Publications

TitleAbstractYear
Filter
PMID(sorted descending)
Filter
re-exposure of captive house finches that recovered from mycoplasma gallisepticum infection.fourteen house finches were reinoculated (re-exposed) with 0.05 ml (3.24x10(5) colony forming units/ml) of mycoplasma gallisepticum (mg) in the conjunctival sac of each eye. all birds used in this reinoculation study had recovered from previous infection between 27 and 83 days after inoculation. recovery was based on the absence of clinical signs of conjunctivitis and/ or the inability to detect mg in conjunctival or choanal samples. birds were maintained in individual cages under controlled env ...200516107667
susceptibility of wild songbirds to the house finch strain of mycoplasma gallisepticum.conjunctivitis in house finches (carpodacus mexicanus), caused by mycoplasma gallisepticum (mg), was first reported in 1994 and, since this time, has become endemic in house finch populations throughout eastern north america. although the house finch is most commonly associated with mg-related conjunctivitis, mg has been reported from other wild bird species, and conjunctivitis (not confirmed as mg related) has been reported in over 30 species. to help define the host range of the house finch st ...200516107666
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
use of mgc2-polymerase chain reaction-restriction fragment length polymorphism for rapid differentiation between field isolates and vaccine strains of mycoplasma gallisepticum in israel.increasing use of mycoplasma gallisepticum (mg) live vaccines has led to a need for a rapid test for differentiation of mg field strains from the live vaccine strains ts-11 and 6/85. we examined the differentiating potential of diagnostic polymerase chain reaction (pcr) primers targeted to the gene mgc2, encoding a cytadherence-related surface protein uniquely present in mg. the mgc2-pcr diagnostic primers are specific for mg in tests of all avian mycoplasmas or bacteria present in the chicken t ...200516094829
swine and poultry pathogens: the complete genome sequences of two strains of mycoplasma hyopneumoniae and a strain of mycoplasma synoviae.this work reports the results of analyses of three complete mycoplasma genomes, a pathogenic (7448) and a nonpathogenic (j) strain of the swine pathogen mycoplasma hyopneumoniae and a strain of the avian pathogen mycoplasma synoviae; the genome sizes of the three strains were 920,079 bp, 897,405 bp, and 799,476 bp, respectively. these genomes were compared with other sequenced mycoplasma genomes reported in the literature to examine several aspects of mycoplasma evolution. strain-specific region ...200516077101
gordon memorial lecture. poultry mycoplasmas: sophisticated pathogens in simple guise.mycoplasmas are a genus within the class mollicutes (trivial name mollicutes), which are the smallest known prokaryotes capable of self-replication. they have a very small genome, and have evolved to this 'minimalist' status by losing non-essential genes, including those involved in cell wall synthesis. the mollicutes exploit their limited genetic material to the maximum and many are successful pathogens in man, animals, birds and plants. most of those of veterinary importance are in the genus m ...200515957431
use of molecular diversity of mycoplasma gallisepticum by gene-targeted sequencing (gts) and random amplified polymorphic dna (rapd) analysis for epidemiological studies.a total of 67 mycoplasma gallisepticum field isolates from the usa, israel and australia, and 10 reference strains, were characterized by gene-targeted sequencing (gts) analysis of portions of the putative cytadhesin pvpa gene, the cytadhesin gapa gene, the cytadhesin mgc2 gene, and an uncharacterized hypothetical surface lipoprotein-encoding gene designated genome coding dna sequence (cds) mga_0319. the regions of the surface-protein-encoding genes targeted in this analysis were found to be sta ...200515941996
induction of macrolide resistance in mycoplasma gallisepticum in vitro and its resistance-related mutations within domain v of 23s rrna.antibiotic-resistant mutants of mycoplasma gallisepticum were selected in vitro from the susceptible strains s6 and bg44t by serial passages in stepwise concentrations of erythromycin, tylosin, or tilmicosin. high resistance to erythromycin or tilmicosin developed readily, whereas resistance to tylosin developed only after greater numbers of passages. three mutants selected by each selector antibiotic were cloned and detected, and all cloned mutants exhibited cross-resistance to the three select ...200515936901
stress responses and disease in three wintering house finch (carpodacus mexicanus) populations along a latitudinal gradient.in laboratory studies, stress hormones have been shown to impair immune functions, and increase susceptibility to diseases. however, the interactions between stress hormones and disease have rarely been studied in free-ranging populations. in this study, we measured concentrations of the avian stress hormone corticosterone across four winter months (december-march) over two years in three eastern north american house finch populations (carpodacus mexicanus) along a latitudinal gradient. because ...200515922346
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
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
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
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
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
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
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
mycoplasma sturni and mycoplasma gallisepticum in wild birds in scotland. 200515833969
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
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
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
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
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
effects of mycoplasma gallisepticum on reproductive success in house finches.long known as a pathogen of poultry, mycoplasma gallisepticum (mg) was first detected in house finches in 1994. the disease rapidly spread throughout the eastern united states and canada and was associated with debilitating disease and high mortality in house finches. however, in the late 1990s, the proportion of infected finches dying as a result of infection with mg decreased, and asymptomatic infection was more common among wild birds than in the past. we documented mg infections in breeding ...200415666869
inactivation, storage, and pcr detection of mycoplasma on fta filter paper.we evaluated the feasibility of using flinders technology associates (fta) filter paper for the inactivation and storage of mycoplasma dna templates and their detection by the polymerase chain reaction (pcr). fta paper is a cotton-based cellulose membrane containing lyophilized chemicals that lyses most types of bacteria and viruses. mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) cultures were spotted at various volumes on the filter paper and stored at different temperatures for var ...200415666865
seasonality and wildlife disease: how seasonal birth, aggregation and variation in immunity affect the dynamics of mycoplasma gallisepticum in house finches.we examine the role of host seasonal breeding, host seasonal social aggregation and partial immunity in affecting wildlife disease dynamics, focusing on the dynamics of house finch conjunctivitis (mycoplasma gallisepticum (mg) in carpodacus mexicanus). this case study of an unmanaged emerging infectious disease provides useful insight into the important role of seasonal factors in driving ongoing disease dynamics. seasonal breeding can force recurrent epidemics through the input of fresh suscept ...200415615682
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
testing the efficacy of fermented wheat germ extract against mycoplasma gallisepticum infection of chickens.the effect of fermented wheat germ extract (fwge, immunovet-hbm) was studied in chickens challenged with mycoplasma gallisepticum. ninety m. gallisepticum- and m. synoviae-free 3-wk-old chickens were exposed to aerosol infection of m. gallisepticum. one group (30 birds) was treated with fwge, a second group with tiamulin, and a third group was untreated. the fourth group was exposed to pbs aerosol as a negative control. on d 9, all chickens were slaughtered and examined for the presence of gross ...200415554060
safety of mycoplasma gallisepticum vaccine strain 6/85 after backpassage in turkeys.the objective of this research was to evaluate the safety of the 6/85 strain vaccine strain of mycoplasma gallisepticum in turkeys by backpassing the vaccine strain up to 10 times by contact infection in turkeys and challenging turkeys with the resulting backpassaged strain. the vaccine strain, however, did not spread to in-contact turkeys, and it was necessary to reisolate the organism before challenging turkeys for the next passage. the challenge strain, therefore, was one that had been backpa ...200415529988
molecular characterization of mycoplasma gallisepticum isolates from turkeys.mycoplasma gallisepticum was isolated from several turkey flocks at different locations in the united states that were clinically affected with respiratory disease. five of these isolates from four series of outbreaks had patterns similar to the 6/85 vaccine strain of m. gallisepticum by random amplified polymorphic dna (rapd) analysis using three different primer sets, whereas with a fourth primer set (opa13 and opa14), only two of the isolates were similar to 6/85. results obtained by sequenci ...200415529978
morphologic changes in chicken cells after in vitro exposure to mycoplasma gallisepticum.mycoplasma gallisepticum (mg) was used to expose chicken peripheral blood lymphocytes (pbls), red blood cells (rbcs), heterophils, and chicken tumor cells (msb-1 and hd-11 cells). incubation of pbls with mg for 3 hr resulted in extensive clumping of lymphocytes. incubation of the msb-1 cells with mg also caused clumping of the cells, with many of the cells showing perforations and others showing capping of the surface projections. incubation of rbcs with mg resulted in an altered cell surface mo ...200415529970
disposition kinetics of doxycycline in chickens naturally infected with mycoplasma gallisepticum.1. the pharmacokinetic properties of doxycycline were determined in healthy chickens and chickens naturally infected with mycoplasma gallisepticum after a single intravenous (i.v.) and oral administration of the drug at 20 mg/kg body weight. tissue residues of the tested drug after an oral dose of 20 mg/kg given twice daily for 5 consecutive days were also estimated in diseased chickens. 2. the plasma concentrations of doxycycline following single i.v. and oral administration were higher in heal ...200415484732
aerosolization of mycoplasma synoviae compared with mycoplasma gallisepticum and enterococcus faecalis.in order to study the airborne transmission of an arthropathic strain of mycoplasma synoviae, preliminary aerosol experiments were performed. they were conducted in duplicate in an empty isolator (1.3 m3) to assess the yield and viability of m. synoviae with time compared with mycoplasma gallisepticum and enterococcus faecalis. after aerosol generation air samples were taken with two different devices using gelatine or cellulose nitrate filters. there was no difference between the devices, but c ...200415276990
significance of interactions between escherichia coli and respiratory pathogens in layer hen flocks suffering from colibacillosis-associated mortality.this study aimed to examine the significance of interactions between escherichia coli and various respiratory pathogens during outbreaks of colibacillosis-associated mortality in layer hen flocks under field conditions. for this purpose, a case-control study involving 20 control flocks with baseline mortality and 20 flocks with increased mortality due to e. coli septicaemia and polyserositis, was conducted. in each colibacillosis flock, blood samples were taken from 20 hens at the onset of clini ...200415223556
a serological survey for pathogens in old fancy chicken breeds in central and eastern part of the netherlands.to get an impression of the presence of pathogens in multi-aged flocks of old fancy chicken breeds in the netherlands, plasma samples originating from 24 flocks were examined for antibodies against 17 chicken pathogens. these flocks were housed mainly in the centre and east of the netherlands, regions with a high poultry density. the owners of the tested flocks showed their chicken at national and international poultry exhibitions. antibodies against avian influenza, egg drop syndrome '76 virus, ...200415185615
induced expression of the antimicrobial peptide melittin inhibits experimental infection by mycoplasma gallisepticum in chickens.the in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with mycoplasma gallisepticum was studied. the plasmid vector pbi/mel2/rtta includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtta. aerosol administration of the vector, followed by infecting the chickens with m. gallisepticum 1226, is shown t ...200415158186
the effect of mycoplasmosis on carotenoid plumage coloration in male house finches.parasites are widely assumed to cause reduced expression of ornamental plumage coloration, but few experimental studies have tested this hypothesis. we captured young male house finches carpodacus mexicanus in alabama before fall molt and randomly divided them into two groups. one group was infected with the bacterial pathogen mycoplasma gallicepticum (mg) and the other group was maintained free of mg infection. all birds were maintained through molt on a diet of seeds with tangerine juice added ...200415143143
experimental infection of house finches with mycoplasma gallisepticum.mycoplasma gallisepticum (mg) has caused an endemic upper respiratory and ocular infection in the eastern house finch (carpodacus mexicanus) after the epidemic first described in 1994. the disease has been studied by a number of investigators at a population level and reports describe experimental infection in group-housed mg-free house finches. because detailed observation and evaluation of individual birds in group-housed passerines is problematic, we studied individually housed house finches ...200415137491
geneorder3.0: software for comparing the order of genes in pairs of small bacterial genomes.an increasing number of whole viral and bacterial genomes are being sequenced and deposited in public databases. in parallel to the mounting interest in whole genomes, the number of whole genome analyses software tools is also increasing. geneorder was originally developed to provide an analysis of genes between two genomes, allowing visualization of gene order and synteny comparisons of any small genomes. it was originally developed for comparing virus, mitochondrion and chloroplast genomes. th ...200415128433
mycoplasma gallisepticum--induced alterations in cytokine genes in chicken cells and embryos.mycoplasma gallisepticum (mg) was used to infect the msb-1 cells, the hd-11 cells, and chicken embryos. the rna from these cells and the embryonic spleen cells were extracted and assayed for the expression of cytokine genes using reverse transcription-polymerase chain reaction. the results showed that mg infection suppressed the expression of the il-8 gene in the msb-1 cells and enhanced the expression of the il-8 and il-6 genes in the hd-11 cells; a slightly increased expression of macrophage i ...200415077819
effects of an s6 strain of mycoplasma gallisepticum inoculation before beginning of lay on the leukocytic characteristics of commercial layers.a clinical study was conducted on commercial layers housed in biological isolation units, within which exogenous stress factors potentially affecting bird performance were minimized. this set-up was devised in order to assess how a pre-lay inoculation of s6 strain mycoplasma gallisepticum affects the leukocytic properties of laying chickens. previous studies have demonstrated relative decreases in lymphocyte and relative increases in heterophil percentages in birds infected with other strains of ...200415077815
safety and efficacy of the avirulent mycoplasma gallisepticum strain k5054 as a live vaccine in poultry.a mycoplasma gallisepticum (mg) isolate from an atypically mild outbreak in turkey breeders was found to be similar to house finch isolates by dna analyses. a preliminary study in turkeys showed that this isolate (k5054) caused very mild lesions and protected turkeys against subsequent challenge with a virulent mg strain. in this study, k5054 was further evaluated as a potential vaccine strain in commercial layer-type chickens and turkeys. the safety of k5054 was evaluated by aerosol challenge f ...200415077802
health survey of house finches (carpodacus mexicanus) from wisconsin.we conducted a health survey of house finches (carpodacus mexicanus) without evidence of mycoplasma gallisepticum infection in order to establish baseline population health measures and estimate prevalence of potential pathogens likely to influence host susceptibility to mycoplasmosis. seasonal changes in several physiologic parameters were observed. weights were greater in winter compared with the breeding season (p < 0.01), fat scores were greater in winter than during fall migration (p < 0.01 ...200415077801
survey of peafowl (pavo cristatus) for potential pathogens at three michigan zoos.blood samples collected from 31 free-roaming peafowl from three zoos in michigan were tested serologically. antibody titers were present against avian adenovirus and bordetella avium in 19.3% and 61.3% of the samples, respectively. serum plate agglutination tests were positive for mycoplasma meleagridis and mycoplasma synoviae in 3.2% and 38.7% of the samples, respectively. all birds were seronegative for avian influenza, newcastle disease virus, west nile virus, mycoplasma gallisepticum, salmon ...200315077714
a putative transposase gene in the 16s-23s rrna intergenic spacer region of mycoplasma imitans.examination of the nucleotide sequences of the 16s-23s intergenic transcribed spacer (its) region of mycoplasma imitans and mycoplasma gallisepticum identified a putative transposase gene located only in the its of m. imitans, which can be used as a genetic marker to distinguish these two species. the relative size of the pcr products of the its region allowed a clear distinction to be made between strains of m. imitans and m. gallisepticum, both of which could be readily discriminated from the ...200415073311
shrinking genomics.two bacteria are featured this month, and both are at the lower end of the genome size scale. the first, mycoplasma gallisepticum, belongs to a group of bacteria that have been studied both as important human and animal pathogens and in the pursuit of understanding the essential functions of a self-replicating minimal cell. the second, nanoarchaeum equitans, is an obligate symbiont that only grows in co-culture with another archaeon. n. equitans seems to be the coelacanth of the microbial world- ...200415035003
effects of mushroom and herb polysaccharides, as alternatives for an antibiotic, on the cecal microbial ecosystem in broiler chickens.an in vivo experiment was conducted to study the potential prebiotic effects of mushroom and herb polysaccharide extracts, lentinus edodes extract (lene), tremella fuciformis extract, and astragalus membranaceus radix extract, on chicken growth and the cecal microbial ecosystem, as compared with the antibiotic apramycin (apr). this investigation was carried out in terms of a dose-response study. the chickens were naturally infected with avian mycoplasma gallisepticum prior to the experiment. the ...200414979567
molligen, a database dedicated to the comparative genomics of mollicutes.bacteria belonging to the class mollicutes were among the first ones to be selected for complete genome sequencing because of the minimal size of their genomes and their pathogenicity for humans and a broad range of animals and plants. at this time six genome sequences have been publicly released (mycoplasma genitalium, mycoplasma pneumoniae, ureaplasma urealyticum-parvum, mycoplasma pulmonis, mycoplasma penetrans and mycoplasma gallisepticum) and as the number of available mollicute genomes inc ...200414681420
effects of f-strain mycoplasma gallisepticum inoculation on serum very low density lipoprotein diameter and fractionation of cholesterol among lipoproteins in commercial egg-laying hens.experimental inoculation with the f-strain of mycoplasma gallisepticum (fmg) at 12 wk of age has been shown to affect the performance, liver, reproductive organs, and yolk lipid characteristics of commercial layers. therefore, this study was conducted to determine the serum lipoprotein characteristics of commercial egg-laying hens at 16 wk of age and throughout lay after inoculation with fmg at 12 wk of age. mean diameters of very low density lipoproteins (vldl) were determined for the 10th, 50t ...200314601743
avian influenza (h9n2) outbreak in iran.an epidemic of avian influenza (ai) (h9n2) occurred in broiler chicken farms in iran during 1998-01. mortality between 20% and 60% was commonly observed on the affected farms. mixed infections of the influenza virus with other respiratory pathogens, particularly infectious bronchitis virus and mycoplasma gallisepticum, were thought to be responsible for such high mortality, which resulted in great economic losses. clinical signs included swelling of the periorbital tissues and sinuses, typical r ...200314575072
induction of a mycoplasma gallisepticum pmga gene in the chicken tracheal ring organ culture model.genetic and molecular methods to investigate the pathogenesis of the poultry respiratory pathogen mycoplasma gallisepticum are quite limited. therefore, the objective of this study was to design and evaluate a functional genomics approach to identify m. gallisepticum genes involved in colonization of the poultry respiratory tract. to serve as a transcriptional reporter, a promoterless lacz gene from escherichia coli was cloned into the tn4001 transposon. the transposon was used to randomly mutag ...200314562906
real-time polymerase chain reaction for mycoplasma gallisepticum in chicken trachea.in this work, we describe a rapid detection procedure for mycoplasma gallisepticum from chicken tracheal swabs by real-time polymerase chain reaction (pcr) by lightcycler system, where we were able to monitor the amplification of the newly synthesized m. gallisepticum-specific pcr product as a proportionally increasing fluorescent signal by using the double-stranded dna binding dye sybr green i and have identified m. gallisepticum-specific pcr products by dna melting curve analysis by plotting t ...200314562901
molecular variability of house finch mycoplasma gallisepticum isolates as revealed by sequencing and restriction fragment length polymorphism analysis of the pvpa gene.mycoplasma gallisepticum, a major pathogen of chickens and turkeys, has caused significant declines in house finch (carpodacus mexicanus) populations in the eastern united states since it was first observed in this species in 1994. there is evidence that m. gallisepticum infection is now endemic among eastern house finches, although disease prevalence has declined, suggesting an evolving host-parasite relationship. studies based on randomly amplified polymorphic dna (rapd) have documented the pr ...200314562892
characterization of a naturally occurring infection of a mycoplasma gallisepticum house finch-like strain in turkey breeders.an outbreak of mycoplasma gallisepticum (mg) in commercial turkeys involving very mild clinical signs was difficult to confirm by routine methods. in the first part of this study (trial a), we conducted a bioassay to increase the likelihood of detecting mg. susceptible turkeys were inoculated with sinus exudates from four different affected commercial turkey flocks. turkeys were evaluated for clinical signs, as well as by serology and culture of tracheal swabs, at 21 and 42 days postchallenge. a ...200314562878
effects of cyclosporin a on the immune responses and pathogenesis of a virulent strain of mycoplasma gallisepticum in chickens.immune responses to the virulent s6 strain of mycoplasma gallisepticum in immunocompetent and cyclosporin a (csa)-treated specific pathogen free chickens were investigated, and pathogenesis of the m. gallisepticum strain was also examined. ten-day-old specific pathogen free chickens were inoculated by eye-drop with m. gallisepticum, and a control uninfected group was inoculated with mycoplasma broth. blood was collected weekly for 4 weeks from five birds in each group and whole blood lymphocyte ...200314522705
prevalence of infectious diseases in ring-necked pheasant flocks in poland.the health status of ring-necked pheasants in view of the prevalence of infectious diseases was estimated in polish pheasantries in the years 1997-2000. anatomicopathological, microbiological and serological examinations were carried out on birds derived from 26 pheasantries, including birds randomly selected from 18 flocks and sick or dead birds sent from 8 pheasantries. antibodies specific to the following viruses were detected in serum blood samples: he, ae, ap, reo, ai, adeno group 1, md, nd ...200314510048
the chemical composition and submicroscopic morphology of mycoplasma gallisepticum, avian pplo 5969. 196214476188
the effect of social stress on resistance to infection with escherichia coli or mycoplasma gallisepticum. 196514344031
comparison of tube agglutination, hemagglutination-inhibition (hi) and antiglobulin titers on serums of chickens and turkeys infected with mycoplasma gallisepticum. 196514340910
the effects of sodium sulfate in diets containing chlortetracycline hydrochloride on chicks infected with mycoplasma gallisepticum. 196514340720
response of the turkey to mycoplasma gallisepticum infection. 196514336873
serologic, pathologic, and symptomatic aspects of mycoplasmosis of turkeys.adult male turkeys were exposed to mycoplasma gallisepticum isolate 1010 by either intratracheal inoculation, intrasinus inoculation, intranasal inoculation or by contact with inoculated turkeys. the symptomatic, serologic, and pathologic responses to the different types of exposure were compared. tracheitis occurred only in birds exposed intratracheally or by contact, and sinusitis occurred only in birds exposed via the sinuses. antibody titers, determined by hemagglutination-inhibition and tub ...196514300856
chicken red blood cell adsorption test for detection of colonies of mycoplasma gallisepticum developed on agar media. 196514284965
antigenic relationship between mycoplasma synoviae and mycoplasma gallisepticum. 196514266930
brain and muscle lesions caused by mycoplasma gallisepticum in turkey poults. 196514266927
control of experimental mycoplasma gallisepticum infection in young chickens with tylosin and other antibiotics. 196514253997
gross morphology and ultrastructure of mycoplasma gallisepticum.domermuth, c. h. (statens seruminstitut, copenhagen, denmark), m. nielsen, e. a. freundt, and a. birch-andersen. gross morphology and ultrastructure of mycoplasma gallisepticum. j. bacteriol. 88:1428-1432. 1964.-the ultrastructure and gross morphology of mycoplasma gallisepticum strains ja and w were studied with an electron microscope. intact specimens were grown on parlodion membranes, fixed with formaldehyde, and studied in situ. sectioned specimens were grown on agar and were prepared for st ...196414234802
studies on the nutrition and growth requirements of mycoplasma gallisepticum. 196414171257
comparison of in vitro and in vivo activity of spiramycin and erythromycin against mycoplasma gallisepticum. 196414155349
a comparison of some characteristics of mycoplasma var. mycoides and mycoplasma gallisepticum. 196414103232
inhibition of the pleuropneumonia-like organism mycoplasma gallisepticum by certain polyene antifungal antibiotics.lampen, j. oliver (rutgers, the state university, new brunswick, n.j.), james w. gill, peter m. arnow, and i. magana-plaza. inhibition of the pleuropneumonia-like organism mycoplasma gallisepticum by certain polyene antifungal antibiotics. j. bacteriol. 86:945-949. 1963.-the growth of mycoplasma gallisepticum, a sterol-requiring pleuropneumonia-like organism (pplo), was inhibited by certain polyene antifungal antibiotics at the following concentrations: filipin, 0.5 mug/ml; amphotericin b, 3 mug ...196314080805
respiratory pathways in the mycoplasma. i. lactate oxidation by mycoplasma gallisepticum.smith, s. l. (cornell university, ithaca, n.y.), p. j. van demark, and j. fabricant. respiratory pathways in the mycoplasma. i. lactate oxidation by mycoplasma gallisepticum. j. bacteriol. 86:893-897. 1963.-resting cells of mycoplasma gallisepticum 293 required the addition of nicotinamide adenine dinucleotide, thiamine pyrophosphate, and flavine mononucleotide for the maximal rate of sodium lactate oxidation. inhibitor studies, as well as spectrophotometric and chemical assays, indicate that th ...196314080798
lipid composition and synthesis in the pleuropneumonia-like organism mycoplasma gallisepticum.tourtellotte, mark e. (university of connecticut, storrs), robert g. jensen, george w. gander, and harold j. morowitz. lipid composition and synthesis in the pleuropneumonia-like organism mycoplasma gallisepticum. j. bacteriol. 86:370-379. 1963.-a simple method of extracting lipids from cells of mycoplasma gallisepticum by use of silicic acid columns is described. proteolipids (peptides) extracted with chloroform-methanol (2:1) by other methods were not extracted with the lipid by this method, n ...196314071787
irregular variation in cellular nitrogen associated with culture age of mycoplasma gallisepticum. 196314066489
colonial growth of mycoplasma gallisepticum observed with the electron microscope.shifrine, moshe (university of california, davis), jack pangborn, and henry e. adler. colonial growth of mycoplasma gallisepticum observed with the electron microscope. j. bacteriol. 83:187-192. 1962.-mycoplasma gallisepticum strain s(6) was grown on collodion film on solid medium. samples were removed every few hours, fixed, washed, shadowed, and observed with the electron microscope. three distinct forms of growth were observed: elementary cells (hexagonally shaped), platycytes, and exoblasts. ...196213911868
culture and metabolism of mycoplasma gallisepticum.gill, james w. (university of new hampshire, durham). culture and metabolism of mycoplasma gallisepticum. j. bacteriol. 83:213-218. 1962.-mycoplasma gallisepticum a5969, a strong-growing pleuropneumonia-like organism pathogenic for poultry, was found to be intolerant of extremes of temperature and potassium ion concentration. it ferments glucose to the benefit of cell yield, but glycolysis appears not to be essential to growth. anaerobic growth can be maintained if pyruvate is added as a hydroge ...196213898603
an immunological phenomenon in chickens following infection with mycoplasma gallisepticum. 196113774131
the in vivo response of mycoplasma gallisepticum to deoxycorticosterone trimethylacetate. 196113731963
randomly amplified polymorphic dna (rapd) analysis of mycoplasma gallisepticum isolates from turkeys from the central valley of california.randomly amplified polymorphic dna (rapd) analysis was used to investigate the molecular epidemiology of 26 mycoplasma gallisepticum (mg) isolates obtained from turkeys located in the central valley of california. the mg isolates were recovered from 5 different companies and 13 ranches. each company had unique mg strains. no evidence of spread of mg between companies was detected. rapd analysis of mg isolates within a ranch during an outbreak revealed only a single strain involved in each outbre ...199912968753
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on the blood characteristics of commercial egg laying hens.in two trials, the effects of an f-strain mycoplasma gallisepticum (fmg) inoculation at 12 wk of age on the blood characteristics of commercial single combed white leghorn laying hens were investigated throughout lay. variables measured in both trials were whole blood hematocrit, plasma protein (pp), and serum cholesterol, triglycerides (st), and calcium. in both trials, hematocrit at 20 wk of age was significantly increased in birds inoculated with fmg. in trial 1, st and pp were significantly ...200312967252
the complete genome sequence of the avian pathogen mycoplasma gallisepticum strain r(low).the complete genome of mycoplasma gallisepticum strain r(low) has been sequenced. the genome is composed of 996,422 bp with an overall g+c content of 31 mol%. it contains 742 putative coding dna sequences (cdss), representing a 91 % coding density. function has been assigned to 469 of the cdss, while 150 encode conserved hypothetical proteins and 123 remain as unique hypothetical proteins. the genome contains two copies of the rrna genes and 33 trna genes. the origin of replication has been loca ...200312949158
isolation and characterization of a 6/85-like mycoplasma gallisepticum from commercial laying hens.eighty-three-week-old table egg layers with swollen sinuses were presented with a history of increased mortality. serology revealed positive titers to mycoplasma gallisepticum (mg). the birds were part of a flock in which some birds had been vaccinated with 6/85 live mg vaccine at 18 wk of age. tracheal cultures were obtained from both vaccinated and unvaccinated birds within the flock. the cultures were indistinguishable from 6/85 vaccine by both random amplified polymorphic dna analysis and dn ...200312887214
mycoplasma gallisepticum-induced alterations in chicken red blood cells.incubation of mycoplasma gallisepticum with washed chicken red blood cells for 1 hr or 5 hr resulted in altered red blood cell surface morphology and perforations of the cells.200312887211
diseases of free-ranging chickens in the qwa-qwa district of the northeastern free state province of south africa.a total of 177 free-ranging chickens from 19 qwa-qwa villages were bled from wing veins over a period of 6 months (june-november 2000). serological tests indicated that 5% of chickens tested had been exposed to newcastle disease, 43% to infectious bronchitis and 63% to mycoplasma gallisepticum infection. mcmaster and visser sieve techniques were used to determine helminth and coccidia from pooled fresh faecal samples. helminths isolated in 37% of the villages investigated were heterakis, ascarid ...200312836740
cytadherence-deficient mutants of mycoplasma gallisepticum generated by transposon mutagenesis.cytadherence-related molecules of mycoplasma gallisepticum strain r-low were identified by tn4001 transposon mutagenesis with the hemadsorption (ha) assay as an indicator for cytadherence. three gm(r) ha-negative (ha(-)) colonies displaying a stable ha(-) phenotype through several successive generations in which gentamicin selection was maintained were isolated from four independent transformation experiments and characterized. southern blot analysis showed that the transposon was inserted as a ...200312819064
scanning electron microscopic studies of mycoplasma gallisepticum infection in embryonic tracheae.mycoplasma gallisepticum (mg) was used to infect chicken embryos, and scanning electron microscopy was used to examine the morphologic changes in the tracheae. tracheae harvested from embryos infected with mg for 5 days showed extensive deciliation, surface erosion, and inflammatory cell infiltration. embryonic tracheal explants infected with mg for 6 hr showed the same deciliation and surface erosion. the damage to the tracheal surface caused by mg at the embryonic stage might play a role in th ...200312713177
effects of an s6 strain of mycoplasma gallisepticum challenge at onset of lay on digestive and reproductive tract characteristics in commercial layers.mycoplasma gallisepticum (mg), a reproductive/respiratory pathogen in poultry, has been implicated in suboptimum egg production and decreased hatchability. commercial layer hens raised in a controlled environment were inoculated with the s6 strain of mg at 20 wk of age. the s6 inoculation had no effect on bird weight, egg production, digestive tract weight and length, or histopathologic lesion scores, although significant differences were noted in the lengths and weights of various portions of t ...200312713163
influences of supplemental dietary poultry fat and f-strain mycoplasma gallisepticum infection on the early performance of commercial egg laying hens.f-strain mycoplasma gallisepticum (fmg) may alter reproductive performance in layers through its effects on lipid metabolism. therefore, the influences of 1.5% supplemental dietary poultry fat (pf) and fmg infection on the early performance of commercial egg-laying hens were determined. birds were either sham- or fmg-inoculated at 12 wk, and experimental diets were initiated at 20 wk of age. body weight at 12, 20, and 24 wk, total daily egg mass, feed consumption and feed conversion at 20 and 24 ...200312710479
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on egg yolk composition in commercial egg laying hens.in two trials, the effects of f-strain mycoplasma gallisepticum (fmg) on the contents of egg yolks from commercial single comb white leghorn laying hens were investigated over a production cycle. ten hens were assigned to each of 8 (trial 1) or 16 (trial 2) negative pressure fiberglass biological isolation units. birds in half of the total units served as sham-inoculated controls, and those in the other half were inoculated with fmg at 12 wk of age. eggs were collected and yolks were harvested a ...200312710476
homologue of macrophage-activating lipoprotein in mycoplasma gallisepticum is not essential for growth and pathogenicity in tracheal organ cultures.while the genomes of a number of mycoplasma species have been fully determined, there has been limited characterization of which genes are essential. the surface protein (p47) identified by monoclonal antibody b3 is the basis for an enzyme-linked immunosorbent assay for serological detection of mycoplasma gallisepticum infection and appears to be constitutively expressed. its gene was cloned, and the dna sequence was determined. subsequent analysis of the p47 amino acid sequence and searches of ...200312670978
sensory properties of articular afferents following mycoplasma arthritis in the chicken.the physiological properties of joint capsule mechanical nociceptors of monoarthritic chickens (gallus domesticus) were studied by recording the electrical activity from single c (group iv) and a-delta (group iii) fibres dissected from the parafibular nerve. by injecting live mycoplasma gallisepticum cultures into the ankle joint a typical mycoplasma arthritis was induced which was restricted to a single joint. during the early stage of the disease (7-21 days after infection) there was histopath ...200312644261
characterisation of mycoplasma gallisepticum strains involved in respiratory disease in pheasants and peafowl.two cases of mycoplasma gallisepticum infection in different avian species in backyard gamebird operations in slovenia were investigated. in the first case, m gallisepticum was associated with severe respiratory disease with almost 20 per cent mortality in pheasants, whereas the infection was less pathogenic for chickens and turkeys reared at the same site. the m gallisepticum isolates from pheasants had a unique pmga gene sequence containing a repeat of 12 nucleotides, and they contained only s ...200312625537
phenotypic switching in mycoplasma gallisepticum hemadsorption is governed by a high-frequency, reversible point mutation.mycoplasma gallisepticum is a flask-shaped organism that commonly induces chronic respiratory disease in chickens and infectious sinusitis in turkeys. phenotypic switching in m. gallisepticum hemadsorption (ha) was found to correlate with phase variation of the gapa cytadhesin concurrently with that of the crma protein, which exhibits cytadhesin-related features and is encoded by a gene located downstream of the gapa gene as part of the same transcription unit. in clones derived from strain r(lo ...200312595441
haemagglutinins of pathogenic avian mycoplasmas.the pathogenic avian mycoplasmas, mycoplasma gallisepticum, mycoplasma synoviae, mycoplasma meleagridis, mycoplasma iowae and mycoplasma imitans, synthesize haemagglutinins that are immunogenic, variably expressed, surface proteins. the haemagglutinins of m. gallisepticum (pmga), m. synoviae (vlha) and m. imitans are lipoproteins, encoded by related multigene families that appear to have arisen by horizontal gene transfer. m. gallisepticum also has genes encoding cytadhesins in its genome but th ...200212593736
transposon mutagenesis of mycoplasma gallisepticum.there are few systems available for studying the genetics of the important avian respiratory pathogen, mycoplasma gallisepticum. these techniques are needed to develop a mechanism to study the molecular pathogenesis of m. gallisepticum. tn916 has the ability to transpose into the m. gallisepticum genome by both transformation and conjugation. in this study, peg-mediated transformation was employed for the transfer of tn916 into m. gallisepticum and create a transposon mutant library. transforman ...200312583999
chemotactic response of lymphocytes in chicken embryos infected with mycoplasma gallisepticum.a prominent feature of mycoplasma gallisepticum (mg) infection is a lymphoproliferative response at the site of infection. in this study, artificial air cells (aacs) were made in eggs containing 16-day old chicken embryos. an mg culture and supernates from mg-infected rp-9 cells, hd-11 cells and monocytes were separately deposited on the membranes of the aac. after incubation for 5 days, the eggs were opened and the aac membranes were collected for histopathological examinations. immunolabelling ...200312531685
infectious disease survey of lesser prairie chickens in north texas.lesser prairie chicken (tympanuchus pallidicinctus) abundance, like that of most grassland birds, has declined rangewide for decades. although habitat loss and degradation are likely ultimate causes for this decline, infectious agents, particularly microparasites, could be proximate contributors. no surveys of pathogenic bacteria or viruses have been published for this species. we surveyed 24 free-living lesser prairie chickens from hemphill county, texas (usa), for evidence of exposure to salmo ...200212528454
infectious disease survey of rio grande wild turkeys in the edwards plateau of texas.state wildlife agencies have translocated thousands of wild turkeys (meleagris gallopavo) since the 1930s to reestablish this species. because of threats to the domestic poultry industry and wild birds, screening for selected infectious agents has become routine since the early 1980s. one of the principal sources for rio grande wild turkeys (m. gallopavo intermedia) for translocation purposes was the edwards plateau of texas (usa). unfortunately, turkey abundance has declined in the southern edw ...200212528453
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on digestive and reproductive organ characteristics of commercial egg laying hens.experimental inoculation with the f-strain of mycoplasma gallisepticum (fmg) between 8 and 18 wk of age is known to affect reproductive performance in commercial layers. therefore, two trials were conducted to determine if changes in digestive and reproductive organ characteristics also occur in commercial laying hens infected with fmg at 12 wk of age. in trial 1, liver weight, liver lipid and moisture contents, ovary weight, ovarian follicular hierarchy, and the weights, lengths, and histologie ...200212512582
effects of genetic selection for high or low antibody response on resistance to a variety of disease challenges and the relationship of resource allocation.lines of white leghorn chickens were selectively bred for either a high (h) or low (l) antibody response to sheep erythrocytes. the parental lines, hh and ll, and reciprocal crosses, hl (sire line cited first and dam line second) and lh, were compared for their responses to various diseases. high antibody titers were associated with reduced body weight. lines and their crosses were challenged with infectious diseases. the ll line was most resistant to mycobacterium avium, whereas the hh line was ...200212495065
cloning and analysis of the gene for a major surface antigen of mycoplasma gallisepticum.myplasma gallisepticum infects a wide variety of gallineaceous birds including chickens, turkeys, and pheasants. infection occurs both horizontally and vertically. thus, control of the spread of m. gallisepticum to noninfected flocks is difficult. continual monitoring is necessary to identify infected flocks even under the most stringent infectious control practices. monitoring, however, is usually performed by measuring hemagglutination activity (ha) in serum, an insensitive and variable test. ...200212495041
Displaying items 401 - 500 of 1254