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dietary poultry fat, phytase, and 25-hydroxycholecalciferol influence the digestive and reproductive organ characteristics of commercial layers inoculated before or at the onset of lay with f-strain mycoplasma gallisepticum.effects of 2 supplemental concentrations of dietary poultry fat (pf) and the combination of pf, phytase (phy), and 25-hydroxycholecalciferol [25(oh)d] on the gross digestive and reproductive organ characteristics of commercial layers inoculated with f-strain mycoplasma gallisepticum (fmg) were investigated in 2 trials. sham and fmg inoculations were administered at 12 wk (before lay) or 22 wk (onset of lay), dietary treatments [basal control diet (bcd); bcd with 0.75% supplemental pf (lpfd); bcd ...201121406365
seroprevalence of salmonella and mycoplasma infection in backyard chickens in the state of entre rios in argentina.the present work was conducted to study the seroprevalence of salmonella, mycoplasma gallisepticum (mg), and mycoplasma synoviae (ms) infection in backyard chickens located in entre ríos, argentina, over 3 periods of time. a total of 2,441 sera samples were collected from backyard chickens belonging to 256 family farms in 16 counties in the state of entre ríos from january to may 2003 (first period), december 2004 to april 2005 (second period), and october 2006 to may 2007 (third period). the pr ...201121406358
change in antimicrobial susceptibility of mycoplasma gallisepticum field isolates.this study compares the antimicrobial susceptibility over time between two groups of mycoplasma gallisepticum (mg) isolates from the same geographical area. minimum inhibitory concentration of 13 antimicrobials was determined against two groups of mg isolates from chickens. group 1 strains (n=22) were isolated in 2004-2005 while group 2 strains (n=7) were isolated in 2007-2008. minimum inhibitory concentration 50 for group 1 versus group 2 was 4/4, 0.5/0.5, ôëñ 0.031/ôëñ 64, ôëñ 0.031/2, ôëñ 0.0 ...201121382675
development and immunogenicity of recombinant gapa(+) mycoplasma gallisepticum vaccine strain ts-11 expressing infectious bronchitis virus-s1 glycoprotein and chicken interleukin-6.mycoplasma gallisepticum (mg) is a major pathogen of poultry that causes chronic respiratory disease in chickens and infectious sinusitis in turkeys. a live attenuated vaccine, ts-11, has been used for the control of mg in several countries. the efficacy of this vaccine is highly dose dependent and the flock antibody response is weak. to improve the functionality of the vaccine and investigate its potential as a delivery vector for foreign antigens and immunomodulatory proteins, we developed a d ...201121354248
analysis of the 16s to 23s rrna intergenic spacer region of mycoplasma synoviae field strains.mycoplasma synoviae has been associated with economic loss in the chicken and turkey industries. the molecular characterization of m. synoviae at strain level allows the analysis of relationships between strains that may be valuable in epidemiological investigations. in the present study, the intergenic spacer region (isr) between the 16s and 23s rrna genes was examined to see whether useful information about strains could be derived. m. synoviae has two copies of this region, which may not be e ...201121331951
eye surface area and dosage rates for spray vaccination.spray application of mycoplasma gallisepticum (mg) vaccines is a labor- and time-saving means of mass vaccination of layer chickens. recent assessment of spray characteristics of nozzles commonly used to apply mg vaccine in layer chicken operations has shown that the amount of respirable droplets (< 5 microm) is negligible. topical application of vaccine onto the eye surface has been suggested as a route of vaccination, but no estimates of vaccine load delivered via spray application were found ...201021313856
gapa+ mycoplasma gallisepticum ts-11 has improved vaccine characteristics.mycoplasma gallisepticum (mg) is an important poultry pathogen that causes respiratory disease and loss of production worldwide, and is currently controlled with live attenuated vaccines. these vaccines have limitations as they vary in their pathogenicity, the protection afforded and their transmissibility, but have been shown to effectively reduce losses associated with challenge in the field. a live attenuated vaccine, ts-11, has been used for the control of m. gallisepticum in several countri ...201121310786
comparison of blood values and health status of floreana mockingbirds (mimus trifasciatus) on the islands of champion and gardner-by-floreana, galápagos islands.the floreana mockingbird (mimus trifasciatus) is one of the rarest bird species in the world, with an estimated 550 individuals remaining on two rocky islets off the coast of floreana, galápagos, ecuador, from which the main population was extirpated more than 100 yr ago. because they have been listed in critical danger of extinction, a plan to reintroduce this species to floreana has been initiated. determining the health status of the source mockingbird populations is a top priority within the ...201121270000
effects of single and combined mycoplasma gallisepticum vaccinations on blood electrolytes and acid-base balance in commercial egg-laying hens.a previous study from our laboratory on f-strain mycoplasma gallisepticum-inoculated layers showed a significant increase in arterial partial pressure of oxygen (po(2)), which is generally associated with an oxygen-dependent improvement in tissue oxygenation. the aim of this study was to determine whether a killed (bacterin) and live ts-11-strain m. gallisepticum (ts-11-mg) vaccine treatment combination could further enhance the arterial po(2) levels in layer chickens. the experiment was conduct ...201121248332
proteomic characterization of mycoplasma gallisepticum nanoforming.the goal of this work was to create a model for the long persistence of mycoplasma gallisepticum in depleted medium and under low growth temperature followed by proteomic study of the model. nanoforms and revertants for m. gallisepticum were obtained. proteomic maps were produced for different stages of the formation of nanoforms and revertants. it is shown that proteins responsible for essential cellular processes of glycolysis, translation elongation, and dnak chaperone involved in the stabili ...201021166642
bi-antigenic immunoassay models based on the recombinant pvpa proteins for mycoplasma gallisepticum diagnosis in chickens.the present study aimed to produce the relatively conserved central fragment of the mycoplasma gallisepticum pvpa cytadhesin as recombinant antigen and to determine its species-specific diagnostic potential in comparison with the full-length recombinant rpvpa336 protein. for this purpose, a recombinant protein (rpvpa134) consisting of 134 amino acids with apparent molecular mass of 27 kd was produced and highly purified. the rpvpa134 protein was composed of the amino acid residues at positions 1 ...201021088174
construction of mini-tn4001 transposon vector for mycoplasma gallisepticum.the detailed genetic analysis of mycoplasmas has long been hampered by the lack of appropriate tools for genetic manipulation. in this study, the transposon vector, mini-tn4001tetm, was constructed containing the tnp gene, encoding a transposase gene in staphylococcus aureus, two copies of the is256 inverted repeat sequence (inner and outer) and the tetm gene, from the enterococcus faecalis tn916 transposon, conferring resistance to tetracycline. this vector was electro-transformed into mycoplas ...201021046326
mycoplasma gallisepticum and mycoplasma synoviae express a cysteine protease cysp, which can cleave chicken igg into fab and fc.major poultry pathogens m. gallisepticum and m. synoviae share a gene encoding a putative cysteine protease cysp similar to papain cysteine protease (c1a subfamily). comparison of the cysp gene sequences of 18 m. synoviae and 10 m. gallisepticum strains sequenced in this study showed polymorphisms, including deletions. seven m. synoviae strains, including the type strain wvu 1853, had a 39&emsp14;bp deletion in the 3' end of the cysp gene. in the same cysp region, all m. gallisepticum strains sh ...201020966088
a chronicle of serologic response in commercial layer chickens to vaccination with commercial f strain mycoplasma gallisepticum vaccine.vaccination of multi-age layer operations, wherein one million plus commercial layer chickens are housed, has been spurious until the development of a self-propelled, constant-speed spray vaccinator. still, even with its use, live mycoplasma gallisepticum (mg) vaccinations have been questionable in terms of seroconversion. using the vaccinator as a research tool over the past 5 yr, factors have been elucidated which impact seroconversion to one live mg vaccine in particular, the f strain of mg ( ...201020945798
influence of supplemental dietary poultry fat, phytase, and 25-hydroxycholecalciferol on the egg characteristics of commercial layers inoculated before or at the onset of lay with f-strain mycoplasma gallisepticum.the effects of supplemental dietary poultry fat (pf), phytase (phy), and 25-hydroxycholecalciferol (d3) on the egg characteristics of commercial layers inoculated with f-strain mycoplasma gallisepticum (fmg) were investigated in 2 trials. sham and fmg inoculations were administered at 12 (before lay) and 22 (onset of lay) wk and 4 dietary treatments [basal control diet (bcd); bcd with 0.75% supplemental pf; bcd with 1.50% supplemental pf; bcd with 1.50% supplemental pf, 0.013% phy, and 0.025% d3 ...201020852097
adaptation of mycoplasmas to adverse environments: phytopathogenicity and peculiarities of protein expression of vegetative and nonculturable forms of mycoplasma gallisepticum s6 cells. 200920848917
mycoplasma sturni from a california house finch with conjunctivitis did not cause disease in experimentally infected house finches.mycoplasma gallisepticum 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. a key feature for the successful study of natural and experimental disease has been the apparent, very-high correlation between characteristic eye lesions and m. gallisepticum. mycoplasma sturni was originally isolated from an adult european starling (sturnus vulgaris) with bilateral conjunc ...201020688712
an adhesion molecule-based colloidal gold immunochromatography assay strip for rapidly and specifically detecting chicken antibodies against mycoplasma gallisepticum.the fragment of the vlha1.2 gene was cloned from a mycoplasma gallisepticum (mg) dna library by serial pcrs after the same-sense mutagenesis of three tga codons encoding tryptophan (trp). following transforming the generated plasmid of pkg-vlha1.2, the recombinant vlha1.2-gst fusion protein of 92kda was induced and recognized by anti-mg sera. after gst-affinity chromatographic purification, the vlha-based colloidal gold immunochromatography assay (gica) strips were generated. the gica strips spe ...201120630551
genetic diversity of mycoplasma gallisepticum field isolates using partial sequencing of the pvpa gene fragment in russia.the genetic diversity of the pvpa gene of mycoplasma gallisepticum (mg) samples originating from commercial chickens was investigated. in the present study, we evaluated the genetic variability of 26 field samples of mg detected in commercial chickens and turkeys from 18 regions of russia and compared them to the reference strains of mg available in genbank. genetic variability was evaluated by partial nucleotide sequencing of the pvpa gene, which encodes a putative cytadhesin protein. compariso ...201020608536
common garden experiment reveals pathogen isolate but no host genetic diversity effect on the dynamics of an emerging wildlife disease.host genetic diversity can mediate pathogen resistance within and among populations. here we test whether the lower prevalence of mycoplasmal conjunctivitis in native north american house finch populations results from greater resistance to the causative agent, mycoplasma gallisepticum (mg), than introduced, recently-bottlenecked populations that lack genetic diversity. in a common garden experiment, we challenged wild-caught western (native) and eastern (introduced) north american finches with ...201020561136
identification of lipoprotein msla as a neoteric virulence factor of mycoplasma gallisepticum.many lipoproteins are expressed on the surfaces of mycoplasmas, and some have been implicated as playing roles in pathogenesis. family 2 lipoproteins of mycoplasma pneumoniae have a conserved "mycoplasma lipoprotein x" central domain and a "mycoplasma lipoprotein 10" c-terminal domain and are differentially expressed in response to environmental conditions. homologues of family 2 lipoproteins are mycoplasma specific and include the lipoprotein of mycoplasma gallisepticum, encoded by the mga0674 ...201020515935
mutations in 23s rrna gene associated with decreased susceptibility to tiamulin and valnemulin in mycoplasma gallisepticum.mycoplasma gallisepticum is a major etiological agent of chronic respiratory disease (crd) in chickens and sinusitis in turkeys. the pleuromutilin antibiotics tiamulin and valnemulin are currently used in the treatment of m. gallisepticum infection. we studied the in vitro development of pleuromutilin resistance in m. gallisepticum and investigated the molecular mechanisms involved in this process. pleuromutilin-resistant mutants were selected by serial passages of m. gallisepticum strains pg31 ...201020487023
mycoplasma gallisepticum: an emerging challenge to the poultry industry in egypt.in this study, the authors examined the technical performance of culture methodology using specific media: mycoplasma isolation media of pleuropneumonia-like organisms (pplo) broth and pplo agar. digitonin sensitivity, growth inhibition, the serum plate agglutination test, a commercially available enzyme-linked immunosorbent assay (elisa) and a commercially available simplex polymerase chain reaction (pcr) test were used to detect mycoplasma gallisepticum infections in samples collected from the ...200920462158
a safety assessment of a fowlpox-vectored mycoplasma gallisepticum vaccine in chickens.a recombinant fowlpox virus vaccine expressing key protective mycoplasma gallisepticum antigens could facilitate in the prevention both of fowlpox virus and m. gallisepticum infections. vectormune fp-mg vaccine, a recombinant fowlpox virus expressing both m. gallisepticum 40k and mgc genes, was assessed for its safety in 8-wk-old specific-pathogen-free white leghorn chickens. the vaccine virus was serially passaged 5 times by wing-web inoculation. based on the postinoculation clinical observatio ...201020460677
development of a duplex real-time taqman pcr assay with an internal control for the detection of mycoplasma gallisepticum and mycoplasma synoviae in clinical samples from commercial and backyard poultry.in this study, we report the development and validation of a duplex real-time polymerase chain reaction (pcr) assay with an internal control using taqman-labelled probes for the detection of mycoplasma gallisepticum and mycoplasma synoviae (duplex mgms pcr). the mgms pcr was highly specific with a sensitivity of 7 and 1 colony-forming units/ml for m. gallisepticum and m. synoviae, respectively, using dilution of pure culture that corresponds to 34 and 29 dna copies per reaction. validation of th ...201020390544
systematic search for putative new domain families in mycoplasma gallisepticum genome.abstract:201020384986
influence of supplemental dietary poultry fat, phytase, and 25-hydroxycholecalciferol on the performance of commercial layers inoculated before or at the onset of lay with f-strain mycoplasma gallisepticum.the effects of 2 levels of supplemental dietary poultry fat (pf) and the combination of pf, phytase (phy), and 25-hydroxycholecalciferol (d(3)) on the performance of commercial layers inoculated with f-strain mycoplasma gallisepticum (fmg) were investigated in 2 trials. sham and fmg inoculations were administered at 12 (before lay) and 22 (early in lay) wk and dietary treatments [basal control diet (bcd), bcd with 0.75% supplemental pf, bcd with 1.50% supplemental pf, and bcd with 1.50% suppleme ...201020371842
protective immune response of mycoplasma gallisepticum vaccines in poultry.through a controlled vaccination study with artificial challenge, the present study was designed to evaluate the protective value of formalin, saponin or binary ethyleneimine inactivated mycoplasma gallisepticum adjuvanted bacterins, in comparison with the efficacy of the live mycoplasma gallisepticum "f" strain vaccine. protective values of tested vaccines were compared by measuring antibody titers in sera of chicken at different intervals post vaccination by enzyme linked immunosorbent assay ( ...200720306661
evaluation of mycoplasma inactivation during production of biologics: egg-based viral vaccines as a model.although mycoplasmas are generally considered to be harmless commensals, some mycoplasma species are able to cause infections in pediatric, geriatric, or immunocompromised patients. thus, accidental contamination of biologics with mycoplasmas represents a potential risk for the health of individuals who receive cell-derived biological and pharmaceutical products. to assess the efficiency of inactivation of mycoplasmas by the agents used in the manufacture of egg-derived influenza vaccines, we ca ...201020228111
effects of vaccination with f-strain mycoplasma gallisepticum on egg production and quality parameters of commercial layer hens previously vaccinated with 6/85-strain mycoplasma gallisepticum.this study was conducted to determine the effect of overlaying (revaccinating) f-strain mycoplasma gallisepticum at 22 or 45 wk of age on commercial leghorn hens previously vaccinated with 6/85-strain m. gallisepticum at 10 wk of age. the treatment groups included unvaccinated hens (group 1), hens receiving 6/85-strain m. gallisepticum only (group 2), and hens receiving 6/85-strain m. gallisepticum followed by f-strain m. gallisepticum at either 22 (group 3) or 45 (group 4) wk of age. there was ...201020181866
animal behaviour: an ill wind for finches. 201020164914
sickness behaviour acting as an evolutionary trap? male house finches preferentially feed near diseased conspecifics.host behaviour towards infectious conspecifics is a crucial yet overlooked component of pathogen dynamics. selection is expected to favour individuals who can recognize and avoid infected conspecifics in order to reduce their own risk of infection. however, evidence is scarce and limited to species employing chemical cues. here, we experimentally examine whether healthy captive house finches (carpodacus mexicanus) preferentially forage near a same-sex, healthy conspecific versus one infected wit ...201020164082
real-time pcr culture and serology for the diagnosis of mycoplasma gallisepticum in chicken breeder flocks.this study aimed to compare a real-time pcr (rpcr) test with improved detection limit to serology and culture for the detection of mycoplasma gallisepticum (mg) infection in chicken breeder flocks. six hundred and forty-six blood and tracheal swab samples belonging to 31 grandparent chicken breeder flocks were tested by rpcr. the detection limit of rpcr was 0.9 pg microl(-1), with pure mg s6 strain dna and 100 colony forming units (cfus) ml(-1), where both pure culture and tracheal swabs were ar ...201020149561
spatial variation in an avian host community: implications for disease dynamics.because many pathogens can infect multiple host species within a community, disease dynamics in a focal host species can be affected by the composition of the host community. we examine the extent to which spatial variation in species' abundances in an avian host community may contribute to geographically varying prevalence of a recently emerged wildlife pathogen. mycoplasma gallisepticum is a pathogen novel to songbirds that has caused substantial mortality in house finches (carpodacus mexicanu ...201020130959
comparative genomic analyses of attenuated strains of mycoplasma gallisepticum.mycoplasma gallisepticum is a significant respiratory and reproductive pathogen of domestic poultry. while the complete genomic sequence of the virulent, low-passage m. gallisepticum strain r (r(low)) has been reported, genomic determinants responsible for differences in virulence and host range remain to be completely identified. here, we utilize genome sequencing and microarray-based comparative genomic data to identify these genomic determinants of virulence and to elucidate genomic variabili ...201020123709
characteristics of a very virulent infectious bursal disease virus from california.an outbreak of infectious bursal disease (ibd) in two california layer flocks resulted in the isolation of two infectious bursal disease viruses designated ra and rb. increased mortality plus gross and histopathology in the layer flocks suggested ra and rb could be very virulent infectious bursal disease virus (vvibdv). preliminary studies indicated that high mortality resulted when bursa homogenates from the layer farms were used to inoculate specific-pathogen-free (spf) chicks. in addition, ra ...200920095162
influence of supplemental dietary poultry fat on the digestive and reproductive organ characteristics of commercial layers inoculated before or at the onset of lay with f-strain mycoplasma gallisepticum.effects of f-strain mycoplasma gallisepticum (fmg) inoculation and 1.5% supplemental dietary poultry fat (pf) on the digestive and reproductive organ characteristics of commercial layers at 58 wk of age were investigated. sham and fmg inoculations were administered at 12 (before lay) and 22 (early in lay) wk of age, and dietary treatments (basal control diets and basal control diets with pf) were initiated at 20 wk of age. supplemental pf increased bw and decreased isthmal length relative to tot ...201020075276
differentiation of mycoplasma gallisepticum strains using pcr and high-resolution melting curve analysis.mycoplasma gallisepticum (mg) is an economically important pathogen of poultry worldwide, causing chronic respiratory disease in chickens and turkeys. differentiation of mg strains is critical, especially in countries where poultry flocks are vaccinated with live vaccines. in this study, oligonucleotide primers were designed based on a region preceding the trinucleotide repeat of a member of the vlha gene family, and amplicons of 145-352 bp were generated from cultures of 10 different mg strains ...201020035007
effect of dosage and vaccination route on transmission of a live attenuated mycoplasma gallisepticum vaccine: a broiler model.mycoplasma gallisepticum (mg) is an economically significant pathogen of poultry species. among the table egg sector of the poultry industry, live attenuated strains of mg are commonly used to limit production losses associated with mg-induced disease. these vaccines, however, may be problematic to broiler- and turkey-related industries because of associated virulence; therefore, an understanding of the transmissibility of the live mg vaccines is of particular importance. in the present study, a ...200919848082
[adaptation of mycoplasmas to stressful factors: nucleotide sequences nonregistered in vegetative forms of m. galisepticum s6 cells are revealed in nonculturable forms of the mycoplasma].adaptation of m. gallisepticum s6 to unfavorable environmental conditions is connected with transformation of the vegetative forms of the mycoplasma cells to the viable but non-culturable (vbnc) forms. the vegetative forms and the vbnc forms differ in the spectrum of the pcr-products that was forming due to amplification of the nucleotide sequence of the pvpa-gene coding the able cytoadhesion protein. as to vegetative forms of the mycoplasma the only amplicon, containing one open reading frame ( ...200919807027
phytopathogenicity of avian mycoplasma mycoplasma gallisepticum s6: morphologic and ultracytostructural changes in plants infected with the vegetative forms and the viable but nonculturable forms of the bacterium.the data obtained in this study proved that mycoplasma gallisepticum s6 known as avian pathogen had a phytopathogenic potential. the vegetative forms and the viable but nonculturable (vbnc) forms of this mycoplasma could infect the plants via an assemblage of rootlets, invade different tissues, persist there and cause destructive events characteristic to phytomycoplasmoses. in comparison with the vegetative forms, the vbnc forms induced more prominent destructive changes. this phenomenon might b ...201019716689
influence of supplemental dietary poultry fat on the yolk characteristics of commercial layers inoculated before or at the onset of lay with f-strain mycoplasma gallisepticum.effects of f-strain mycoplasma gallisepticum (fmg) inoculation and 1.5% supplemental dietary poultry fat (pf) on the egg yolk characteristics of commercial layers at 24, 34, 44, 50, and 58 wk of age were investigated. sham and fmg inoculations were administered at 12 and 22 wk of age and dietary treatments (basal control and basal control with 1.5% supplemental pf) were initiated at 20 wk of age. yolk lipid concentration was reduced on wk 24 in birds that had been inoculated at 12 or 22 wk of ag ...200919687273
production of house finch (carpodacus mexicanus) iga specific anti-sera and its application in immunohistochemistry and in elisa for detection of mycoplasma gallisepticum-specific iga.the iga antibody response plays a vital role in mucosal immunity because it functions to neutralize pathogens at the mucosal surface and thus impedes attachment to underlying tissues. although the importance of iga in the mucosal immunity of galliform birds has been established, studies examining iga-based immunity in passerine birds are lacking, perhaps due in part to the absence of reagents that can detect passerine iga. a 469 base pair region of the house finch (carpodacus mexicanus) iga heav ...200919581004
influence of supplemental dietary poultry fat on the performance of commercial layers inoculated before or at the onset of lay with f-strain mycoplasma gallisepticum.the effects of f-strain mycoplasma gallisepticum (fmg) inoculation and 1.5% supplemental dietary poultry fat (pf) on the performance of commercial layers between 20 and 58 wk of age were investigated. sham and fmg inoculations were administered at 12 (before lay) and 22 (early in lay) wk and dietary treatments (basal control diets and basal control diets with 1.5% supplemental pf) were initiated at 20 wk of age. mortality at wk 47 and 53 was greatest in birds inoculated with fmg at 22 wk. feed c ...200919531705
[prevalence of mycoplasmas in commercial layer flocks during laying period].within this study's range, laying hens from different housing systems were investigated on prevalence of mycoplasma sp. for the duration of one laying period, with an emphasis on the two clinically relevant species m. synoviae and m. gallisepticum. tracheal swabs were analysed for mycoplasms by genus- and species-specific amplification after dna extraction. of 919 collected tracheal swabs, 84% were positive for the genus-specific test, while 75% turned out positive for m. synoviae. mycoplasms we ...200919517932
molecular variability of dr-1 and dr-2 within the pvpa gene in mycoplasma gallisepticum isolates.a total of 15 mycoplasma gallisepticum (mg) isolates from chinese poultry farms and three reference strains (s6, bg44t, and f36) were characterized by nested polymerase chain reaction and sequence analysis for two identical and directly repeated sequences, dr-1 and dr-2, within the putative cytadhesin pvpa gene. the molecular variation patterns of the pvpa genes among the 15 mg isolates were identical to the reference strains s6 and bg44t, that is, a 60 bp deletion in dr-1 and dr-2 and repetitio ...200919432015
the development of diagnostic real-time taqman pcrs for the four pathogenic avian mycoplasmas.four avian mycoplasmas are commonly recognized as poultry pathogens: mycoplasma gallisepticum (mg), mycoplasma synoviae (ms), mycoplasma meleagridis (mm), and mycoplasma iowae (mi). the avian mycoplasmas are associated with respiratory disease, synovitis and arthritis, poor performance, skeletal deformities, and embryo mortality. three main approaches are used for the diagnosis of avian mycoplasmosis: isolation and identification, detection of antibodies, and molecular detection of the organism' ...200919432011
development of a real-time polymerase chain reaction assay for the simultaneous detection of mycoplasma gallisepticum and mycoplasma synoviae under industry conditions.in this research we developed a real-time sybr green assay to detect both mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) in a single reaction. a total of 30,000 samples from broiler breeder flocks were screened using traditional serology (plate agglutination, enzyme-linked immunosorbent assay, hemagglutination inhibition) and polymerase chain reaction (pcr; traditional and real-time). it was determined that the real-time sybr green pcr assay developed in this research was more rapid ...200919432006
effects of time-specific f-strain mycoplasma gallisepticum inoculation overlays on prelay ts-11-strain m. gallisepticum vaccination on digestive and reproductive organ characteristics of commercial egg-laying hens.two trials were conducted to determine the effects of a prelay ts-11-strain mycoplasma gallisepticum (ts-11mg) vaccination alone or in conjunction with f-strain m. gallisepticum (fmg) inoculation overlays at 2 different age periods during lay on the digestive and reproductive organ characteristics of commercial egg-laying hens. in each trial, the following 4 treatments were utilized: sham vaccination at 10 wk of age, ts-11mg vaccination at 10 wk of age, ts-11mg at 10 wk of age overlaid by fmg in ...200919359686
effects of time-specific f-strain mycoplasma gallisepticum inoculation overlays on prelay ts-11-strain m. gallisepticum vaccination on blood characteristics of commercial laying hens.two trials were conducted to determine the effects of a prelay ts-11-strain mycoplasma gallisepticum (ts-11mg) vaccination alone or in combination with subsequent time-specific f-strain m. gallisepticum (fmg) inoculations on the blood characteristics of commercial laying hens. the following 4 treatments were utilized: 1) sham vaccination at 10 wk of age, 2) vaccination of ts-11mg at 10 wk, 3) ts-11mg at 10 wk overlaid by fmg inoculation at 22 wk, and 4) ts-11mg at 10 wk overlaid by fmg at 45 wk. ...200919359676
diversifying and stabilizing selection of sialidase and n-acetylneuraminate catabolism in mycoplasma synoviae.sialidase activity varies widely among strains and tends to correlate with strain virulence in the avian pathogen mycoplasma synoviae. to characterize the forms of selection acting on enzymes required for sialic acid scavenging and catabolism, the ratios of nonsynonymous (k(a)) to synonymous (k(s)) mutation frequency were calculated for codons in the sialidase gene of 16 strains of m. synoviae and for its nearly identical homolog in four strains of mycoplasma gallisepticum. the k(a)/k(s) (omega) ...200919329630
mycoplasma synoviae invades non-phagocytic chicken cells in vitro.mycoplasma synoviae and mycoplasma gallisepticum are major poultry pathogens, but their strains differ significantly in invasiveness and pathogenicity. recent studies have demonstrated that m. gallisepticum invades chicken erythrocytes (cer) and chicken embryonic fibroblasts. the aim of this study was to determine whether m. synoviae also invades chicken cells. using the gentamicin invasion assay, relative invasion frequency (rif) of four m. synoviae strains was determined for cer, chicken embry ...200919321273
cytoskeletal asymmetrical dumbbell structure of a gliding mycoplasma, mycoplasma gallisepticum, revealed by negative-staining electron microscopy.several mycoplasma species feature a membrane protrusion at a cell pole, and unknown mechanisms provide gliding motility in the direction of the pole defined by the protrusion. mycoplasma gallisepticum, an avian pathogen, is known to form a membrane protrusion composed of bleb and infrableb and to glide. here, we analyzed the gliding motility of m. gallisepticum cells in detail. they glided in the direction of the bleb at an average speed of 0.4 microm/s and remained attached around the bleb to ...200919286806
proteome of the bacterium mycoplasma gallisepticum.using modern proteomic assays, we have identified the products of gene expression and posttranslational modifications of proteins of the bacterium mycoplasma gallisepticum s6. combinations of different technologies of protein separation by electrophoresis and mass-spectrometric analysis gave us a total of 446 proteins, i.e. 61% of the annotated proteins of this microorganism. the pro-q diamond and pro-q emerald dye technology was used for fluorescent detection of ten phosphoproteins and two glyc ...200919267672
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
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
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
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
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
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
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
[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
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
compatibility of a combination of tiamulin and chlortetracycline with salinomycin in feed during a pulsed medication program coadministration in broilers.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
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
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
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
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
adaptation of mycoplasmas to adverse growth conditions: morphology, ultrastructure, and genome expression of mycoplasma gallisepticum s6 cells. 200818853779
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
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
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
[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
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
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
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
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
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
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
[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
[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
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
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
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
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
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
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
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
[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
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
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
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
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
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
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
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 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
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
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
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
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