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
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
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
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
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
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
high inter-species and low intra-species variation in 16s-23s rdna spacer sequences of pathogenic avian mycoplasmas offers potential use as a diagnostic 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
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
structural and functional characterization of an organic hydroperoxide resistance protein from mycoplasma 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
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
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
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
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 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
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
use of opt-out in a trial of chlamydia screening. 200818334078
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
comparative assessment of a metabolically attenuated mycoplasma gallisepticum mutant as a live vaccine for the prevention of avian respiratory 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
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
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
recombinant plasmid constructs expressing gene for antimicrobial peptide melittin for the therapy of mycoplasma and chlamydia 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
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
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
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
effect of duration of incubation of mycoplasma gallisepticum cultures on the sensitivity and specificity of antigens for elisa and microimmunofluorescence 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
indirect elisa for the detection of a specific antibody response against mycoplasma 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
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
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
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
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
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
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
the use of a specific dna probe for detection of mycoplasma gallisepticum in field outbreaks.a specific dna probe (pmg4) was used to diagnose m. gallisepticum (mg) infection in field outbreaks in chicken and turkey breeder flocks in israel. dot-blot hybridisation of tracheal swab suspensions with the probe enabled positive identification of mg as early as 4 days after sampling, even in flocks at an early stage of infection when no other specific indications of infection were available.198918679883
effects of baytril, tylosin and tiamulin on avian mycoplasmas.the minimum inhibitory concentration (mic) of baytril, tylosin and tiamulin for strains of mycoplasma gallisepticum (mg) m. synoviae (ms), m. meleagridis (mm) and m. iowae (mi) and serovars were compared. in general the lowest mic for mg, ms and mi was obtained with baytril, while for mm both baytril and tiamulin gave the lowest mics. protection against mortality was best attained with baytril for broiler chicks and poults but against prevention of growth depression baytril was best for broiler ...198918679898
studies in vivo on the efficacy of enrofloxacin against mycoplasma gallisepticum.after a 5-day medication with drinking water containing 50 ppm enrofloxacin, mycoplasma gallisepticum (mg) was culturally reisolated in only one of 80 broiler chicks and specific antibodies to mg were detected in none of the 40 birds tested. medication with 50 ppm for 3 days and 25 ppm for 5 days was only slightly less effective. a significant decline in efficacy was observed, however, when enrofloxacin was added to the drinking water at 50 ppm for 1 day or 12.5 ppm for 5 days. tiamulin was also ...199018679962
development and immunogenicity of recombinant mycoplasma gallisepticum vaccine strain ts-11 expressing chicken ifn-gamma.mycoplasma gallisepticum (mg) is a poultry pathogen that causes respiratory disease and loss of egg production worldwide. a live attenuated vaccine, ts-11, has been used for the control of mg in several countries. to improve the functionality of the vaccine and investigate its potential as a delivery vector for host immune molecules and foreign antigens, we have developed ts-11 as a vector to express and secrete chicken ifn-gamma (ts-11 c3) using a transposon-based delivery vector. following adm ...200818706959
the potential impact of disease on the migratory structure of a partially migratory passerine population.since its introduction into eastern north america in the 1940s, the eastern population of house finches (carpodacus mexicanus) has become partially migratory, unlike its nonmigratory source population in southern california (able and belthoff in proc. r. soc. lond. 265 (1410), 2063-2071, 1998; belthoff and gauthreaux in condor 93, 374-382, 1991). the infectious disease mycoplasmal conjunctivitis (pathogen mycoplasma gallisepticum or "mg"), which has been monitored in the house finch population s ...200818716845
development of a replicable oric plasmid for mycoplasma gallisepticum and mycoplasma imitans, and gene disruption through homologous recombination in m. gallisepticum.the genome of mycoplasma gallisepticum strain r(low) has been sequenced completely, but subsequent genetic studies have been limited by the lack of a replicable vector system. in this study, replicable plasmids were constructed for m. gallisepticum and mycoplasma imitans using the oric region upstream from the soj gene. the oric plasmids of m. gallisepticum (pgtlori) and m. imitans (pmiori) replicated in both species, but mycoplasma pneumoniae could not support replication of pgtlori. a 180 bp s ...200818757791
comparison of in vivo and in vitro methods for pathogenicity evaluation for mycoplasma gallisepticum in respiratory infection.this study was designated to examine the pathogenicity of several strains of mycoplasma gallisepticum (r, f, s-6, 227 and a5969) and laboratory derived substrains. preliminary results indicated that the nine m. gallisepticum strains differed markedly in their pathogenicity for chickens. a comparison was made between various in vivo and in vitro methods for quantitative evaluation of pathogenicity. reproducibility, convenience, and relevance to clinical observations were considered. two in vivo t ...198618766523
isolation of mycoplasma gallisepticum from geese.two breeding flocks of 2-year-old geese in the landes region of southwest france were cultured for mycoplasmas. in one flock of 134 birds mycoplasma gallisepticum was isolated from three individuals, from a different site in each bird (i.e. oesophagus, trachea, cloaca). m. gallisepticum was also isolated from the semen of one goose in the other flock of 70 birds, but in neither flock could the true incidence be determined because of prolific overgrowth by acholeplasmas in nearly all the samples.198618766559
an inactivated temperature-sensitive mycoplasma gallisepticum mutant for protection against airsacculitis.a formalinised temperature-sensitive (ts) mutant of mycoplasma gallisepticum (mg) emulsified in complete freund's adjuvant was capable of protecting chickens against airsacculitis after intra-air sac challenge with the virulent s6 strain at a statistically significant level. formalinised ts mg vaccine without the addition of adjuvant yielded inconsistent results, and the outcome may have been dependent upon the dosage used.198718766639
natural infection of ducks with mycoplasma synoviae and mycoplasma gallisepticum and mycoplasma egg transmission.mycoplasma gallisepticum (mg), m. synoviae (ms), m. cloacale (mc) and m. anatis were isolated from ducks kept in a yard in close contact with chickens that were infected with mg, ms and some other avian mycoplasma species. mg, ms and mc were isolated also from embryonated duck eggs and from infertile duck eggs laid during the first four weeks of egg production. infected ducks did not show clinical signs of mg or ms infection in chicken. detectable mg and ms agglutinating antibodies were not pres ...198818766701
examination of mycoplasma gallisepticum strains using restriction endonuclease dna analysis and dna-dna hybridisation.dna from 10 mycoplasma gallisepticum strains and one strain each of m. synoviae and m. gallinarum were studied by restriction endo-nuclease dna analysis using endonucleases eco ri, hindiii, bglii, bamhi, kpni, and xhoi. digestion patterns of dna in agarose gels allowed easy differentiation of m. gallisepticum strains from different sources, while patterns obtained from one strain at the 6th and 100th in vitro passage levels were identical. the f strain and a field derivative obtained from a poul ...198818766716
[experimental infection with mycoplasma gallisepticum: influence of ammonia as an exacerbating factor].five-week-old spf chickens were inoculated with a virulent strain of m. gallisepticum and half were exposed to an atmosphere containing 100 ppm ammonia. the inoculation reduced weight gain and induced general and respiratory signs (prostration, tracheal rales, and snoring). tracheal cilial movement was stopped. the severity and duration of m. gallisepticum infection were exacerbated by exposure to ammonia.198818766719
pathogenicity for chickens of six strains of mycoplasma gallisepticum isolated from various birds.pathogenicity of the type strain and five field strains of mycoplasma gallisepticum isolated from various avian hosts was evaluated by chicken inoculation. only two field strains isolated from chickens were highly pathogenic for the chicken respiratory tract.198818766728
natural infection of geese with mycoplasma gallisepticum and mycoplasma synoviae and egg transmission of the mycoplasmas.mycoplasma gallisepticum (mg) and m. synoviae (ms) were isolated from geese kept for more than a year on a multiple-age chicken farm. agglutinating antibodies against mg and ms were found in the sera of some geese which were positive also in the haemagglutination-inhibition tests. the isolation of mg and ms from several organs of goose embryos indicates that egg transmission occurs. it is probably the first report concerning isolation of ms from the naturally infected geese and furthermore conce ...198818766753
a correlative in vivo study of the surface morphology and colonisation of the chicken trachea infected by mycoplasma gallisepticum strains r and f.the pathogenic processes occurring in the chicken trachea as the result of infection by mycoplasma gallisepticum were followed at frequent intervals over a 2-week period after introduction of the organism into the trachea. a correlation was made between changes in the surface morphology of the trachea, as seen by the scanning electron microscope, and mycoplasma colonisation of the upper respiratory tract, as evaluated in isolation studies. effects of the clinical status of the birds were indicat ...198318766781
cloacal infection with mycoplasma gallisepticum and the effect of inoculation with h120 infectious bronchitis vaccine virus.infectivity of an isolate of mycoplasma gallisepticum of low virulence was studied in specific pathogen free chickens from 1 day old until after the onset of lay. widespread cloacal infection developed and it was discussed in relation to the low serological response. the effects produced by inoculation of h120 infectious bronchitis vaccine virus and coming into lay were associated with changes in serological response and increased cloacal cultural recovery. the possibility of ascending cloacal i ...198318766808
experimental studies on turkey coryza.disease with severe respiratory symptoms, nasal discharge, swelling of sinuses, conjunctivitis with foamy discharge and mortality has been observed in turkey flocks in israel. of the pathogenic agents isolated from field cases, three, paramyxovirus, yucaipa (yucaipa virus), alcaligenes faecalis (a. faecalis) and mycoplasma gallisepticum (mg) were used to infect turkey poults, singly or in combination, in our attempt to reproduce the field disease symptoms. yucaipa virus alone caused mild symptom ...198418766831
the minimum inhibitory concentration of kitasamycin, tylosin and tiamulin for mycoplasma gallisepticum and their protective effect on infected chicks.the minimum inhibitory concentration (m.i.c.) of kitasamycin, tylosin and tiamulin for mycoplasma gallisepticum (mg) were compared with 10(6), 10(4), and 10(2) cfu/ml of the organisms with the drug incorporated in mycoplasma agar. the lowest m.i.c. was obtained with tiamulin and the highest with kitasamycin and, in general, the m.i.c.'s were directly influenced by the concentration of mycoplasmas. chick embryos at 19 days of incubation were infected with mg and the hatched infected chicks were u ...198418766833
microcomputer-assisted morphometric analysis of airsacculitis caused by mycoplasma gallisepticum in immunised and nonimmunised chickens.inflammation caused by inoculation of mycoplasma gallisepticum (mg) into the air sacs was compared in chickens previously exposed by intramuscular injection of mg with that produced in nonimmunised chickens. air sacs from chickens inoculated with frey's media, from those receiving only intramuscular injections of mg, and from nonimmunised non-challenged birds were included in the evaluations. the airsacculitis produced in immunised chickens was more severe at 48 hours post-challenge infection th ...198418766867
[avian mycoplasmosis: comparative study of the plate agglutination test, haemagglutination inhibition test and metabolic inhibition test for detection of antibody against mycoplasma gallisepticum].this study was performed with the use of the mg/s6 strain of mycoplasma gallisepticum, reference sera, sera from vaccinated chickens (given at inactivated vaccine) and sera from infected turkeys in the field. titres of antibody detected were well correlated for the three tests. however, the plate agglutination test (pat) allowed the earliest detection, and metabolic inhibition test (mit) was as sensitive and specific as the haemagglutination inhibition test (hit). mit allowed a good repeatabilit ...198418766885
[respiratory diseases of the fowl:principles of histopathological diagnosis].groups of specific pathogen free chickens were inoculated with five strains of newcastle disease virus, one strain of adenovirus, four strains of infectious bronchitis virus, one strain of mycoplasma gallisepticum and with infectious bronchitis virus together with mycoplasma gallisepticum. lungs and tracheas were taken at regular intervals for histopathological examination. a diagnosis could be based on tracheal lesions at different periods of their development. newcastle disease was distinguish ...197718770313
survival of mycoplasma gallisepticum in mains water.the survival of two strains of mycoplasma gallispeticum in mains water at room temperature depended on the initial number of organisms and the incorporation of mycoplasma broth in the suspending medium. seven to 8 log(10) colony forming units (cfu) ml were needed for survival for 1 day in sterile water. in water with 1% (vol/vol) broth at least 6 log(10 )cfu/ml were needed for survival, which was prolonged to 4 days. in water with 10% broth 1 to 4 log(10) cfu/ml could survive for 9 to 10 days, w ...197718770315
the detection of maternal antibodies to mycoplasma gallisepticum in chicks by the rapid serum agglutination and haemagglutination inhibition tests.eggs from hens infected with mycoplasma gallisepticum and hens free from m. gallisepticum and m. synoviae were hatched and samples of blood were taken between 1 to 21 days after hatching. antibodies (m. gallisepticum) responsible for both rapid serum agglutination (rsa) and haemagglutination inhibition were detected in the sera of progeny of infected hens, but these declined until they were undetectable by 18 days of age. by 4 days after hatching only approximately 65% of the birds were positive ...197718770325
incidence of pasteurella haemolytica in the respiratory tract of apparently healthy chickens and chickens with infectious bronchitis. characterisation of 213 strains.the tracheal flora of healthy chickens consisted mainly of gram-positive microorganisms. a shift to a predominantly gram-negative flora, mainly due to escherichia, was observed in chickens with respiratory symptoms caused by infectious bronchitis. most of the chickens in which e. coli formed a predominant part of the tracheal flora also showed a positive serological reaction to mycoplasma gallisepticum. a raised incidence of pasteurella haemolytica with increase in age was noted both with regard ...197718770338
serological studies on flocks showing depressed egg production.a serological investigation was undertaken of flocks with depressed egg production. no obvious correlation was found between antibody to adenovirus, infectious bronchitis virus or infectious bursal disease virus and this syndrome. no antibody was detected to newcastle disease virus, mycoplasma gallisepticum or in most cases to mycoplasma synoviae. a relationship was found between the development of antibody to a haemagglutinating virus, 127, and depressed egg production. a retrospective survey o ...197718770349
the response of the harderian gland of the fowl to antigen given by the ocular route. ii. antibody production.after ocular administration to young chickens of sheep erythrocytes (srbc), newcastle disease virus (ndv), infectious bronchitis virus (ibv) or mycoplasma gallisepticum, homologous antibody was detected in serum and in saline extracts of harderian glands. parenteral immunisation with srbc or ndv stimulated moderately high serum antibody titres but did not evoke a measurable antibody response by the harderian gland.197918770464
comparative efficiency of some rapid agglutination antigens for mycoplasma gallisepticum infection.varying compositions of growth media for mycoplasma galli-septicum were used in attempts to produce rapid slide agglutination antigens of high yield and improved specificity. some of the media barely supported growth, others yielded antigen no better than that from conventional media. two media gave good results. one was a conventional medium with horse serum replaced by foetal calf serum. the other was a conventional medium containing 10% horse serum, but at high ph (8.4). when compared with fo ...197418777264
[differentiation of haemophilus strains isolated from chickens. iii. pathogenicity tests in chickens].pathogenicity tests of 6 isolates of the haemophilus-group i (h. paragallinarum) and 8 isolates of the haemophilus-group ii isolated from chickens in the federal german republic and one strain of h. parainfluenzae isolated from man were carried out in 6-week old spf-chickens. infectious coryza (coryza contagiosa gallinarum) could be produced in chickens with all strains of group i after experimental inoculation and by contact exposure. at necropsy 3 weeks post inoculation (p.i.) organisms of gro ...197518777310
the rearing and maintenance of breeding chickens in isolators: 1. glass fibre isolators.a method of 'rearing and maintaining chickens from day old to 80 weeks of age free from infectious bronchitis, newcastle disease, infectious avian encephalomyelitis, celo and gal viruses, lymphoid leukosis, marek's disease, mycoplasma gallisepticum, salmonella pullorum and other salmonella spp., staphylococcus aureus, eimeria spp. and helminths is described. the advantages of glass fibre isolators each with its own ventilation system are outlined.197218777370
effects of prelay 6/85-strain mycoplasma gallisepticum inoculation alone or in conjunction with the inoculation of f-strain mycoplasma gallisepticum during lay on the blood characteristics of commercial egg-laying hens.the effects of 6/85-strain mycoplasma gallisepticum (6/85mg) inoculation alone or in conjunction with f-strain m. gallisepticum (fmg) overlays and their timing on the blood characteristics of commercial egg-laying hens were investigated. control birds received sham inoculations at 10 wk of age. birds in a second treatment group were inoculated with 6/85mg at 10 wk of age, those in a third treatment group were inoculated with 6/85mg at 10 wk followed by an overlay inoculation of fmg at 22 wk, and ...200818809862
circadian serum concentrations of tylosin in broilers after feed or water medication.1. because tylosin is a time-dependent antibacterial agent, and because feeding and drinking of broilers decreases in late afternoon and ceases in the dark, it was hypothesised that serum concentrations of this drug are greatly reduced during the dark period. 2. the trial was carried out in a commercial poultry house, under standard broiler husbandry conditions, with food and water withdrawn from 22:00 until 07:00 h next morning and exposed to a natural light cycle of 13l:11d. 3. broilers were g ...200818836909
adaptation of mycoplasmas to adverse growth conditions: morphology, ultrastructure, and genome expression of mycoplasma gallisepticum s6 cells. 200818853779
control of avian mycoplasma infections in commercial poultry.control of pathogenic avian mycoplasmas can consist of one of three general approaches: maintaining flocks free of infection, medication, or vaccination. maintaining flocks free of pathogenic mycoplasmas consists of maintaining replacements from mycoplasma-free sources in a single-age, all-in all-out management system. good biosecurity and an effective monitoring system are necessary aspects of this program. medication can be very useful in preventing clinical signs and lesions, as well as econo ...200818939621
differentiation of mycoplasma gallisepticum vaccine strains ts-11 and 6/85 from commonly used mycoplasma gallisepticum challenge strains by pcr.mycoplasma gallisepticum (mg) is an important avian pathogen causing significant economic losses within the poultry industry. in an effort to develop tools to aid in mg research and diagnostics, we have compared sequences of the attenuated mg vaccine strain ts-11 to those of commonly used pathogenic challenge strains in search of a simple means of differentiation. via gapa sequence alignments and comparisons, we have identified and designed primers facilitating strain differentiation. when appli ...200818939641
atomic force microscopy investigation of dna extracted from the vegetative forms and the viable but nonculturable forms of mycoplasma gallisepticum s6.recent studies show that mycoplasmas have various programs of life. this means that changes in morphology and genome expression may occur once the environment of these microorganisms becomes extremely altered. in this article, we report on changes in the dna molecule obtained from the vegetative forms and the viable but nonculturable (vbnc) forms of mycoplasma gallisepticum s6. atomic force microscopy studies show that the above-mentioned forms of the mycoplasma have different values of dna para ...200818979050
comparative infectiousness of three passerine bird species after experimental inoculation with mycoplasma gallisepticum.mycoplasma gallisepticum has been isolated from various species of free-living birds, and we therefore tested the hypothesis that bird species other than the main host, the house finch (carpodacus mexicanus), could play a role in the epidemiology of the infection. we compared the disease course in the house finch, american goldfinch (carduelis tristis) and house sparrow (passer domesticus) after inoculation into the conjunctival sac with m. gallisepticum, and also the degree to which the three s ...200819023761
compatibility of a combination of tiamulin and chlortetracycline with salinomycin in feed during a pulsed medication program coadministration in an earlier study, the continuous medication of broiler feed with a combination of tiamulin (tia; 20 mg/kg), chlortetracycline (ctc; 60 mg/kg), and the ionophore anticoccidial salinomycin (sal; 60 mg/kg) caused an initial increase in bw and feed efficiency (fe; g of weight gain/kg of feed intake). however, as doses increased to combinations of 30 mg/kg of tia and 90 mg/kg of ctc or 50 mg/kg of tia and 150 mg/kg of ctc, there was a dose-related reduction in growth rate and fe. this was thought ...200819038809
diseases of backyard turkeys in the mexican tropics.with the purpose of identifying the causes of disease and death in backyard turkeys, 768 interviews with growers were carried out in communities of the coastal region of oaxaca, mexico. later, a clinical sanitary evaluation was performed on five randomly selected turkeys of different age and sex. the laboratory tests included: necropsy for clinical diagnosis of diseases and for a histopathological examination of tissues with macroscopic lesions to identify microscopic lesions; hemagglutination i ...200819120252
[adaptation of mycoplasma gallisepticum to unfavorable growth conditions: changes in morphological and physiological characteristics].adaptation of mycoplasma gallisepticum to unfavorable growth conditions results in altered morphological and physiological characteristics of the cells. m. gallisepticum populations in a complete nutrient medium contain pear-shaped vegetative cells (d approximately 0.3 microm; l approximately 0.8 microm) with pronounced polar and cytoskeleton-like structures. such mycoplasma cells are able to induce damage in a bacterial genome, causing an sos response of the test strain (escherichia coli pq37). ...200819137716
backyard chicken flocks pose a disease risk for neotropic birds in costa rica.pathogens of free-ranging chickens create a risk of disease for wild birds, some of which migrate to the united states, as well as potential economic losses for resource-poor farmers. free-roaming backyard chickens are commonly kept in shade-grown coffee plantations, habitats that attract large numbers of wild birds. the husbandry and pathogen prevalence of backyard chicken flocks in san luis, costa rica, were investigated. based on serologic evidence, newcastle disease virus, infectious laryngo ...200819166045
molecular characterization and typing of enrofloxacin-resistant clinical isolates of mycoplasma gallisepticum.emergence of resistance to fluoroquinolones is mainly due to chromosomal mutations in genes encoding the subunits of the drug's target enzymes, dna gyrase and topoisomerase iv, which are essential for dna replication. the quinolone resistance-determining regions (qrdrs) of these genes were characterized in 25 mycoplasma gallisepticum strains isolated from commercial poultry flocks during 1997-2007, which exhibited different levels of susceptibility to fluoroquinolones. all enrofloxacin-resistant ...200819166064
facial cellulitis induced in chickens by mycoplasma gallisepticum bacterin and its treatment.ten-to-14-day-old replacement chickens were vaccinated subcutaneously in the neck with a mycoplasma gallisepticum bacterin. a few days later, 40% of the flock developed cellulitis of the head. birds were submitted for diagnostic investigation between 4 and 6 wk of age. histology revealed lesions in the subcutis consistent with oil-emulsified vaccine/bacterin reaction. no significant bacteria were isolated from the lesions. birds were treated with 1 mg of methyl prednisol acetate intramuscularly. ...200819166067
protective effect of two mycoplasma gallisepticum protein fractions affinity purified with monoclonal antibodies.two protein fractions of mycoplasma gallisepticum (mg) were affinity purified with monoclonal antibodies a3 and b3, and tested for protective capacity in chickens. one fraction, designated mgp1, appeared as a doublet of 64 and 62kda bands in sodium dodecyl sulphate-polyacrylamide gel electrophoresis gels, while mgp2 consisted of five polypeptides (64, 56, 47, 45 and 43 kda). the molecular mass, haemagglutination activity and matching amino acid sequence of mgp1 suggest that it is identical to pm ...200019184824
mycoplasmas and respiratory disease in pheasants and partridges.pheasants and partridges with signs of upper respiratory disease were cultured for mycoplasmas and were also examined for mycoplasma gallisepticum and mycoplasma synoviae using commercial polymerase chain reaction (pcr) kits. sixty-two incidents of disease were investigated in pheasants and 12 in partridges. m. gallisepticum was detected by culture in only four and three incidents in pheasants and partridges, respectively, but with pcr a further 15 m. gallisepticum-positive incidents were detect ...200119184924
secreted sialidase activity of canine mycoplasmas.through a survey of the phylogenetic distribution of sialidase among mycoplasmas, we detected activity secreted by the type strains of 3 of 11 species frequently or first isolated from dogs. the specific activity of washed cells of the type strains of mycoplasma canis, mycoplasma cynos, and mycoplasma molare ranged from 5.2+/-0.8 x 10(-6) to 1.1+/-0.3 x 10(-5) enzymatic units per colony-forming unit (u/cfu). cells of m. molare strain h542(t) had twice the specific activity (p<0.05) of m. canis s ...200919201110
effects of 6/85-strain mycoplasma gallisepticum vaccination 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 reproductive and digestive organs of commercial egg-laying hens.two trials were conducted to determine the effects of a prelay 6/85-strain mycoplasma gallisepticum (6/85mg) vaccination alone or in conjunction with time-specific f-strain m. gallisepticum (fmg) inoculation overlays on the gross reproductive and digestive organ characteristics of commercial egg-laying hens. in each trial, the following 4 treatments were applied: 1) sham vaccination at 10 wk of age; 2) vaccination of 6/85mg at 10 wk; 3) 6/85mg at 10 wk overlaid by fmg inoculation at 22 wk; and 4 ...200919211526
Displaying items 901 - 1000 of 1254