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dynamics of a novel pathogen in an avian host: mycoplasmal conjunctivitis in house finches.in early 1994, a novel strain of mycoplasma gallisepticum (mg)--a poultry pathogen with a world-wide distribution--emerged in wild house finches and within 3 years had reached epidemic proportions across their eastern north american range. the ensuing epizootic resulted in a rapid decline of the host population coupled with considerable seasonal fluctuations in prevalence. to understand the dynamics of this disease system, a multi-disciplinary team composed of biologists, veterinarians, microbio ...200515777638
safety and efficacy of mycoplasma gallisepticum ts-11 vaccine for the protection of layer pullets against challenge with virulent m. gallisepticum r-strain.mycoplasma gallisepticum ts-11 vaccine was studied for its safety and protective ability in 49-day-old m. gallisepticum-free and mycoplasma synoviae-free commercial tetra sl layer chickens. sixty birds were distributed into four groups: 15 were unvaccinated but were challenged with m. gallisepticum r-strain, 15 were vaccinated by eye drop and then challenged with virulent m. gallisepticum r-strain 4 weeks post vaccination, 15 were designated as controls without vaccination and challenge, and 15 ...200516147571
comparison of culture, pcr, and different serologic tests for detection of mycoplasma gallisepticum and mycoplasma synoviae infections.in this study, the technical performance of culture, two commercially available polymerase chain reaction (pcr) tests, rapid plate agglutination (rpa) test, hemagglutination inhibition (hi) test, and eight commercially available enzyme-linked immunosorbent assays (elisas) were compared for the detection of avian mycoplasma infections from 3 days postinfection (d.p.i.) through 35 d.p.i. the tests were carried out on samples from specified pathogen-free layers that were infected at 66 wk of age wi ...200516094832
duplex pcr to differentiate between mycoplasma synoviae and mycoplasma gallisepticum on the basis of conserved species-specific sequences of their hemagglutinin genes.we developed a duplex pcr assay targeting the hemagglutinin multigene families, vlha and pmga, of mycoplasma synoviae and mycoplasma gallisepticum, respectively. the assay proved to be specific and sensitive enough to justify its use for the simultaneous detection of the two major avian mycoplasma species from field isolates.200515695715
differentiation of mycoplasma gallisepticum strains using amplified fragment length polymorphism and other dna-based typing methods.amplified fragment length polymorphism (aflp) was used to type 34 strains of mycoplasma gallisepticum (mg) including vaccine strains ts-11, 6/85, and f. using aflp, a total of 10 groups, with 30 distinguishable aflp typing profiles, were generated in the analysis. the aflp method was able to identify and differentiate both mg field strains from recent outbreaks and those that were epidemiologically related. the aflp procedure will provide assistance in identifying the sources of mycoplasma infec ...200515839411
an experimental model to quantify horizontal transmission of mycoplasma gallisepticum.before interventions to control horizontal transmission of mycoplasma gallisepticum can be tested, a suitable experimental model should be available. transmission dynamics in a flock can be quantified by two parameters: the average number of secondary cases infected by one typical infectious case (r0) and the number of new infections that occur due to one infectious animal per unit of time (beta). the transmission dynamics of m. gallisepticum have not been studied experimentally, so the aim of t ...200516147573
an acute inflammatory response alters bone homeostasis, body composition, and the humoral immune response of broiler chickens.to quantify the effects of an acute phase response in broilers, chicks were injected with 1 mg/kg escherichia coli lipopolysaccharide (lps) at 15 and 23 d. lipopolysaccharide injection increased feed/gain (p = 0.03), increased liver weight (p = 0.09), and decreased tibia calcium (p = 0.05) and breaking strength (p < 0.04) by d 28. in a second experiment, 3 d postinjection of chicks at d 31, lps decreased bw (p < 0.01), breast weight (p = 0.08), and tibia breaking strength (p = 0.05), and increas ...200515844811
carotenoid-based plumage coloration predicts resistance to a novel parasite in the house finch.the hamilton-zuk hypothesis proposes that the bright colours displayed by many species of birds serve as signals of individual resistance to parasites. despite the popularity of this hypothesis, only one previous study has tested whether plumage coloration predicts how individuals respond to a disease challenge. we inoculated 24 male house finches (carpodacus mexicanus) of variable plumage hue with a novel bacterial pathogen, mycoplasma gallicepticum (mg). we found no relationship between plumag ...200515558224
pigeon paramyxovirus: association with common avian pathogens in chickens and serologic survey in wild birds.pigeon paramyxovirus-1 (ppmv-1) was isolated from pigeons from east-central alabama and used in association with chicken anemia virus (cav), infectious bursal disease virus (ibdv), or finch mycoplasma gallisepticum (mg) in specific-pathogen-free chickens to assess dinical disease and pathology. ppmv-1 infection in all groups was conducted at day 10 of age via the ocular route. the low passage ppmv-1 isolate was inoculated into chickens in different groups at 10 days post-cav infection, 6 days po ...200515839419
evaluation and comparison of various pcr methods for detection of mycoplasma gallisepticum infection in chickens.four genetic mycoplasma gallisepticum (mg) polymerase chain reactions (pcrs) (16s rrna pcr, three newly developed pcr methods that target surface protein genes [mgc2, lp (nested) and gapa (nested)]) were compared for analytical specificity and sensitivity and for diagnostic sensitivity (se) and specificity of detection from tracheal swabs. the licensed mg dna test kit flock chek test (idexx, laboratories, inc., westbrook, me) was as well evaluated for the diagnostic specificity and sensitivity o ...200515839425
floor pen study to evaluate the serological response of broiler breeders after vaccination with ts-11 strain mycoplasma gallisepticum vaccine.to determine the mycoplasma gallisepticum (mg) rapid serum plate agglutination (rspa) test response of broiler breeders after ts-11 strain vaccination, 55 cobb pullets derived from a nonvaccinated, mg-negative, commercial, broiler breeder grandparent flock were monitored from 8 to 20 wk of age (over a 12-wk trial period). to evaluate the effect of lateral spread of the ts-11 vaccine strain on rspa test results from commingled and adjacently penned birds, treatment groups included (a) birds vacci ...200515839426
a self-propelled, constant-speed spray vaccinator for commercial layer chickens.vaccination of commercial layer chickens is labor intensive and often results in poor rates of seroconversion, which, in turn, generally correlate with decreased flock uniformity and performance. attempts to improve the vaccination process include numerous variations of individual shop-built vaccinators in use by the layer sector of the poultry industry. each of these vaccinators has limitations that contribute to poor vaccinations. major problems include the nonuniform speed of the applicator s ...200515839429
chemotaxis in mycoplasma gallisepticum.boyden-type chemotactic chambers were used to demonstrate that mycoplasma gallisepticum (mg) was capable of migrating into chemotactic membranes. scanning electron microscopy was used to confirm that mg could penetrate the membranes. to further demonstrate the invasive ability of mg, mg was deposited on the shell membranes of 9-day-old chicken embryos, and after 6 days of incubation, the presence of mg dna in the allantoic fluids was detected by polymerase chain reactions. these results indicate ...200515839430
genotyping of mycoplasma gallisepticum and m. synoviae by amplified fragment length polymorphism (aflp) analysis and digitalized random amplified polymorphic dna (rapd) analysis.mycoplasma gallisepticum (mg) and m. synoviae (ms) are the cause of considerable economic losses in the poultry industry. molecular differentiation of avian mycoplasma strains may be helpful in tracing infections and in the evaluation of implemented intervention strategies. amplified fragment length polymorphism (aflp) has shown to be a powerful typing technique but the application for poultry mycoplasma strains is very limited. the aim of this study was to evaluate the reproducibility and discr ...200516236471
transfer of maternal immunoglobulins and antibodies to mycoplasma gallisepticum and mycoplasma synoviae to the allantoic and amniotic fluid of chicken embryos.maternal antibodies can protect avian embryos against vertically transmitted pathogens during embryogenesis and also young birds after hatching. in contrast to the well-known transfer of maternal immunoglobulin (ig) g (also termed igy) from the yolk to embryonic blood, information about the transfer of iga, igg and igm from the egg albumen to the extra-embryonic fluids is very limited. in our study, iga, igg and igm to mycoplasma gallisepticum and mycoplasma synoviae were detected in oviduct was ...200516537160
key role of chlamydophila psittaci on belgian turkey farms in association with other respiratory pathogens.two hundred turkey sera from eight belgian and two french farms were tested for the presence of antibodies against avian pneumovirus (apv), ornithobacterium rhinotracheale (ort), mycoplasma gallisepticum, mycoplasma meleagridis and chlamydophila psittaci. at slaughter, c. psittaci, apv and ort antibodies were detected in 94, 34 and 6.5% of the turkeys, respectively. no antibodies against m. gallisepticum or m. meleagridis were present. additionally, turkeys on three belgian farms were examined f ...200515795081
mycoplasma sturni and mycoplasma gallisepticum in wild birds in scotland. 200515833969
persistence of mycoplasma gallisepticum in chickens after treatment with enrofloxacin without development of resistance.the ability of the avian pathogen mycoplasma gallisepticum to persist despite fluoroquinolone treatment was investigated in chickens. groups of specific pathogen free chickens were experimentally infected with m. gallisepticum and treated with enrofloxacin at increasing concentrations up to the therapeutic dose. when m. gallisepticum could no longer be re-isolated from chickens, birds were stressed by inoculation of infectious bronchitis virus or avian pneumovirus. although m. gallisepticum coul ...200515737482
the vlha loci of mycoplasma synoviae are confined to a restricted region of the genome.mycoplasma synoviae, a major pathogen of poultry, contains a single expressed, full-length vlha gene encoding its haemagglutinin, and a large number of vlha pseudogenes that can be recruited by multiple site-specific recombination events to generate chimaeric variants of the expressed gene. the position and distribution of the vlha pseudogene regions, and their relationship with the expressed gene, have not been investigated. to determine the relationship between these regions, a physical map of ...200515758238
differential detection of turkey coronavirus, infectious bronchitis virus, and bovine coronavirus by a multiplex polymerase chain reaction.the objective of the present study was to develop a multiplex polymerase chain reaction (pcr) method for differential detection of turkey coronavirus (tcov), infectious bronchitis coronavirus (ibv), and bovine coronavirus (bcov). primers were designed from conserved or variable regions of nucleocapsid (n) or spike (s) protein gene among tcov, ibv, and bcov and used in the same pcr reaction. reverse transcription followed by the pcr reaction was used to amplify a portion of n or s gene of the cor ...200616137773
mycoplasma genitalium mg200 and mg386 genes are involved in gliding motility but not in cytadherence.isolation and characterization of transposon-generated mycoplasma genitalium gliding-deficient mutants has implicated mg200 and mg386 genes in gliding motility. the proposed role of these genes was confirmed by restoration of the gliding phenotype in deficient mutants through gene complementation with their respective mg386 or mg200 wild-type copies. mg200 and mg386 are the first reported gliding-associated mycoplasma genes not directly involved in cytadherence. orthologues of mg200 and mg386 pr ...200616796684
ultrastructure and gliding motility of mycoplasma amphoriforme, a possible human respiratory pathogen.despite their small size and reduced genomes, many mycoplasma cells have complex structures involved in virulence. mycoplasma pneumoniae has served as a model for the study of virulence factors of a variety of mycoplasma species that cause disease in humans and animals. these cells feature an attachment organelle, which mediates cytadherence and gliding motility and is required for virulence. an essential component of the architecture of the attachment organelle is an internal detergent-insolubl ...200616804191
effects of s6-strain mycoplasma gallisepticum inoculation at ten, twenty-two, or forty-five weeks of age on the egg yolk composition of commercial egg-laying hens.commercial laying hens maintained under controlled conditions were experimentally inoculated with the s6 strain of mycoplasma gallisepticum (s6mg) at 45 wk of age. this resulted in depressed liver lipid concentration, and inoculations at 20 and 45 wk affected the size of various portions of the reproductive tract. in 2 consecutive trials of the current study, the effect of age of application of s6mg inoculation on the egg yolk characteristics of commercial layers similarly housed and maintained ...200616903485
effects of s6-strain mycoplasma gallisepticum inoculation at ten, twenty-two, or forty-five weeks of age on the blood characteristics of commercial egg-laying hens.in 2 consecutive trials of the current study, the effect of the age of application of s6-strain mycoplasma gallisepticum (s6mg) inoculation on the blood characteristics of commercial layers housed and maintained under controlled conditions was determined. the ages of inoculation compared were those before lay at 10 wk of age, during onset of lay at 22 wk of age, and during postpeak lay at 45 wk of age. in each trial, hematocrit, plasma protein, and serum cholesterol, triglycerides, and ca were d ...200617032838
identification of fibronectin-binding proteins in mycoplasma gallisepticum strain r.we have determined that virulent mycoplasma gallisepticum strain rlow is capable of binding the extracellular matrix protein fibronectin. fibronectin was found to be present in m. gallisepticum rlow protein extracts by western blotting and peptide sequencing. mycoplasma gallisepticum rhigh, the attenuated, high-passage derivative of rlow, is deficient in this ability. mga_1199, the m. gallisepticum homologue of the cytadherence-associated protein p65 from mycoplasma pneumoniae, and mga_0928, the ...200616495551
the cellular immune response in the tracheal mucosa to mycoplasma gallisepticum in vaccinated and unvaccinated chickens in the acute and chronic stages of disease.mycoplasma gallisepticum causes a lymphoproliferative response in the tracheal mucosa of infected birds. the studies reported here aimed to determine, using immunohistochemical and immunofluorescent staining, which lymphocyte subsets were infiltrating the mucosa during the acute and chronic phases of disease and to determine whether these subsets differed in birds that had been vaccinated with strain ts-11. in vaccinates there was no detectable infiltration of t or b lymphocytes between 1 and 6 ...200616406173
genotypic analyses of mycoplasma gallisepticum isolates from songbirds by random amplification of polymorphic dna and amplified-fragment length polymorphism.mycoplasma gallisepticum (mg) conjunctivitis emerged in 1994 as a disease of free-ranging house finches (carpodacus mexicanus) in north america and has also been isolated from other songbirds with conjunctivitis. random amplification of polymorphic dna (rapd) of house finch and other songbird isolates has suggested that a single 'strain' initiated this outbreak. to explore the possibility of genomic variability among house finch isolates of mg and to evaluate the utility of a second technique fo ...200616870869
further western spread of mycoplasma gallisepticum infection of house finches.mycoplasma gallisepticum, an important pathogen of poultry, especially chickens and turkeys, emerged in 1994 as the cause of conjunctivitis in house finches (carpodacus mexicanus) in their eastern range of north america. the resulting epidemic of m. gallisepticum conjunctivitis severely decreased house finch abundance and the continuing endemic disease in the eastern range has been associated with repeating seasonal peaks of conjunctivitis and limitation of host populations. mycoplasma gallisept ...200616870870
serological survey of the infectious disease status of old english game fowl in the lower north island, new zealand.to investigate the serological status of old english game (oeg) cockerels for a range of infectious diseases of poultry.200616915341
characterization of experimental mycoplasma gallisepticum infection in captive house finch flocks.the use of controlled, horizontal-transmission experiments provides detailed information on the spread of disease within fixed social groups, which informs our understanding of disease dynamics both in an empirical and theoretical context. for that reason, we characterized in 2002, horizontal transmission of mycoplasma gallisepticum (mg) in two flocks of 11 wild-caught house finches housed in outdoor aviaries over a 6-mo period. all birds were initially free of mg by a polymerase chain reaction ...200616617979
a cdna macroarray approach to parasite-induced gene expression changes in a songbird host: genetic response of house finches to experimental infection by mycoplasma gallisepticum.in 1994, the bacterial parasite mycoplasma gallisepticum expanded its host range and swept through populations of a novel host--eastern us populations of the house finch (carpodacus mexicanus). this epizootic caused a dramatic decline in finch population numbers, has been shown to have caused strong selection on house finch morphology, and presumably caused evolutionary change at the molecular level as finches evolved enhanced resistance. as a first step toward identifying finch genes that respo ...200616626453
effects of s6-strain mycoplasma gallisepticum inoculation at 10, 22, or 45 weeks of age on the digestive and reproductive organ characteristics of commercial egg-laying hens.experimental inoculation of commercial laying hens with the s6-strain of mycoplasma gallisepticum (s6mg) at 20 wk of age, while being maintained under ideal conditions, has previously been shown to affect the lengths and weights of various portions of the reproductive tract. two trials were conducted in the current study to compare the effects of s6mg inoculation prior to lay at 10 wk of age, during onset of lay at 22 wk of age, and during lay at 45 wk of age on the digestive and reproductive or ...200616673758
age related differences in the immune response to vaccination and infection with mycoplasma gallisepticum.several studies have suggested that there are age related differences in the responses of chickens to vaccination and infection with mycoplasma gallisepticum, but there have not been any systematic comparisons of the responses of young birds to vaccination with those of birds the same age to infection. the aim of the studies described here was to examine the immune responses of chickens between 1 and 6 weeks of age to vaccination and to infection with m. gallisepticum. birds under 4 weeks of age ...200616288936
identification of a virulence-associated determinant, dihydrolipoamide dehydrogenase (lpd), in mycoplasma gallisepticum through in vivo screening of transposon mutants.to effectively analyze mycoplasma gallisepticum for virulence-associated determinants, the ability to create stable genetic mutations is essential. global m. gallisepticum mutagenesis is currently limited to the use of transposons. using the gram-positive transposon tn4001mod, a mutant library of 110 transformants was constructed and all insertion sites were mapped. to identify transposon insertion points, a unique primer directed outward from the end of tn4001mod was used to sequence flanking g ...200616428737
the effect of vaccination with a bacterin on the horizontal transmission of mycoplasma gallisepticum.the effect of an inactivated vaccine on the horizontal transmission of mycoplasma gallisepticum was quantified in a transmission model. twenty non-vaccinated and 20 vaccinated 23-week-old specific pathogen free hens were housed in pairs, while five individually housed hens acted as a negative control group. each pair consisted of a challenged chicken (10(4) colony forming units intratracheally) and a non-challenged susceptible contact bird. infection was monitored by serology, quantitative polym ...200616448940
molecular characterization of mg isolates using rapd and pfge isolated from chickens in brazil.in the present study, 27 primers were screened under different cycles by random amplified polymorphic dna (rapd) method. mathematical models were used for analysis of the genetic relationships among strains, including vaccinal, reference strains and nine field isolates previously characterized as mycoplasma gallisepticum (mg)f by rapd and pulsed field gel electrophoresis (pfge). the pfge was considered as laborious, expensive and time-consuming than rapd method. these methods improved the typeab ...200617062123
spatial spread of an emerging infectious disease: conjunctivitis in house finches.in this paper we quantify the rate of spread of the newly emerged pathogen mycoplasma gallisepticum of the house finch, carpodacus mexicanus, in its introduced range. we compare and contrast the rapid, yet decelerating, rate of spread of the pathogen with the slower, yet accelerating rate of spread of the introduced host. comparing the rate of spread of this pathogen to pathogens in terrestrial mammalian hosts, we see that elevation and factors relating to host abundance restrict disease spread, ...200617249229
separating mycoplasma gallisepticum field strains from nonpathogenic avian mycoplasmas.mycoplasma gallisepticum (mg) has repeatedly emerged as a serious problem in u.s. broiler, layer, and turkey industries. tracing the source of an outbreak is essential if mg control is to be accomplished. amplified fragment length polymorphism (aflp), random amplification of polymorphic dna (rapd), and restriction fragment length polymorphism (rflp) are valuable tools used to study mg epidemiology, allowing diagnosticians to determine the source of mg infections. in some past outbreaks, aflp, ra ...200617274301
differentiation of mycoplasma gallisepticum strains using molecular methods.increasing use of mycoplasma gallisepticum (mg) live vaccines has led to a need for the differentiation of mg strains. the mg strains mk-7, ms-16, s6, fs-9 and r strains and the mg live vaccine strain f were compared by random amplification of polymorphic dna (rapd) in this study. using rapd, different patterns were found among the mg strains. in addition to this, we examined the differentiating potential of polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) primers ta ...200617278716
the effect of a live vaccine on the horizontal transmission of mycoplasma gallisepticum.the effect of a live mycoplasma gallisepticum vaccine on the horizontal transmission of this mycoplasma species was quantified in an experimental animal transmission model in specific pathogen free white layers. two identical trials were performed, each consisting of two experimental groups and one control group. the experimental groups each consisted of 20 birds 21 weeks of age, which were housed following a pair-wise design. one group was vaccinated twice with a commercially available live att ...200616990145
development and validation of a real-time taqman polymerase chain reaction assay for the detection of mycoplasma gallisepticum in naturally infected birds.in this study, we report the development and validation of a real-time polymerase chain reaction (pcr) assay using a taqman-labeled probe for the detection of mycoplasma gallisepticum (mglp assay). the mglp assay was highly specific with a detection limit of 25 template copies per reaction and a quantification limit of 100 template copies per reaction. validation of the assay was completed with 1247 samples (palatine cleft and tracheal swabs) from m. gallisepticum-positive and -negative chicken ...200617274291
experimental infection of chickens and turkeys with mycoplasma gallisepticum reference strain s6 and north carolina field isolate rapd type b.during an epidemic of mycoplasmosis in chicken and turkey flocks in north carolina between 1999 and 2001, isolates of mycoplasma gallisepticum (mg) from affected flocks were characterized by random amplification of polymorphic dna (rapd), and eight distinct rapd types were identified. mg rapd type b accounted for more than 90% of the isolates and was associated with moderate-to-severe clinical signs and mortality. the virulence of mg rapd type b for chickens and turkeys was compared with sham-in ...200717461274
experimental evidence for transmission of mycoplasma gallisepticum in house finches by fomites.ever since mycoplasma gallisepticum emerged among house finches in north america, it has been suggested that bird aggregations at feeders are an important cause of the epidemic of mycoplasmal conjunctivitis because diseased birds could deposit droplets of pathogen onto the feeders and thereby promote indirect transmission by fomites. in this paper we bring the first experimental evidence that such transmission (bird-to-feeder-to-bird) does actually take place. house finches infected via this rou ...200717497332
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
evolutionary genetics of carpodacus mexicanus, a recently colonized host of a bacterial pathogen, mycoplasma gallisepticum.we present molecular data documenting how introduction to the eastern united states and an epizootic involving a bacterial pathogen has affected the genetic diversity of house finches, a cardueline songbird. population bottlenecks during introduction can cause loss of genetic variation and may negatively affect a population's ability to adapt to novel stressors such as disease. although a genome-wide survey using amplified fragment length polymorphism (aflp) markers suggests little loss of genet ...200717103248
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
interlaboratory comparison of ability to detect nucleic acid of mycoplasma gallisepticum and mycoplasma synoviae by polymerase chain reaction.in recent years polymerase chain reaction (pcr) assays have become widely used as methods to confirm the presence of mycoplasma gallisepticum and mycoplasma synoviae in poultry flocks, but there has been limited standardization of the protocols used. thirteen laboratories from five different countries participated in an interlaboratory comparison of detection of m. gallisepticum and m. synoviae dna by pcr in samples that contained 10-fold dilutions of these bacteria. the concentration of bacteri ...200717479373
state-specific detection probabilities and disease prevalence.investigations of disease dynamics in wild animal populations often use estimated prevalence or incidence as a measure of true disease frequency. such indices, almost always based solely on raw counts of infected and uninfected individuals, are often used as the basis for analysis of temporal and spatial dynamics of diseases. generally, such studies do not account for potential differences in observer detection probabilities of host individuals stratified by biotic and/or abiotic factors. we dem ...200717479842
effects of supplemental dietary phytase and 25-hydroxycholecalciferol on the blood characteristics of commercial layers inoculated before or at the onset of lay with the f-strain of mycoplasma gallisepticum.in 3 trials, the effects of dietary supplementation with phytase (phy) and 25-hydroxycholecalciferol on bw and the blood characteristics of commercial layers that were inoculated prelay (12 wk of age) or at the onset of lay (22 wk of age) with f-strain mycoplasma gallisepticum were assessed at 34, 50, and 58 wk of age. experimental layer diets, which included either a basal control diet or the same diet supplemented with 0.025% phy and 25-hydroxycholecalciferol, were fed from 20 through 58 wk of ...200717369552
the mycoplasma gallisepticum 16s-23s rrna intergenic spacer region sequence as a novel tool for epizootiological studies.mycoplasma gallisepticum (mg) contains two sets of rrna genes (5s, 16s and 23s) in its genome, but only one of the two is organized in an operon cluster and contains a unique 660-nucleotide intergenic spacer region (igsr) between the 16s and the 23s rrna genes. we designed a polymerase chain reaction (pcr) for the specific amplification of the complete mg igsr segment. the mg igsr pcr was tested on 18 avian mollicute species and was confirmed as mg specific. the reaction sensitivity was demonstr ...200717626483
effects of supplemental dietary phytase and 25-hydroxycholecalciferol on the digestive and reproductive organ characteristics of commercial layers inoculated before or at the onset of lay with the f-strain of mycoplasma gallisepticum.in 3 trials, the effects of dietary supplementation with phytase (phy) and 25-hydroxycholecalciferol (25-d3) on the digestive and reproductive organ characteristics of commercial layers that were inoculated prelay (12 wk of age) or at the onset of lay (22 wk of age) with f-strain mycoplasma gallisepticum (fmg) were assessed at 58 wk of age. experimental layer diets that included a basal control diet or a control diet supplemented with 0.025% phy and 25-d3 were fed from 20 through 58 wk of age. a ...200717626828
transcriptional responses of mycoplasma gallisepticum strain r in association with eukaryotic cells.mycoplasma gallisepticum is an etiologic agent of chronic respiratory disease in chickens and infectious sinusitis in turkeys. other than proteins important for cytadherence, few m. gallisepticum factors or pathways contributing to host cell interactions have been identified. in this study, an oligonucleotide-based microarray was utilized to investigate transcriptional changes in m. gallisepticum strain r(low) upon exposure to eukaryotic cells. fifty-eight genes were either up- or downregulated ...200717557819
recombinant plasmid constructs expressing gene for antimicrobial peptide melittin for the therapy of mycoplasma and chlamydia infections.in view of growing number of pathogenic microbial strain resistant to routine antibiotics, antimicrobial peptides become promising agents for the therapy of infectious diseases. we studied in vivo effects of melittin, an antimicrobial peptide expressed in a recombinant plasmid vector, on infection with urogenital pathogens chlamydia trachomatis, mycoplasma hominis, and mycoplasma gallisepticum. we obtained recombinant plasmid constructs, where melittin gene is under the control of tetracycline-d ...200718457054
mycoplasma gallisepticum 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
contrasting natural experiments confirm competition between house finches and house sparrows.after house finches were introduced from the western to the eastern united states and rapidly increased in numbers, house sparrows declined, leading to suggestions that the decline was caused by interspecific competition. however, other potential causes were not excluded. the rapid decline in house finches following the emergence of a new disease (mycoplasmal conjunctivitis) caused by a novel strain of mycoplasma gallisepticum (mg) in 1994 has provided a natural experiment and an opportunity to ...200717536703
molecular characterization and determination of antimicrobial resistance of mycoplasma gallisepticum isolated from chickens.in this study, three consecutive approaches of molecular characterization, determination of minimum inhibitory concentration (mic) and antimicrobial tested on mycoplasma gallisepticum (mg) isolated from chicken farms were investigated. these approaches were conducted between 2004 and 2005 to 134 mg samples collected from five different regions of the intensive farming area of thailand. twenty mg isolates and four reference strains including s6, f, ts-11, and 6/85 were classified according to ran ...200717570621
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
the mycoplasma gallisepticum osmc-like protein mg1142 resides on the cell surface and binds heparin.mycoplasma gallisepticum is an avian pathogen that causes a chronic respiratory disease of chickens and results in significant economic losses to the poultry industry worldwide. colonization of the host and the establishment of chronic disease are initiated by the cytadherence of m. gallisepticum to the host respiratory epithelium. while several proteins involved in cytadhesion have been characterized, molecules that interact with components of the host extracellular matrix, a process that is ce ...200717464059
survey of campylobacter, salmonella and mycoplasmas in house crows (corvus splendens) in malaysia.house crows (corvus splendens) in selangor, malaysia were examined for the presence of campylobacter species, salmonella species, mycoplasma gallisepticum and mycoplasma synoviae by serology, culture and pcr. for the detection of campylobacter and salmonella species swabs were taken either from the intestine or cloaca. for the detection of mycoplasmas, swabs were taken either from the choanal cleft or trachea for culture and pcr and serum samples were tested by the rapid serum agglutination (rsa ...200717483380
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
synthetic biology. attempt to patent artificial organism draws a protest. 200717569837
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
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
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
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 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
[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
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
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
comparative assessment of a metabolically attenuated mycoplasma gallisepticum mutant as a live vaccine for the prevention of avian respiratory mycoplasmosis.in a previous study, signature sequence mutagenesis (ssm) was used to identify a mutant with a disruption of the gene encoding the metabolic factor, dihydrolipoamide dehydrogenase, and that mutant was designated mg 7. the current study assessed the safety, immunogenicity and efficacy of mg 7 in comparison to two commercially available vaccines (ts-11 and f) as well as a laboratory vaccine strain, gt5. intratracheal vaccination of chickens with all four attenuated mutants induced varying levels o ...200818342996
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
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
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
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
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 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
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
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
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
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
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
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
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
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
in vitro susceptibilities to fluoroquinolones in current and archived mycoplasma gallisepticum and mycoplasma synoviae isolates from meat-type turkeys.monitoring of susceptibility to antibiotics in field isolates of pathogenic avian mycoplasmas is important for appropriate choice of treatment. our study compared in vitro susceptibility to enrofloxacin and difloxacin in recent (2005-2006) isolates of mycoplasma gallisepticum and mycoplasma synoviae from meat-type turkey flocks with archived (1997-2003) isolates and reference strains. comparison of minimal inhibitory concentration (mic) values determined by microtest, agar dilution and commercia ...200818534788
effects of 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
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
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
mycoplasma gallisepticum invades chicken erythrocytes during infection.recently, it was demonstrated using in vitro assays that the avian pathogen mycoplasma gallisepticum is able to invade nonphagocytic cells. it was also shown that this mycoplasma can survive and multiply intracellularly for at least 48 h and that this cell invasion capacity contributes to the systemic spread of m. gallisepticum from the respiratory tract to the inner organs. using the gentamicin invasion assay and a differential immunofluorescence technique combined with confocal laser scanning ...200817954728
mycoplasma gallisepticum 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
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
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
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
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
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