallisepticum vaccine reconstitution on titer at selected time intervals.numerous methods are currently used throughout the poultry industry for the administration of vaccines. each utilizes water for vaccine reconstitution and/or administration, including two of the three commercially available live mycoplasma gallisepticum (mg) vaccines. selected water temperatures were used to reconstitute and/or dilute the three commercially available live mg vaccines. water temperatures included 4 c, 22 c (room temperature), and 32 c, and titer (color change units) was recorded ...200818646459
a recombinant antigen-based elisa for the simultaneous differential serodiagnosis of mycoplasma gallisepticum, mycoplasma synoviae, and mycoplasma meleagridis infections.we have previously identified species-specific dna fragments, referred to as ms2/28 and mm14, of mycoplasma synoviae and mycoplasma meleagridis, respectively. in the present study, we extended our analysis of the ms2/28 fragment that was found to encode a species-specific antigenic site, and we demonstrated the specificity of the mycoplasma gallisepticum hemagglutinin protein encoded by pmga1.2 (a member of the vlha gene family). then, we combined the escherichia coli-expressed products of ms2/2 ...200818646449
the influence of type of swab and laboratory method on the recovery of mycoplasma gallisepticum and mycoplasma synoviae in broth medium.swabs are often used to collect material for avian mycoplasma culture. such swabs, when inoculated into broth medium, are usually discarded prior to incubation of the broth. in this study the effect on growth of low numbers of mycoplasma gallisepticum and mycoplasma synoviae was compared in broths with and without retention of the swab. plain or charcoal cotton swabs on wooden or plastic sticks were more likely to give growth if retained in the medium for incubation, but rayon swabs on aluminium ...199518645826
ribotyping of mycoplasma gallisepticum strains with a 16s ribosomal rna gene probe.ribotyping with a 16s ribosomal rna gene (rdna) probe was applied to 25 mycoplasma gallisepticum strains composed of nine originally isolated in the us and uk, and 16 field isolates from japan. four distinct ribotypes were identified among the m. gallisepticum strains on the basis of sizes of the bands produced by digesting genomic dna with restriction enzymes hindiii, ecori, bglii and ecorv. three ribotypes were recognized among the 16 japanese isolates. the original and vaccine f strains were ...199518645820
the 64 kda lipoprotein of mycoplasma gallisepticum has two distinct epitopes responsible for haemagglutination and growth inhibition.a major mycoplasma gallisepticum polypeptide of 64 kda (p64) was characterized using two distinct monoclonal antibodies (mabs), mab ki produced in our laboratory and mab myg 001 produced by avakian & ley (1993). the p64 antigen was shown to be a lipoprotein in a radioimmunoprecipitation assay using [(3)h] palmitic acid-labelled m. gallisepticum cultures. the two mabs inhibited the growth of m. gallisepticum in liquid medium and reacted to two distinct epitopes on the same p64 antigen in competit ...199518645766
detection and quantification of mycoplasma gallisepticum genome load in conjunctival samples of experimentally infected house finches (carpodacus mexicanus) using real-time polymerase chain reaction.a taqman-based real-time, quantitative polymerase chain reaction (qpcr) assay utilizing the mgc2 gene was developed to detect mycoplasma gallisepticum in conjunctival swabs of experimentally infected house finches. the assay was demonstrated to be quantitative by the standard curve method with reproducible results within runs and between runs. the detection limit of the mgc2 assay was examined using two standards. the test had a detection limit of less than 14 copies per reaction when tested wit ...200818622854
effects of prelay ts11-strain mycoplasma gallisepticum inoculation and time-specific f-strain m. gallisepticum inoculation overlays on internal egg and eggshell characteristics of commercial laying hens.mycoplasma infections are pandemic in multiage layer chicken flocks, with mycoplasma gallisepticum being the species of greatest concern to commercial egg producers. live m. gallisepticum vaccines are presently being used to help control m. gallisepticum outbreaks. however, vaccination of layers with f-strain m. gallisepticum may adversely affect egg production. in the present study, 2 trials were conducted to compare the effects of 2 currently available live mycoplasma vaccines (the ts11- and f ...200818577616
pure: a webserver for the prediction of domains in unassigned regions in proteins.protein domains are the structural and functional units of proteins. the ability to parse proteins into different domains is important for effective classification, understanding of protein structure, function, and evolution and is hence biologically relevant. several computational methods are available to identify domains in the sequence. domain finding algorithms often employ stringent thresholds to recognize sequence domains. identification of additional domains can be tedious involving inten ...200818554415
in vitro susceptibilities to fluoroquinolones in current and archived mycoplasma gallisepticum and mycoplasma synoviae isolates from meat-type turkeys.monitoring of susceptibility to antibiotics in field isolates of pathogenic avian mycoplasmas is important for appropriate choice of treatment. our study compared in vitro susceptibility to enrofloxacin and difloxacin in recent (2005-2006) isolates of mycoplasma gallisepticum and mycoplasma synoviae from meat-type turkey flocks with archived (1997-2003) isolates and reference strains. comparison of minimal inhibitory concentration (mic) values determined by microtest, agar dilution and commercia ...200818534788
effects of a prelay 6/85-strain mycoplasma gallisepticum inoculation alone or in conjunction with subsequent f-strain m. gallisepticum inoculations during lay on the internal egg characteristics of commercial egg-laying hens.the effects of a prelay 6/85-strain mycoplasma gallisepticum (6/85 mg) inoculation alone or in conjunction with subsequent f-strain m. gallisepticum (fmg) inoculations during lay on the internal egg characteristics of commercial egg-laying hens were investigated. in the first 2 treatment groups, birds were sham inoculated or were inoculated with 6/85 mg at 10 wk of age. in a third treatment group, birds were inoculated with 6/85 mg at 10 wk in conjunction with a subsequent inoculation of fmg at ...200818493000
a comparison of a commercial pcr-based test to culture methods for detection of mycoplasma gallisepticum and mycoplasma synoviae in concurrently infected chickens.the suitability of commercial pcr-based test kits for the detection of either mycoplasma gallisepticum (mg) or m. synoviae (ms) was compared to detection by culture. the mg and ms kit detected six and five homologous strains respectively in broth cultures and there were no reactions with thirteen het-erologous species including m. imitans, a species phylogenetically closely related to mg. tracheal and lung/air-sac swabs were collected from twenty 17-week-old commercial pullets which were seropos ...199818484270
development of antibiotic resistance in mycoplasma gallisepticum in vitro.the results of in vitro tests for induction of antibiotic resistance in some strains of mycoplasma gallisepticum are reported. the number of passages required to induce resistance varied considerably between different antibiotics. in two groups of tests, with different strains of m. gallisepticum, resistance (>/= 1 mg/ml) to streptomycin appeared after two to three passages, to erythromycin and spiramycin after five to eight passages, to tylosin after nine to eleven and to enrofloxacin after eig ...199818484048
antibody response detected by immunoblot in respiratory tract washings of chickens after infection with mycoplasma gallisepticum.two experiments were conducted to test the sensitivity of western blotting for detection of m. gallisepticum antibodies in respiratory washings and sera of infected chickens by mouse monoclonal antibodies to chicken igg, igm and iga. in the first experiment, birds infected at 10 days of age were examined 2 weeks later. in the respiratory washings, iga antibodies reacted with eight polypeptides of m. gallisepticum, while igm and igg reacted with three. in the serum iga antibodies were not detecte ...199818484042
pathogenicity of mycoplasma gallisepticum and mycoplasma imitans in red-legged partridges (alectoris rufa).groups of 3-day-oid red-legged partridges were infected intranasally either with the s6 strain of m. gallisepticum or with an m. imitans strain from a partridge with sinusitis. starting 6-8 days post-infection (p.i.) birds in both groups developed signs of depression, nasal exudation, tracheal rales, sneezing, gasping, head shaking, watery eyes and eye scratching. the most outstanding feature was bilateral swelling of the infraorbital sinuses. morbidity reached 100% in the m. gallisepticum infec ...199818484030
lymphoproliferative responses of specific-pathogen-free chickens to mycoplasma gallisepticum strain pg31.mycoplasma gallisepticum (mg) is one of the aetiologic agents of chronic respiratory disease in chickens and infectious sinusitis in turkeys. we investigated humoral and cellular immune mechanisms following experimental infection with four different strains of mg. peripheral blood leukocytes (pbl) obtained from chickens were examined for proliferation using antigen preparations of whole cell mg as stimuli in vitro. a consistent lymphoproliferative response was observed against the homologous who ...199818483998
assessment of the efficacy of tilmicosin as a treatment for mycoplasma gallisepticum infections in chickens.this study involved two experiments which examined the efficacy of 'in water' tilmicosin medication for the treatment of experimental mycoplasma gallisepticum (mg) disease. the first experiment investigated tilmicosin concentrations of 50, 100, 200 and 400 mg/l administered for 5 days. in the second experiment, dose levels of 50, 75 and 100 mg/l tilmicosin administered for either 3 or 5 days were investigated. the first experiment suggested that tilmicosin was effective in reducing the incidence ...199818483985
pathogenicity of in vivo-passaged mycoplasma imitans in turkey poults in single infection and in dual infection with rhinotracheitis virus.mycoplasma imitans (mim) is a close relative of mycoplasma gallisepticum (mg), but has been isolated from ducks, geese and partridge. in order to investigate its potential pathogenicity for turkeys a uk isolate of mim from a partridge with sinusitis was first passaged through turkey poults and then assessed for pathogenicity in turkey embryo tracheal organ cultures (tocs) and in one-day-old turkey poults with or without turkey rhinotracheitis virus (trtv). mim appeared to gain virulence on passa ...199818483968
dna amplification methods for diagnosis and epidemiological investigations of avian mycoplasmosis.this review describes some applications of dna amplification methods for diagnosis or epidemiological investigations of avian mycoplasmosis. tests for direct detection of pathogenic mycoplasmas have been developed. moreover, most avian mycoplasma species can be differentiated, according to their unique restriction fragment length polymorphism (rflp) patterns generated after digestion of pcr products with different restriction enzymes. in order to characterize isolates below the species level, pc ...199818483959
natural case of salpingitis apparently caused by mycoplasma gallisepticum in chickens.a natural case of salpingitis, apparently caused by mycoplasma gallisepticum (mg), in layer chickens is described. in the flock from which the chickens originated, there was a 3 to 4% drop in egg production per month around 250 days old. the production was reduced 70% at 400 days of age, which was 77% of the predisease level. salpingitis was characterized by marked thickening of the oviductal mucosa due to epithelial hyperplasia and marked lymphoplasmacytic infiltration. colonization of mg on th ...199718483915
the development of lameness and bone deformity in the broiler following experimental infection with mycoplasma gallisepticum or mycoplasma synoviae.groups of eight 7-day-old mycoplasma-free broiler chicks were inoculated with one of two strains of m. gallisepticum (mg/s6, mg/b31/85) or one of two strains of m. synoviae (ms/b31/88 and ms/b94/91) into the left hock joint. controls were similarly inoculated with sterile mycoplasma broth. the birds were assessed at 2, 3, 4 and 5 weeks of age (1, 2, 3 and 4 weeks post-injection) for lameness and joint and limb lesions. at 5 weeks of age they were killed and examined for gross skeletal abnormalit ...199718483899
the effects of increasing sodium chloride concentration on mycoplasma gallisepticum vaccine survival in solution.lyophilized mycoplasma gallisepticum (mg) vaccines are generally rehydrated and diluted with distilled or chlorine-free water as per manufacturer recommendations. however, as mycoplasma species lack a cell wall, this can lead to decreased viability of live vaccine during administration. the ability of phosphate-buffered saline (pbs) to prevent losses in live vaccine viability was examined. it was shown that a concentration of 1 x pbs prevented the two-fourfold decrease in mg viability seen when ...200818459310
recombinant plasmid constructs expressing gene for antimicrobial peptide melittin for the therapy of mycoplasma and chlamydia infections.in view of growing number of pathogenic microbial strain resistant to routine antibiotics, antimicrobial peptides become promising agents for the therapy of infectious diseases. we studied in vivo effects of melittin, an antimicrobial peptide expressed in a recombinant plasmid vector, on infection with urogenital pathogens chlamydia trachomatis, mycoplasma hominis, and mycoplasma gallisepticum. we obtained recombinant plasmid constructs, where melittin gene is under the control of tetracycline-d ...200718457054
mycoplasma gallisepticum as the first analyzed bacterium in which rna is not polyadenylated.the addition of poly(a)-tails to rna is a phenomenon common to almost all organisms. in addition to most eukaryotic mrnas possessing a stable poly(a)-tail, rna is polyadenylated as part of a degradation mechanism in prokaryotes, organelles, and the eukaryotic nucleus. to date, only very few systems have been described wherein rna is metabolized without polyadenylation, including several archaea and yeast mitochondria. the minimal genome of the parasitic bacteria, mycoplasma, does not encode homo ...200818399989
a survey of avian mycoplasma species for neuraminidase enzymatic activity.among 23 currently recognized avian mycoplasma (am) species only mycoplasma gallisepticum, mycoplasma synoviae, mycoplasma meleagridis and mycoplasma iowae cause disease and loss of production in chickens and/or turkeys. because neuraminidases are considered virulence factors in many pathogenic microorganisms the aim of our study was to determine which am species possess neuraminidase enzymatic activity (neac). small samples of am cells were assayed for neac using the chromogenic substrate 5-bro ...200818372121
comparative assessment of a metabolically attenuated mycoplasma gallisepticum mutant as a live vaccine for the prevention of avian respiratory mycoplasmosis.in a previous study, signature sequence mutagenesis (ssm) was used to identify a mutant with a disruption of the gene encoding the metabolic factor, dihydrolipoamide dehydrogenase, and that mutant was designated mg 7. the current study assessed the safety, immunogenicity and efficacy of mg 7 in comparison to two commercially available vaccines (ts-11 and f) as well as a laboratory vaccine strain, gt5. intratracheal vaccination of chickens with all four attenuated mutants induced varying levels o ...200818342996
effects of time-specific f-strain mycoplasma gallisepticum inoculation overlays on prelay ts11-strain mycoplasma gallisepticum inoculation on performance characteristics of commercial laying hens.mycoplasma bacteria are virtually ubiquitous in layer chicken flocks, and mycoplasma gallisepticum is the species of greatest concern to commercial egg producers. live m. gallisepticum vaccines were initially approved by the usda for use in commercial layers in 1988 to help control m. gallisepticum outbreaks. in the present study, 2 trials were conducted to determine the effects of 2 currently available live mycoplasma vaccines (the ts11-and f-strains) when used together. the following 4 inocula ...200818339985
use of opt-out in a trial of chlamydia screening. 200818334078
effects of supplemental dietary phytase and 25-hydroxycholecalciferol on the performance characteristics of commercial layers inoculated before or at the onset of lay with the f-strain of mycoplasma gallisepticum.the effects of dietary supplementation with phytase and 25-hydroxycholecalciferol on the performance characteristics of commercial layers that were inoculated prelay (12 wk of age) or at the onset of lay (22 wk of age) with f-strain mycoplasma gallisepticum were assessed. experimental layer diets, which included a basal control diet or the same diet supplemented with 0.025% phytase and 25-hydroxycholecalciferol, were fed from 20 through 58 wk of age. weekly and total egg production were determin ...200818281591
effects of 6/85-strain mycoplasma gallisepticum inoculation alone at ten weeks of age or in conjunction with f-strain mycoplasma gallisepticum inoculation overlays at twenty-two or forty-five weeks of age on the performance of commercial egg-laying hens.the effects of 6/85-strain mycoplasma gallisepticum (6/85mg) inoculation alone or in conjunction with a f-strain m. gallisepticum (fmg) overlay and its timing on the performance of commercial egg-laying hens were investigated. control birds received sham inoculations at 10 wk of age. a second treated group of birds was inoculated with 6/85mg at 10 wk of age, a third treatment group of birds was inoculated with 6/85mg at 10 wk and received an overlay of fmg at 22 wk, and a fourth treatment group ...200818281589
molecular survey of avian respiratory pathogens in commercial broiler chicken flocks with respiratory diseases in jordan.acute respiratory tract infections are of paramount importance in the poultry industry. avian influenza virus (aiv), infectious bronchitis virus (ibv), newcastle disease virus (ndv), avian pneumovirus (apv), and mycoplasma gallisepticum (mg) have been recognized as the most important pathogens in poultry. in this study, trachea swabs from 115 commercial broiler chicken flocks that suffered from respiratory disease were tested for aiv subtype h9n2, ibv, ndv, and apv by using reverse transcription ...200818281569
effects of increased dosages of the mycoplasma gallisepticum vaccine mycovac-l in layer chickens subsequently challenged with virulent m. gallisepticum: egg production and serologic response.ten-week-old hy-line commercial w-36 pullets were spray-vaccinated with mycovac-l at the manufacturer's recommended dosage (1x) or at 15 times that rate (15x). at 22 or 45 wk of age, subsets of 1x- and 15x-vaccinated pullets were challenged with the virulent mycoplasma gallisepticum (mg) strain rlow. percent hen-day egg production was determined through week 55. analyses for treatment effects on overall (22-56 wk) percent hen-day egg production revealed no significant differences between nonchal ...200718251402
a recombinant pvpa protein-based diagnostic prototype for rapid screening of chicken mycoplasma gallisepticum infections.mycoplasma gallisepticum is the primary agent of chronic respiratory disease causing important economic losses in the poultry industry. serological monitoring is essential to maintain mycoplasma-free breeder flocks and often complicated by the cross-reactions between different mycoplasma species. to overcome serological cross-reactions, a large fragment of the m. gallisepticum pvpa cytadhesin, species-specific surface-exposed protein, was produced in e. coli as a recombinant protein (rpvpa336) a ...200818248920
displaying the protein of mycoplasma gallisepticum agglutinin on the cell surface of bacillus thuringiensis with the s-layer protein.the s-layer protein ctc surface-display system of bacillus thuringiensis (bt) was used to test the possibility of displaying the protein of mycoplasma gallisepticum (mg) agglutinin (pmga) on the bt cell surface. by fusing part of pmga1.2 (pmga1.2p) with the surface-anchoring motif of ctc, two recombinant plasmids, pctc-pmga1.2p and pcspmga1.2p, were constructed. they harboured the fusion genes ctc-pmga1.2p and csa-ctc-pmga1.2p (csa represents csaab operon, important in anchoring the s-layer prot ...200818243589
structural and functional characterization of an organic hydroperoxide resistance protein from mycoplasma gallisepticum.as obligate parasites, mycoplasma species are continuously exposed to oxidative damage due to host-generated peroxides and reactive oxygen species (ros). in addition, the production of endogenous oxidants is believed to be a primary virulence mechanism of several mollicute species, indicating that oxidative stress resistance is crucial to survival of these bacteria in the host milieu. despite the abundance of oxidants at the site of infection, enzymes responsible for the detoxification of ros ha ...200818192392
strain differentiating real-time pcr for mycoplasma gallisepticum live vaccine evaluation studies.mycoplasma gallisepticum causes respiratory disease and production losses in poultry. vaccination of poultry with m. gallisepticum live vaccines is an approach to reduce susceptibility to infection and to prevent the economic losses. the development and evaluation of live vaccines usually requires the involvement of several vaccine and challenge strains in the same experimental setup. our goal was to develop a tool to allow the differentiation between a set of known m. gallisepticum strains in a ...200818160233
high inter-species and low intra-species variation in 16s-23s rdna spacer sequences of pathogenic avian mycoplasmas offers potential use as a diagnostic tool.in order to investigate its value for phylogenetic analysis, species characterisation and diagnosis, the 16s-23s rdna intergenic spacer regions (isrs) of the type strain of 23 avian mycoplasma species were amplified and the sequences determined. also sequenced were the reference strains of mycoplasma iowae serotypes j, k, n, q and r and a number of field strains of mycoplasma synoviae, mycoplasma gallisepticum, mycoplasma meleagridis and m. iowae. the isrs demonstrated a high level of size varia ...200818055138
chemokine and cytokine gene expression profiles in chickens inoculated with mycoplasma gallisepticum strains rlow or gt5.mycoplasma gallisepticum infection in chickens leads to tracheitis, airsacculitis, poor feed conversion and reduced egg production, resulting in considerable economic hardship on the poultry industry. the chemokines and cytokines responsible for recruitment, activation and proliferation of leukocytes in affected tissues have not been described. in the current study, chemokine and cytokine gene expression profiles were investigated in tracheas of chickens inoculated with m. gallisepticum strains ...200718006123
effects of route of inoculation on mycoplasma gallisepticum infection in captive house finches.the routes by which mycoplasma gallisepticum initiates infection during outbreaks of conjunctivitis in house finches remain uncertain. as m. gallisepticum recovered from the cloaca of chickens remains viable for up to 3 days in chicken faeces, the possibility of spread via faecal contamination has been suggested. to test the hypothesis that food or water contaminated with m. gallisepticum may initiate infection, 20 house finches were experimentally inoculated by the oral or the conjunctival rout ...200717994326
role of phenotypic diversity in pathogenesis of avian mycoplasmosis.the interactions between avian mycoplasmas and their host cells are far more complex than might be anticipated from their apparent structural and functional simplicity. phenotypic diversity in the form of reversible phase variation, antigenic variation or size variation is an adaptive mechanism that enables avian mycoplasmas to survive in a hostile and highly evolved host. despite significant similarities between major membrane antigens of mycoplasma gallisepticum and mycoplasma synoviae, the mo ...200717994321
mycoplasma gallisepticum invades chicken erythrocytes during infection.recently, it was demonstrated using in vitro assays that the avian pathogen mycoplasma gallisepticum is able to invade nonphagocytic cells. it was also shown that this mycoplasma can survive and multiply intracellularly for at least 48 h and that this cell invasion capacity contributes to the systemic spread of m. gallisepticum from the respiratory tract to the inner organs. using the gentamicin invasion assay and a differential immunofluorescence technique combined with confocal laser scanning ...200817954728
mycoplasma gallisepticum infection in house finches (carpodacus mexicanus) affects mosquito blood feeding patterns.disease-induced lethargy can diminish host capacity to repel or kill biting mosquitoes. we exposed house finches (carpodacus mexicanus) to mosquitoes (culex pipiens pipiens), repeated the experiment after inoculating finches with mycoplasma gallisepticum, and then repeated the experiment with the same birds after curing their infections. we videotaped avian behaviors before and during mosquito exposure, identifying hosts through blood meal dna fingerprinting. results revealed heterogeneity in mo ...200717827365
identification of major immunogenic proteins of mycoplasma synoviae isolates.mycoplasma synoviae isolates differ in patterns of immunogenic proteins, but most of them have not been identified yet. the main aim of this study was their identification in two closely related m. synoviae isolates, ulb 02/p4 and ulb 02/ov6, recovered recently from chickens in slovenia. n-terminal sequencing identified 17 m. synoviae proteins. amongst them were 14 major, highly expressed but previously unidentified proteins, including enzymes, chaperones and putative lipoproteins. ulb 02/p4 pro ...200817720337
effects of supplemental dietary phytase and 25-hydroxycholecalciferol on the digestive and reproductive organ characteristics of commercial layers inoculated before or at the onset of lay with the f-strain of mycoplasma gallisepticum.in 3 trials, the effects of dietary supplementation with phytase (phy) and 25-hydroxycholecalciferol (25-d3) on the digestive and reproductive organ characteristics of commercial layers that were inoculated prelay (12 wk of age) or at the onset of lay (22 wk of age) with f-strain mycoplasma gallisepticum (fmg) were assessed at 58 wk of age. experimental layer diets that included a basal control diet or a control diet supplemented with 0.025% phy and 25-d3 were fed from 20 through 58 wk of age. a ...200717626828
the mycoplasma gallisepticum 16s-23s rrna intergenic spacer region sequence as a novel tool for epizootiological studies.mycoplasma gallisepticum (mg) contains two sets of rrna genes (5s, 16s and 23s) in its genome, but only one of the two is organized in an operon cluster and contains a unique 660-nucleotide intergenic spacer region (igsr) between the 16s and the 23s rrna genes. we designed a polymerase chain reaction (pcr) for the specific amplification of the complete mg igsr segment. the mg igsr pcr was tested on 18 avian mollicute species and was confirmed as mg specific. the reaction sensitivity was demonstr ...200717626483
molecular characterization and determination of antimicrobial resistance of mycoplasma gallisepticum isolated from chickens.in this study, three consecutive approaches of molecular characterization, determination of minimum inhibitory concentration (mic) and antimicrobial tested on mycoplasma gallisepticum (mg) isolated from chicken farms were investigated. these approaches were conducted between 2004 and 2005 to 134 mg samples collected from five different regions of the intensive farming area of thailand. twenty mg isolates and four reference strains including s6, f, ts-11, and 6/85 were classified according to ran ...200717570621
synthetic biology. attempt to patent artificial organism draws a protest. 200717569837
transcriptional responses of mycoplasma gallisepticum strain r in association with eukaryotic cells.mycoplasma gallisepticum is an etiologic agent of chronic respiratory disease in chickens and infectious sinusitis in turkeys. other than proteins important for cytadherence, few m. gallisepticum factors or pathways contributing to host cell interactions have been identified. in this study, an oligonucleotide-based microarray was utilized to investigate transcriptional changes in m. gallisepticum strain r(low) upon exposure to eukaryotic cells. fifty-eight genes were either up- or downregulated ...200717557819
contrasting natural experiments confirm competition between house finches and house sparrows.after house finches were introduced from the western to the eastern united states and rapidly increased in numbers, house sparrows declined, leading to suggestions that the decline was caused by interspecific competition. however, other potential causes were not excluded. the rapid decline in house finches following the emergence of a new disease (mycoplasmal conjunctivitis) caused by a novel strain of mycoplasma gallisepticum (mg) in 1994 has provided a natural experiment and an opportunity to ...200717536703
experimental evidence for transmission of mycoplasma gallisepticum in house finches by fomites.ever since mycoplasma gallisepticum emerged among house finches in north america, it has been suggested that bird aggregations at feeders are an important cause of the epidemic of mycoplasmal conjunctivitis because diseased birds could deposit droplets of pathogen onto the feeders and thereby promote indirect transmission by fomites. in this paper we bring the first experimental evidence that such transmission (bird-to-feeder-to-bird) does actually take place. house finches infected via this rou ...200717497332
survey of campylobacter, salmonella and mycoplasmas in house crows (corvus splendens) in malaysia.house crows (corvus splendens) in selangor, malaysia were examined for the presence of campylobacter species, salmonella species, mycoplasma gallisepticum and mycoplasma synoviae by serology, culture and pcr. for the detection of campylobacter and salmonella species swabs were taken either from the intestine or cloaca. for the detection of mycoplasmas, swabs were taken either from the choanal cleft or trachea for culture and pcr and serum samples were tested by the rapid serum agglutination (rsa ...200717483380
state-specific detection probabilities and disease prevalence.investigations of disease dynamics in wild animal populations often use estimated prevalence or incidence as a measure of true disease frequency. such indices, almost always based solely on raw counts of infected and uninfected individuals, are often used as the basis for analysis of temporal and spatial dynamics of diseases. generally, such studies do not account for potential differences in observer detection probabilities of host individuals stratified by biotic and/or abiotic factors. we dem ...200717479842
interlaboratory comparison of ability to detect nucleic acid of mycoplasma gallisepticum and mycoplasma synoviae by polymerase chain reaction.in recent years polymerase chain reaction (pcr) assays have become widely used as methods to confirm the presence of mycoplasma gallisepticum and mycoplasma synoviae in poultry flocks, but there has been limited standardization of the protocols used. thirteen laboratories from five different countries participated in an interlaboratory comparison of detection of m. gallisepticum and m. synoviae dna by pcr in samples that contained 10-fold dilutions of these bacteria. the concentration of bacteri ...200717479373
the mycoplasma gallisepticum osmc-like protein mg1142 resides on the cell surface and binds heparin.mycoplasma gallisepticum is an avian pathogen that causes a chronic respiratory disease of chickens and results in significant economic losses to the poultry industry worldwide. colonization of the host and the establishment of chronic disease are initiated by the cytadherence of m. gallisepticum to the host respiratory epithelium. while several proteins involved in cytadhesion have been characterized, molecules that interact with components of the host extracellular matrix, a process that is ce ...200717464059
experimental infection of chickens and turkeys with mycoplasma gallisepticum reference strain s6 and north carolina field isolate rapd type b.during an epidemic of mycoplasmosis in chicken and turkey flocks in north carolina between 1999 and 2001, isolates of mycoplasma gallisepticum (mg) from affected flocks were characterized by random amplification of polymorphic dna (rapd), and eight distinct rapd types were identified. mg rapd type b accounted for more than 90% of the isolates and was associated with moderate-to-severe clinical signs and mortality. the virulence of mg rapd type b for chickens and turkeys was compared with sham-in ...200717461274
effects of supplemental dietary phytase and 25-hydroxycholecalciferol on the blood characteristics of commercial layers inoculated before or at the onset of lay with the f-strain of mycoplasma gallisepticum.in 3 trials, the effects of dietary supplementation with phytase (phy) and 25-hydroxycholecalciferol on bw and the blood characteristics of commercial layers that were inoculated prelay (12 wk of age) or at the onset of lay (22 wk of age) with f-strain mycoplasma gallisepticum were assessed at 34, 50, and 58 wk of age. experimental layer diets, which included either a basal control diet or the same diet supplemented with 0.025% phy and 25-hydroxycholecalciferol, were fed from 20 through 58 wk of ...200717369552
differentiation of mycoplasma gallisepticum strains using molecular methods.increasing use of mycoplasma gallisepticum (mg) live vaccines has led to a need for the differentiation of mg strains. the mg strains mk-7, ms-16, s6, fs-9 and r strains and the mg live vaccine strain f were compared by random amplification of polymorphic dna (rapd) in this study. using rapd, different patterns were found among the mg strains. in addition to this, we examined the differentiating potential of polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) primers ta ...200617278716
separating mycoplasma gallisepticum field strains from nonpathogenic avian mycoplasmas.mycoplasma gallisepticum (mg) has repeatedly emerged as a serious problem in u.s. broiler, layer, and turkey industries. tracing the source of an outbreak is essential if mg control is to be accomplished. amplified fragment length polymorphism (aflp), random amplification of polymorphic dna (rapd), and restriction fragment length polymorphism (rflp) are valuable tools used to study mg epidemiology, allowing diagnosticians to determine the source of mg infections. in some past outbreaks, aflp, ra ...200617274301
development and validation of a real-time taqman polymerase chain reaction assay for the detection of mycoplasma gallisepticum in naturally infected birds.in this study, we report the development and validation of a real-time polymerase chain reaction (pcr) assay using a taqman-labeled probe for the detection of mycoplasma gallisepticum (mglp assay). the mglp assay was highly specific with a detection limit of 25 template copies per reaction and a quantification limit of 100 template copies per reaction. validation of the assay was completed with 1247 samples (palatine cleft and tracheal swabs) from m. gallisepticum-positive and -negative chicken ...200617274291
spatial spread of an emerging infectious disease: conjunctivitis in house finches.in this paper we quantify the rate of spread of the newly emerged pathogen mycoplasma gallisepticum of the house finch, carpodacus mexicanus, in its introduced range. we compare and contrast the rapid, yet decelerating, rate of spread of the pathogen with the slower, yet accelerating rate of spread of the introduced host. comparing the rate of spread of this pathogen to pathogens in terrestrial mammalian hosts, we see that elevation and factors relating to host abundance restrict disease spread, ...200617249229
genetic diversity predicts pathogen resistance and cell-mediated immunocompetence in house finches.evidence is accumulating that genetic variation within individual hosts can influence their susceptibility to pathogens. however, there have been few opportunities to experimentally test this relationship, particularly within outbred populations of non-domestic vertebrates. we performed a standardized pathogen challenge in house finches (carpodacus mexicanus) to test whether multilocus heterozygosity across 12 microsatellite loci predicts resistance to a recently emerged strain of the bacterial ...200517148199
evolutionary genetics of carpodacus mexicanus, a recently colonized host of a bacterial pathogen, mycoplasma gallisepticum.we present molecular data documenting how introduction to the eastern united states and an epizootic involving a bacterial pathogen has affected the genetic diversity of house finches, a cardueline songbird. population bottlenecks during introduction can cause loss of genetic variation and may negatively affect a population's ability to adapt to novel stressors such as disease. although a genome-wide survey using amplified fragment length polymorphism (aflp) markers suggests little loss of genet ...200717103248
molecular characterization of mg isolates using rapd and pfge isolated from chickens in brazil.in the present study, 27 primers were screened under different cycles by random amplified polymorphic dna (rapd) method. mathematical models were used for analysis of the genetic relationships among strains, including vaccinal, reference strains and nine field isolates previously characterized as mycoplasma gallisepticum (mg)f by rapd and pulsed field gel electrophoresis (pfge). the pfge was considered as laborious, expensive and time-consuming than rapd method. these methods improved the typeab ...200617062123
effects of s6-strain mycoplasma gallisepticum inoculation at ten, twenty-two, or forty-five weeks of age on the blood characteristics of commercial egg-laying hens.in 2 consecutive trials of the current study, the effect of the age of application of s6-strain mycoplasma gallisepticum (s6mg) inoculation on the blood characteristics of commercial layers housed and maintained under controlled conditions was determined. the ages of inoculation compared were those before lay at 10 wk of age, during onset of lay at 22 wk of age, and during postpeak lay at 45 wk of age. in each trial, hematocrit, plasma protein, and serum cholesterol, triglycerides, and ca were d ...200617032838
the effect of a live vaccine on the horizontal transmission of mycoplasma gallisepticum.the effect of a live mycoplasma gallisepticum vaccine on the horizontal transmission of this mycoplasma species was quantified in an experimental animal transmission model in specific pathogen free white layers. two identical trials were performed, each consisting of two experimental groups and one control group. the experimental groups each consisted of 20 birds 21 weeks of age, which were housed following a pair-wise design. one group was vaccinated twice with a commercially available live att ...200616990145
serological survey of the infectious disease status of old english game fowl in the lower north island, new zealand.to investigate the serological status of old english game (oeg) cockerels for a range of infectious diseases of poultry.200616915341
effects of s6-strain mycoplasma gallisepticum inoculation at ten, twenty-two, or forty-five weeks of age on the egg yolk composition of commercial egg-laying hens.commercial laying hens maintained under controlled conditions were experimentally inoculated with the s6 strain of mycoplasma gallisepticum (s6mg) at 45 wk of age. this resulted in depressed liver lipid concentration, and inoculations at 20 and 45 wk affected the size of various portions of the reproductive tract. in 2 consecutive trials of the current study, the effect of age of application of s6mg inoculation on the egg yolk characteristics of commercial layers similarly housed and maintained ...200616903485
further western spread of mycoplasma gallisepticum infection of house finches.mycoplasma gallisepticum, an important pathogen of poultry, especially chickens and turkeys, emerged in 1994 as the cause of conjunctivitis in house finches (carpodacus mexicanus) in their eastern range of north america. the resulting epidemic of m. gallisepticum conjunctivitis severely decreased house finch abundance and the continuing endemic disease in the eastern range has been associated with repeating seasonal peaks of conjunctivitis and limitation of host populations. mycoplasma gallisept ...200616870870
genotypic analyses of mycoplasma gallisepticum isolates from songbirds by random amplification of polymorphic dna and amplified-fragment length polymorphism.mycoplasma gallisepticum (mg) conjunctivitis emerged in 1994 as a disease of free-ranging house finches (carpodacus mexicanus) in north america and has also been isolated from other songbirds with conjunctivitis. random amplification of polymorphic dna (rapd) of house finch and other songbird isolates has suggested that a single 'strain' initiated this outbreak. to explore the possibility of genomic variability among house finch isolates of mg and to evaluate the utility of a second technique fo ...200616870869
ultrastructure and gliding motility of mycoplasma amphoriforme, a possible human respiratory pathogen.despite their small size and reduced genomes, many mycoplasma cells have complex structures involved in virulence. mycoplasma pneumoniae has served as a model for the study of virulence factors of a variety of mycoplasma species that cause disease in humans and animals. these cells feature an attachment organelle, which mediates cytadherence and gliding motility and is required for virulence. an essential component of the architecture of the attachment organelle is an internal detergent-insolubl ...200616804191
mycoplasma genitalium mg200 and mg386 genes are involved in gliding motility but not in cytadherence.isolation and characterization of transposon-generated mycoplasma genitalium gliding-deficient mutants has implicated mg200 and mg386 genes in gliding motility. the proposed role of these genes was confirmed by restoration of the gliding phenotype in deficient mutants through gene complementation with their respective mg386 or mg200 wild-type copies. mg200 and mg386 are the first reported gliding-associated mycoplasma genes not directly involved in cytadherence. orthologues of mg200 and mg386 pr ...200616796684
effects of s6-strain mycoplasma gallisepticum inoculation at 10, 22, or 45 weeks of age on the digestive and reproductive organ characteristics of commercial egg-laying hens.experimental inoculation of commercial laying hens with the s6-strain of mycoplasma gallisepticum (s6mg) at 20 wk of age, while being maintained under ideal conditions, has previously been shown to affect the lengths and weights of various portions of the reproductive tract. two trials were conducted in the current study to compare the effects of s6mg inoculation prior to lay at 10 wk of age, during onset of lay at 22 wk of age, and during lay at 45 wk of age on the digestive and reproductive or ...200616673758
a cdna macroarray approach to parasite-induced gene expression changes in a songbird host: genetic response of house finches to experimental infection by mycoplasma gallisepticum.in 1994, the bacterial parasite mycoplasma gallisepticum expanded its host range and swept through populations of a novel host--eastern us populations of the house finch (carpodacus mexicanus). this epizootic caused a dramatic decline in finch population numbers, has been shown to have caused strong selection on house finch morphology, and presumably caused evolutionary change at the molecular level as finches evolved enhanced resistance. as a first step toward identifying finch genes that respo ...200616626453
characterization of experimental mycoplasma gallisepticum infection in captive house finch flocks.the use of controlled, horizontal-transmission experiments provides detailed information on the spread of disease within fixed social groups, which informs our understanding of disease dynamics both in an empirical and theoretical context. for that reason, we characterized in 2002, horizontal transmission of mycoplasma gallisepticum (mg) in two flocks of 11 wild-caught house finches housed in outdoor aviaries over a 6-mo period. all birds were initially free of mg by a polymerase chain reaction ...200616617979
ultrastructure and ribosomes of mycoplasma gallisepticum.maniloff, jack (yale university, new haven, conn.), harold j. morowitz, and russell j. barrnett. ultrastructure and ribosomes of mycoplasma gallisepticum. j. bacteriol. 90:193-204. 1965.-the ultrastructure of mycoplasma gallisepticum strain a5969 has been studied by electron microscopy (thin-section and negative staining), ultracentrifugation, and chemical analysis. the list of ultrastructure is: membrane, nuclear material, ribosomes, ribosomal structures, infra-bleb region, and blebs. the nucle ...196516562017
transfer of maternal immunoglobulins and antibodies to mycoplasma gallisepticum and mycoplasma synoviae to the allantoic and amniotic fluid of chicken embryos.maternal antibodies can protect avian embryos against vertically transmitted pathogens during embryogenesis and also young birds after hatching. in contrast to the well-known transfer of maternal immunoglobulin (ig) g (also termed igy) from the yolk to embryonic blood, information about the transfer of iga, igg and igm from the egg albumen to the extra-embryonic fluids is very limited. in our study, iga, igg and igm to mycoplasma gallisepticum and mycoplasma synoviae were detected in oviduct was ...200516537160
identification of fibronectin-binding proteins in mycoplasma gallisepticum strain r.we have determined that virulent mycoplasma gallisepticum strain rlow is capable of binding the extracellular matrix protein fibronectin. fibronectin was found to be present in m. gallisepticum rlow protein extracts by western blotting and peptide sequencing. mycoplasma gallisepticum rhigh, the attenuated, high-passage derivative of rlow, is deficient in this ability. mga_1199, the m. gallisepticum homologue of the cytadherence-associated protein p65 from mycoplasma pneumoniae, and mga_0928, the ...200616495551
effects of s6-strain mycoplasma gallisepticum inoculation at ten, twenty-two, or forty-five weeks of age on the performance characteristics of commercial egg laying hens.experimental inoculation of commercial laying hens, maintained under controlled conditions, with the s6-strain of mycoplasma gallisepticum (s6mg) at 10 wk of age has previously been shown to affect the lengths and weights of various portions of the reproductive tract without affecting subsequent performance. two trials were conducted to compare the effects of s6mg inoculation at 10 wk of age (prior to lay), 22 wk of age (onset of lay), and 45 wk of age (during lay) on performance characteristics ...200516463961
the effect of vaccination with a bacterin on the horizontal transmission of mycoplasma gallisepticum.the effect of an inactivated vaccine on the horizontal transmission of mycoplasma gallisepticum was quantified in a transmission model. twenty non-vaccinated and 20 vaccinated 23-week-old specific pathogen free hens were housed in pairs, while five individually housed hens acted as a negative control group. each pair consisted of a challenged chicken (10(4) colony forming units intratracheally) and a non-challenged susceptible contact bird. infection was monitored by serology, quantitative polym ...200616448940
identification of a virulence-associated determinant, dihydrolipoamide dehydrogenase (lpd), in mycoplasma gallisepticum through in vivo screening of transposon mutants.to effectively analyze mycoplasma gallisepticum for virulence-associated determinants, the ability to create stable genetic mutations is essential. global m. gallisepticum mutagenesis is currently limited to the use of transposons. using the gram-positive transposon tn4001mod, a mutant library of 110 transformants was constructed and all insertion sites were mapped. to identify transposon insertion points, a unique primer directed outward from the end of tn4001mod was used to sequence flanking g ...200616428737
the cellular immune response in the tracheal mucosa to mycoplasma gallisepticum in vaccinated and unvaccinated chickens in the acute and chronic stages of disease.mycoplasma gallisepticum causes a lymphoproliferative response in the tracheal mucosa of infected birds. the studies reported here aimed to determine, using immunohistochemical and immunofluorescent staining, which lymphocyte subsets were infiltrating the mucosa during the acute and chronic phases of disease and to determine whether these subsets differed in birds that had been vaccinated with strain ts-11. in vaccinates there was no detectable infiltration of t or b lymphocytes between 1 and 6 ...200616406173
mycoplasma gallisepticum hemagglutinin v1ha, pyruvate dehydrogenase pdha, lactate dehydrogenase, and elongation factor tu share epitopes with mycoplasma imitans homologues.mycoplasma gallisepticum is a major pathogen of poultry. mycoplasma imitans is genetically and antigenically closely related to m. gallisepticum, but so far, only a few proteins of m. imitans have been identified as sharing epitopes with m. gallisepticum. in this study, we identified three proteins of m. gallisepticum that share with m. imitans epitopes defined by monoclonal antibodies (mabs). mab 9d4 reacted with the 67-kd hemagglutinin v1ha (previously termed pmga) of m. gallisepticum and with ...200516404991
age related differences in the immune response to vaccination and infection with mycoplasma gallisepticum.several studies have suggested that there are age related differences in the responses of chickens to vaccination and infection with mycoplasma gallisepticum, but there have not been any systematic comparisons of the responses of young birds to vaccination with those of birds the same age to infection. the aim of the studies described here was to examine the immune responses of chickens between 1 and 6 weeks of age to vaccination and to infection with m. gallisepticum. birds under 4 weeks of age ...200616288936
genotyping of mycoplasma gallisepticum and m. synoviae by amplified fragment length polymorphism (aflp) analysis and digitalized random amplified polymorphic dna (rapd) analysis.mycoplasma gallisepticum (mg) and m. synoviae (ms) are the cause of considerable economic losses in the poultry industry. molecular differentiation of avian mycoplasma strains may be helpful in tracing infections and in the evaluation of implemented intervention strategies. amplified fragment length polymorphism (aflp) has shown to be a powerful typing technique but the application for poultry mycoplasma strains is very limited. the aim of this study was to evaluate the reproducibility and discr ...200516236471
an experimental model to quantify horizontal transmission of mycoplasma gallisepticum.before interventions to control horizontal transmission of mycoplasma gallisepticum can be tested, a suitable experimental model should be available. transmission dynamics in a flock can be quantified by two parameters: the average number of secondary cases infected by one typical infectious case (r0) and the number of new infections that occur due to one infectious animal per unit of time (beta). the transmission dynamics of m. gallisepticum have not been studied experimentally, so the aim of t ...200516147573
real-time polymerase chain reaction for the qualitative and quantitative detection of mycoplasma gallisepticum.the aim of this study was to evaluate the sensitivity and the detection limit of a real-time polymerase chain reaction (q-pcr) developed for the qualitative and quantitative detection of mycoplasma gallisepticum. no cross-reactivity was observed with dna from other important avian mycoplasmas, including mycoplasma synoviae and mycoplasma meleagridis. however, the q-pcr could not distinguish between m. gallisepticum and mycoplasma imitans. the q-pcr had detection limits 10 to 1000 times lower tha ...200516147572
safety and efficacy of mycoplasma gallisepticum ts-11 vaccine for the protection of layer pullets against challenge with virulent m. gallisepticum r-strain.mycoplasma gallisepticum ts-11 vaccine was studied for its safety and protective ability in 49-day-old m. gallisepticum-free and mycoplasma synoviae-free commercial tetra sl layer chickens. sixty birds were distributed into four groups: 15 were unvaccinated but were challenged with m. gallisepticum r-strain, 15 were vaccinated by eye drop and then challenged with virulent m. gallisepticum r-strain 4 weeks post vaccination, 15 were designated as controls without vaccination and challenge, and 15 ...200516147571
differential detection of turkey coronavirus, infectious bronchitis virus, and bovine coronavirus by a multiplex polymerase chain reaction.the objective of the present study was to develop a multiplex polymerase chain reaction (pcr) method for differential detection of turkey coronavirus (tcov), infectious bronchitis coronavirus (ibv), and bovine coronavirus (bcov). primers were designed from conserved or variable regions of nucleocapsid (n) or spike (s) protein gene among tcov, ibv, and bcov and used in the same pcr reaction. reverse transcription followed by the pcr reaction was used to amplify a portion of n or s gene of the cor ...200616137773
correlates of immune protection in chickens vaccinated with mycoplasma gallisepticum strain gt5 following challenge with pathogenic m. gallisepticum strain r(low).colonization of the avian respiratory tract with mycoplasma gallisepticum results in a profound inflammatory response in the trachea, air sacs, conjunctiva, and lungs. a live attenuated m. gallisepticum vaccine strain, gt5, was previously shown to be protective in chickens upon challenge; however, the mechanisms by which this vaccine and others confer protection remain largely unknown. the current study evaluated several potential correlates of gt5 vaccine-mediated immune protection following ch ...200516113257
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