TitleAbstractYear(sorted ascending)
epitope diversity of f strain mycoplasma gallisepticum detected by flow cytometry.a culture of f strain mycoplasma gallisepticum (f-mg) that exhibited an epitope identified by monoclonal antibody (mab) 6f10 was used to inoculate leghorn hens in two different trials. in trial 1, mature hens chronically infected with f-mg were swabbed at intervals from 230 to 345 days postinoculation (pi). the f-mg isolates were tested with an agar plate fluorescent antibody (apfa) method that used a polyclonal antibody and with a flow cytometry (pc) technique that used mab 6f10. primary cultur ...19979201390
multiplex pcr for avian pathogenic mycoplasmas.mycoplasma infections are of great concern in avian medicine, because they cause economic losses in commercial poultry production. a multiplex polymerase chain reaction (pcr) was optimized to simultaneously detect four pathogenic species of avian mycoplasmas. four sets of oligonucleotide primers specific for mycoplasma gallisepticum (mg), m. synoviae (ms), m. meleagridis (mm) and m. iowae (mi) were used in the test. by using agarose gel electrophoreses for detection of the pcr-amplified dna prod ...19979232620
application of a nonlinear regression function to evaluate the kinetics of antibody response to vaccines in chicken lines divergently selected for multitrait immune evaluate the kinetics of immune response to vaccines in chickens, antibody response curves were approximated to the observed antibody ratios by using a nonlinear regression function. new parameters, the curve maximum (ymax) and the time of the maximum (tmax), were calculated. the method was applied to analyze the kinetics of the serum antibody response to mycoplasma gallisepticum (mg) and pasteurella multocida (pm) vaccines in white leghorn lines selected, in replicate, for 10 generations for ...19979276887
changing expectations in the control of mycoplasma gallisepticum.mycoplasma gallisepticum (mg) is traditionally controlled by maintaining mg-free flocks on single-age production sites and maintaining them mg-free utilizing good biosecurity and a consistent serological monitoring program. in recent years, several changes have taken place which have changed our ways about thinking about mg control. there have been significant improvements in detection methods. for example, polymerase chain reaction now represents a rapid and sensitive method for detecting the o ...19979276990
dna amplification methods for diagnosis and epidemiological investigations of avian mycoplasmosis.rapid, sensitive and specific tests that detect nucleic acid from pathogenic mycoplasmas are very attractive for the laboratory detection of infected flocks, and methods for direct detection of the four main pathogenic mycoplasmas have been developed. moreover, most avian mycoplasma species can be differentiated, according to their unique restriction fragment length polymorphism (rflp) patterns generated with different restriction enzymes. however, this method is limited to the identification of ...19979276996
molecular epidemiologic investigations of mycoplasma gallisepticum conjunctivitis in songbirds by random amplified polymorphic dna ongoing outbreak of conjunctivitis in free-ranging house finches (carpodacus mexicanus) began in 1994 in the eastern united states. bacterial organisms identified as mycoplasma gallisepticum (mg) were isolated from lesions of infected birds. mg was also isolated from a blue jay (cyanocitta cristata) that contracted conjunctivitis after being housed in a cage previously occupied by house finches with conjunctivitis, and from free-ranging american goldfinches (carduelis tristis) in north caroli ...19979284386
antibody-mediated selection of a mycoplasma gallisepticum phenotype expressing variable proteins.a variant phenotype of mycoplasma gallisepticum s6 was isolated from an in vitro antibody-culture system utilizing metabolism-inhibiting antibodies against the 64 kda lipoprotein (lp64). m. gallisepticum populations grown in medium alone or medium containing normal rabbit serum maintained expression of the parental phenotype. this paper describes the identification of proteins which undergo variable expression. several of these were integral membrane proteins, with estimated molecular masses of ...19979345761
various blood parameters in commercial hens acutely and chronically infected with mycoplasma gallisepticum and mycoplasma synoviae.two trials were conducted to study the effects of acute (trial 1) and chronic (trial 2) mycoplasma infections on differential leukocyte counts in chickens. the trials initially included either 20 (trial 1) or 40 (trial 2) 6-wk-old commercial leghorn chickens negative for antibodies to mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms). chickens were inoculated with f strain mg (fmg), ms (wvu 1853), or both. one group of chickens remained uninoculated and served as a negative control for ...19979356698
detection and identification of avian mycoplasmas by polymerase chain reaction and restriction fragment length polymorphism assay.the polymerase chain reaction (pcr) with primers complementary to the 16s rrna genes was used to detect avian mycoplasmas. a primer pair designed for the detection of human and rodent mycoplasmal species was examined for its ability to detect the most important avian mycoplasmas. after testing the respective reference strains, we found that mycoplasma iowae, mycoplasma meleagridis and mycoplasma synoviae could be detected by pcr with this primer pair, and distinction could be made among them by ...19979451458
efficacy of tilmicosin in the control of experimental mycoplasma gallisepticum infection in chickens.this study was conducted to evaluate the efficacy of 5-day, "in water" tilmicosin medication for the prevention of experimental mycoplasma gallisepticum (mg) disease in 10-day-old specific-pathogen-free (spf) chickens. birds were inoculated intratracheally and into the sinus with the mg r-p10 strain. a limited dose titration of the antibiotic over the expected effective range was included, using six groups of 60 birds each: ui: uninfected untreated group; iut: infected untreated group; it1 to it ...19979454912
the effects of f strain mycoplasma gallisepticum, mycoplasma synoviae, and the dual infection in commercial layer hens over a 44-week laying cycle when challenged before beginning of lay. i. egg production and selected egg quality each of two trials, 160 commercial pullets were separated into four treatments with four replicates of 10 chickens in each treatment. forty pullets were designated as controls and received no inoculation; 40 other pullets received f strain mycoplasma gallisepticum (fmg); an additional 40 pullets received mycoplasma synoviae (ms); and the final 40 pullets were inoculated with both fmg and ms (dual). hen-day egg production, egg weight, eggshell strength, haugh unit score, pimpling incidence, an ...19979454916
effect of drinking water containing ammonium chloride or sodium bicarbonate on mycoplasma gallisepticum isolation in experimentally infected broiler each of three trials, 150 day-old broiler chicks were eyedrop inoculated with 0.04 ml of high-passage f strain mycoplasma gallisepticum (mg) and housed in biological isolation units at 10 chicks per unit. at 4 wk of age, 50 chickens were designated as controls and remained on tap water (ph 7.30), 50 chickens were provided tap water containing 0.63% ammonium chloride (nh4cl, ph 6.91), and 50 chickens were provided tap water containing 1.26% sodium bicarbonate (nahco3, ph 8.17). fluids were sup ...19979454928
detection of mycoplasma in avian live virus vaccines by polymerase chain reaction.the polymerase chain reaction (pcr) was evaluated to detect mycoplasma contamination of avian live virus vaccines. the specificity of the primers showed that 34 strains belonging to nine species of avian mycoplasma dna could be detected. the sensitivity of pcr to detect mycoplasma dna was 10(0.2) colony forming units (cfu) of mycoplasma synoviae and 10(0.7) cfu of mycoplasma gallisepticum. when m. synoviae and m. gallisepticum were spiked into several avian live virus vaccines, pcr gave a positi ...19979467032
immunoblot examination of humoral response of chickens infected with mycoplasma gallisepticum at various ages.mycoplasma gallisepticum- and mycoplasma synoviae-free chickens were infected with 0.2 ml broth culture of m. gallisepticum strain 1226 intra air sac at 3, 14, 18, 28, 42, 49 and 65 days of age. blood samples were taken 0-5 weeks before infection and 1-6 weeks after infection (depending on age of infection). the antibody response was examined by western blot. as a control of infection, serum plate agglutination test (spa), pathological lesions, and presence of mycoplasma in air sacs were used. a ...19979481517
experimental infection of chickens with an atypical mycoplasma gallisepticum strain: comparison of diagnostic methods.fifteen chickens were inoculated with the atypical mycoplasma gallisepticum (mg) k703 strain. on different dates post inoculation, tracheal swab samples were collected for mycoplasma culture and blood samples were analysed by slide agglutination test (sa) with commercial or homologous antigen and enzyme-linked immunosorbent assay (elisa) with three different kits. results showed that mg isolation rate was low on several sampling dates. the sa with commercial antigen did not yield positive result ...19979491445
national surveillance of poultry diseases in lebanon.from 1992 to mid-1996, a national survey of poultry diseases in lebanon was conducted. this surveillance included meat breeder, layer breeder, commercial layer and chicken broiler flocks. the history, signs, lesions and laboratory tests of poultry were used in the diagnosis of prevalent poultry diseases. culture techniques were used to screen for bacterial diseases; serological techniques and, to a lesser extent, culture techniques were used to diagnose viral diseases; and both serological and c ...19979567302
epidemic mycoplasmal conjunctivitis in house finches from eastern north the winter of 1993-94, house finches (carpodacus mexicanus) with severe conjunctivitis (later shown to be caused by mycoplasma gallisepticum) were first observed in sub-urban washington d.c. (usa) and adjacent states. using a large network of volunteer observers in eastern north america, we were able to track the monthly prevalence of the disease between november 1994 and march 1997. using the information on 24,864 monthly data forms, we describe the very rapid spread of the conjunctivitis ep ...19989577773
risk factors associated with mycoplasmal conjunctivitis in house finches.observations from a citizen-based survey were used to identify potential risk factors associated with mycoplasmal conjunctivitis (mycoplasma gallisepticum) in eastern house finches (carpodacus mexicanus). between november 1994 and october 1996, 778 volunteers provided 7,224 monthly observations at residential bird feeding sites across an eight state region in the eastern usa. information collected by questionnaires included health status of house finches and four sympatric passerine species, typ ...19989577774
natural mycoplasma gallisepticum infection in a captive flock of house finches.naturally-occurring mycoplasmal conjunctivitis is described among 104 wild-caught, and initially seronegative, house finches (carpodacus mexicanus) maintained in captivity for 12 wk during november 1995 through january 1996. finches housed in three pens were monitored for clinical signs, and > or = 10 birds were euthanatized for necropsy and mycoplasma testing every 2 wk. within 2 to 4 wk following initial detection of lesions, > 50% of the birds in each of three pens developed a debilitating di ...19989577775
mycoplasma sturni from blue jays and northern mockingbirds with conjunctivitis in florida.northern mockingbirds (mimus polyglottos) and blue jays (cyanocitta cristata) in a florida (usa) wildlife care facility developed clinical signs and gross lesions suggestive of the ongoing outbreak of mycoplasma gallisepticum (mg) conjunctivitis in house finches (carpodacus mexicanus) and american goldfinches (carduelis tristis). mycoplasmal organisms were cultured from conjunctival/corneal swabs of birds with sinusitis, conjunctivitis, and/or epiphora. all of the isolates tested were identified ...19989577796
expression of two members of the pmga gene family of mycoplasma gallisepticum oscillates and is influenced by pmga-specific antibodies.certain monoclonal antibodies and polyclonal antisera directed to pmga, the major protein of mycoplasma gallisepticum, were tested for the ability to influence the surface phenotype of the cell population which resulted from their inclusion in growth medium. the polyclonal antiserum and one monoclonal antibody (mab 66) resulted in an alteration of surface phenotype; specifically, populations of cells grown either on plates or in broth cultures which contained these reagents ceased the expression ...19989596758
the effects of 1,25-dihydroxycholecalciferol and phytase on the natural phytate phosphorus utilization by laying hens.two experiments were conducted to investigate the effects of supplementing a corn-soybean layer diet with either phytase, 1,25-dihydroxycholecalciferol [1,25-(oh)2d3], or their combination. the basal diet was formulated to contain 3.00% ca and 0.33% total p. in experiment 1, 160, 56-wk-old laying hens were randomly assigned to treatment groups fed either the basal diet alone or diets supplemented with either 600 phytase units (ftu) per kilogram feed, 5 microg 1,25-(oh)2d3/kg feed, or their combi ...19989628533
characterization of mgc2, a mycoplasma gallisepticum cytadhesin with homology to the mycoplasma pneumoniae 30-kilodalton protein p30 and mycoplasma genitalium p32.a second cytadhesin-like protein, mgc2, was identified in the avian respiratory pathogen mycoplasma gallisepticum. the 912-nucleotide mgc2 gene encodes a 32.6-kda protein with 40.9 and 31.4% identity with the m. pneumoniae p30 and m. genitalium p32 cytadhesins, respectively. functional studies with reverse transcription-pcr, immunoblotting, double-sided immunogold labeling, and attachment inhibition assays demonstrated homology to the human mycoplasmal p30 and p32 cytadhesins. these findings sug ...19989632619
multigene families encoding the major hemagglutinins in phylogenetically distinct mycoplasmas.mycoplasma synoviae has two major membrane antigens, mspa and mspb, both of which are phase variable and which may be coordinately involved in adhesion of the organism to erythrocytes. a single gene (vlha) from m. synoviae was characterized, and polypeptides were expressed from nonoverlapping 5' and 3' regions in escherichia coli. the expression product of the vlha 5' region reacted with specific reagents against mspb, while that of the 3' region reacted with specific reagents against mspa. anal ...19989632627
pen trial studies on the use of live vaccines to displace virulent mycoplasma gallisepticum in chickens.groups of 10 8-wk-old chickens that had been vaccinated 4 wk previously with the f strain, ts-11, or 6/85 strain of mycoplasma gallisepticum (mg) were challenged by placing them in contact with 20 chickens that had been previously infected with the virulent r strain of mg. each month, the 10 oldest chickens were removed from each pen and replaced with 10 vaccinated chickens to return the total number of chickens in each pen to 30. chickens were bled and cultured for mg prior to contact challenge ...19989645321
potential for transmission of the finch strain of mycoplasma gallisepticum between house finches and chickens.although mycoplasma gallisepticum (mg) is established in house finch (carpodacus mexicanus) populations in at least 33 states, the potential risk of mg introduction to domestic poultry by infected finches currently is unknown. the objectives of this study were to determine if chickens could be infected with the finch strain of mg via direct, across-wire, and proximity (across-room) contact with naturally infected house finches and to determine if house finches could be infected through direct co ...19989645326
serologic incidence of some diseases in kansas wild turkeys.wild turkeys (meleagris gallopavo, n = 1164) were tested for mycoplasma gallisepticum, mycoplasma meleagridis, mycoplasma synoviae, and salmonella pullorum from 1990 to 1997. although 3.3% of the turkeys were suspect for one or more diseases, only 0.9% were serologically positive for m. gallisepticum. these 11 positives were all from one country in south-central kansas.19989645333
eradication of live f strain mycoplasma gallisepticum vaccine using live ts-11 on a multiage commercial layer farm.subsequent to use of a live mycoplasma gallisepticum (mg) vaccination program, the f strain of mg had been circulating on a commercial layer farm since 1981. in 1994, the ts-11 strain was introduced on the farm; each new placement flock was vaccinated by eyedrop with ts-11 for one production cycle, and then all subsequent placement flocks were left unvaccinated. birds were monitored by culture and serology before and after vaccination. mg isolates were characterized by random amplified polymorph ...19989645335
pasteurella multocida infection involving cranial air spaces in white leghorn 18-wk-old pullets from a commercial layer flock experiencing increased mortality associated with neurologic and respiratory symptoms were submitted to the california veterinary diagnostic laboratory system at the turlock branch for necropsy. clinical signs included depression, torticollis, swollen eyelids, conjunctivitis, and sinusitis. meningoencephalitis and suppurative inflammation of the cranial air spaces were found on histopathology. the brain, sinuses, and air spaces of the cranium ...19989645337
evaluation of an enrofloxacin-treatment program against mycoplasma gallisepticum infection in broilers.three chicken broiler breeder flocks, 7 months of age, were confirmed to have mycoplasma gallisepticum (mg) infection, based on culture of tracheal swabs. a total of fifty-five 7-day-old embryos from the three mg-positive flocks had an average 27.4% prevalence of mg-infection in their vitelline membrane. sixty randomly selected mg isolates (30 from individual tracheas of breeders and another 30 from individual vitelline membrane of embryos) were highly sensitive in vitro to enrofloxacin (100%). ...19989646333
comparison of serological tests for detection of mycoplasma gallisepticum antibodies in eggs and chicks hatched from experimentally infected hens.specific pathogen free hens and males were experimentally infected with mycoplasma gallisepticum. eggs were then collected, and a part was incubated and set for hatching. mycoplasma cultures were performed on infected adults and antibodies to mg were analysed by use of slide agglutination (sa) test and commercial elisa tests on adults and chicks sera and on yolks from non incubated eggs. both elisa tests could detect antibodies in yolks from non incubated eggs laid three weeks after infection. s ...19989646451
efficacy of difloxacin in growing broiler chickens for the control of infection due to pathogenic mycoplasma gallisepticum.chickens 14 days old were experimentally inoculated with mycoplasma gallisepticum (mg) r-p10 strain. after development of respiratory symptoms, birds were left unmedicated or medicated for 5 consecutive days with difloxacin 5, 7.5 or 10 mg/kg body weight per day or enrofloxacin at the dose level of 10 mg/kg body weight per day. evaluation of efficacy was based on body weight, symptoms, post-mortem findings, re-isolation of mg and serology. results indicated that under the conditions of this expe ...19989673582
identification and characterization of hu protein from mycoplasma gallisepticum.a hypothetical orf of mycoplasma gallisepticum with a putative 99-amino-acid product (orf99) was noted previously in the upstream region from the type ii topoisomerase gene. the amino acid sequence shows weak homology with the escherichia coli histone-like protein hu. to identify and characterize the protein product of orf99, we prepared mouse antiserum against recombinant gst-orf99 fusion protein. the antiserum reacted with an 11-kda peptide in the crude cell extract of m. gallisepticum, indica ...19989705829
mycoplasmas in the etiology of multifactorial respiratory disease.the avian mycoplasmas pathogenic for commercial poultry, mycoplasma gallisepticum and mycoplasma synoviae in chickens and turkeys, and mycoplasma meleagridis and mycoplasma iowae in turkeys are egg-transmitted infections and exhibit wide variations in clinical manifestations. mycoplasma gallisepticum strains vary widely in virulence, tissue tropism, and antigenic makeup and have the ability to alter the expression of major surface antigenic proteins. although less well studied, strains of m. syn ...19989706080
the subunit b of the f0f1-type atpase of the bacterium mycoplasma pneumoniae is a lipoprotein.the dna sequence analysis of the f0f1-atpase operon of the bacterium mycoplasma pneumoniae predicted that the subunit b, encoded by the gene atpf, is a lipoprotein of the murein lipoprotein type of escherichia coli. here we experimentally verify this prediction by metabolic labeling of subunit b with [14c]palmitic acid and by in vivo interfering with the processing of the prolipoprotein form of subunit b by the antibiotic globomycin, a specific inhibitor of the signal peptidase ii. our results s ...19989733782
dna amplification methods for diagnosis and epidemiological investigations of avian mycoplasmosis.this review describes some applications of dna amplification methods for diagnosis or epidemiological investigations of avian mycoplasmosis. tests for direct detection of pathogenic mycoplasmas have been developed. moreover, most avian mycoplasma species can be differentiated, according to their unique restriction fragment length polymorphism (rflp) patterns generated after digestion of pcr products with different restriction enzymes. in order to characterize isolates below the species level, pc ...199818483959
pathogenicity of in vivo-passaged mycoplasma imitans in turkey poults in single infection and in dual infection with rhinotracheitis virus.mycoplasma imitans (mim) is a close relative of mycoplasma gallisepticum (mg), but has been isolated from ducks, geese and partridge. in order to investigate its potential pathogenicity for turkeys a uk isolate of mim from a partridge with sinusitis was first passaged through turkey poults and then assessed for pathogenicity in turkey embryo tracheal organ cultures (tocs) and in one-day-old turkey poults with or without turkey rhinotracheitis virus (trtv). mim appeared to gain virulence on passa ...199818483968
assessment of the efficacy of tilmicosin as a treatment for mycoplasma gallisepticum infections in chickens.this study involved two experiments which examined the efficacy of 'in water' tilmicosin medication for the treatment of experimental mycoplasma gallisepticum (mg) disease. the first experiment investigated tilmicosin concentrations of 50, 100, 200 and 400 mg/l administered for 5 days. in the second experiment, dose levels of 50, 75 and 100 mg/l tilmicosin administered for either 3 or 5 days were investigated. the first experiment suggested that tilmicosin was effective in reducing the incidence ...199818483985
lymphoproliferative responses of specific-pathogen-free chickens to mycoplasma gallisepticum strain pg31.mycoplasma gallisepticum (mg) is one of the aetiologic agents of chronic respiratory disease in chickens and infectious sinusitis in turkeys. we investigated humoral and cellular immune mechanisms following experimental infection with four different strains of mg. peripheral blood leukocytes (pbl) obtained from chickens were examined for proliferation using antigen preparations of whole cell mg as stimuli in vitro. a consistent lymphoproliferative response was observed against the homologous who ...199818483998
pathogenicity of mycoplasma gallisepticum and mycoplasma imitans in red-legged partridges (alectoris rufa).groups of 3-day-oid red-legged partridges were infected intranasally either with the s6 strain of m. gallisepticum or with an m. imitans strain from a partridge with sinusitis. starting 6-8 days post-infection (p.i.) birds in both groups developed signs of depression, nasal exudation, tracheal rales, sneezing, gasping, head shaking, watery eyes and eye scratching. the most outstanding feature was bilateral swelling of the infraorbital sinuses. morbidity reached 100% in the m. gallisepticum infec ...199818484030
antibody response detected by immunoblot in respiratory tract washings of chickens after infection with mycoplasma gallisepticum.two experiments were conducted to test the sensitivity of western blotting for detection of m. gallisepticum antibodies in respiratory washings and sera of infected chickens by mouse monoclonal antibodies to chicken igg, igm and iga. in the first experiment, birds infected at 10 days of age were examined 2 weeks later. in the respiratory washings, iga antibodies reacted with eight polypeptides of m. gallisepticum, while igm and igg reacted with three. in the serum iga antibodies were not detecte ...199818484042
development of antibiotic resistance in mycoplasma gallisepticum in vitro.the results of in vitro tests for induction of antibiotic resistance in some strains of mycoplasma gallisepticum are reported. the number of passages required to induce resistance varied considerably between different antibiotics. in two groups of tests, with different strains of m. gallisepticum, resistance (>/= 1 mg/ml) to streptomycin appeared after two to three passages, to erythromycin and spiramycin after five to eight passages, to tylosin after nine to eleven and to enrofloxacin after eig ...199818484048
a comparison of a commercial pcr-based test to culture methods for detection of mycoplasma gallisepticum and mycoplasma synoviae in concurrently infected chickens.the suitability of commercial pcr-based test kits for the detection of either mycoplasma gallisepticum (mg) or m. synoviae (ms) was compared to detection by culture. the mg and ms kit detected six and five homologous strains respectively in broth cultures and there were no reactions with thirteen het-erologous species including m. imitans, a species phylogenetically closely related to mg. tracheal and lung/air-sac swabs were collected from twenty 17-week-old commercial pullets which were seropos ...199818484270
a protein (m9) associated with monoclonal antibody-mediated agglutination of mycoplasma gallisepticum is a member of the pmga family.a 62-kda cell surface antigen (m9) of mycoplasma gallisepticum pg31 that mediates antibody-induced agglutination of the organism was purified and subjected to n-terminal amino-acid sequencing. a 999-bp region of the cdna encoding the m9 protein was generated by reverse transcription-pcr, and its nucleotide sequence was determined. pcr primers based on this sequence were used to screen a genomic dna library of pg31. a full-length m9 protein-encoding gene was isolated and sequenced, revealing 96% ...19989784576
expression of the pmga genes of mycoplasma gallisepticum is controlled by variation in the gaa trinucleotide repeat lengths within the 5' noncoding regions.we analyzed the segment of dna which contains the expressed pmga gene from one strain of mycoplasma gallisepticum in normal (strain s6) cells and in cells in which pmga1.1 gene expression had ceased as a consequence of in vitro culture in the presence of pmga1. 1-specific antibodies. sequence analysis of isolates lacking pmga1.1 expression revealed that this gene, which is typically expressed, exhibited sequence changes within a region 5' to its promoter. specifically, pmga1.1(+) cells contained ...19989826362
molecular and biochemical analysis of a 105 kda mycoplasma gallisepticum cytadhesin (gapa).the identification of a gene (gapa) from mycoplasma gallisepticum with homology to the p1 cytadherence gene of mycoplasma pneumoniae is reported. the gapa gene is a 2895 bp orf encoding a protein with a molecular mass of 105 kda. nucleotide sequence analysis of the gapa gene revealed 45% homology to the m. pneumoniae p1 gene, 46% homology to the mycoplasma genitalium mgpa gene and 47% homology to the mycoplasma pirum p1-like protein gene. it has a 64 mol % a+t content compared to 46, 60 and 72 m ...19989846732
safety of a temperature-sensitive clone of mycoplasma synoviae as a live vaccine.a temperature-sensitive (ts+) clone derived from the australian mycoplasma synoviae (ms) field isolate 86079/7ns was produced by chemical mutagenesis with n-methyl-n'-nitro-n-nitrosoguanidine and assessed for safety as a live vaccine. this clone, designated ms-h, was assessed for pathogenicity in three different models with air sac lesions as the criterion. no air sac lesions were observed when ms-h was administered to specific-pathogen-free hybrid white leghorn (hwl) chickens by eyedrop at 10 t ...19989876835
in vitro and in vivo comparisons of valnemulin, tiamulin, tylosin, enrofloxacin, and lincomycin/spectinomycin against mycoplasma gallisepticum.the minimum inhibitory concentrations (mics) for valnemulin, tiamulin, enrofloxacin, tylosin, and lincomycin/spectinomycin were determined for a virulent strain of mycoplasma gallispeticum (mg). at the initial reading, the lowest mics were seen with valnemulin and tiamulin, followed by tylosin, enrofloxacin, and a relatively high mic for lincomycin/spectinomycin. at the final reading, at 14 days, a similar pattern was obtained, with valnemulin giving the lowest mic (< 0.008 mg/ml). the same stra ...19989876842
complementary randomly amplified polymorphic dna (rapd) analysis patterns and primer sets to differentiate mycoplasma gallisepticum strains.randomly amplified polymorphic dna (rapd) analysis was used to differentiate 7 strains of mycoplasma gallisepticum. six commercially available primers or primer combinations were screened for their ability to differentiate vaccine and type strains. although major and minor bands were produced with each primer, many of the primers were unsuitable for strain differentiation. the use of primer 6 and combined primers 3 and 4 resulted in complementary rapd banding patterns for each m. gallisepticum s ...199910098688
the characterization of mycoplasma synoviae ef-tu protein and proteins involved in hemadherence and their n-terminal amino acid abundant cytoplasmic 43-kda protein from mycoplasma synoviae, a major pathogen from poultry, was identified as elongation factor tu. the n-terminal amino acid sequence (akldfdrskehvnvgtighv) has 90% identity with the sequence of the mycoplasma hominis elongation factor tu protein. monoclonal antibodies reacting with the m. synoviae elongation factor tu protein also reacted with 43-kda proteins from the avian mycoplasma species mycoplasma gallinarum, mycoplasma gallinaceum, mycoplasma pullorum ...199910220885
the effects of f strain mycoplasma gallisepticum, mycoplasma synoviae, and the dual infection in commercial layer hens over a 44-week laying cycle when challenged before beginning of lay. ii. egg size each of two trials, 160 commercial pullets were separated into four treatments with four replicates of 10 chickens in each treatment. forty pullets were designated as controls and received no inoculation; 40 pullets received f strain mycoplasma gallisepticum (fmg); an additional 40 pullets received mycoplasma synoviae (ms); and the final 40 pullets were inoculated with both fmg and ms (dual). all inoculations occurred at 10 wk of age. eggs from all treatments were collected daily, monday-thur ...199910396648
mycoplasma synoviae surface protein mspb as a recombinant antigen in an indirect elisa.mycoplasma synoviae is a poultry pathogen causing respiratory disease and synovitis. a number of serological assays have been developed for diagnosis of m. synoviae infection; however, they lack sensitivity and/or are prone to false-positive reactions. using a combination of pcr and expression cloning, four overlapping regions (regions 1-4) of the surface antigen mspb of m. synoviae wvu-1853 were expressed in a bacterial expression system. immunostaining of the resultant polypeptides with chicke ...199910463175
a gene family in mycoplasma imitans closely related to the pmga family of mycoplasma gallisepticum.the avian pathogen mycoplasma gallisepticum possesses a large gene family encoding lipoproteins which function as haemagglutinins. representative species of the pneumoniae phylogenetic group of mycoplasmas were examined for the presence of genes homologous to members of this multigene family. antisera against the pmga1.1 lipoprotein recognized a 35 kda protein in mycoplasma imitans, but did not recognize proteins of mycoplasma genitalium, mycoplasma pneumoniae, mycoplasma pirum, mycoplasma penet ...199910463176
effects of age at inoculation and induced molt on the recovery of mycoplasma gallisepticum from layer experiment was conducted to determine the effects of age at inoculation and induced molt on the reisolation of mycoplasma gallisepticum (mg) from commercial leghorn hens that had been eyedrop-inoculated with f strain mg at either 10 or 66 wk of age. chickens were maintained in biological isolation units from 10 wk of age through 78 wk of age. at 70 wk of age (premolt), hens were swabbed, cultured for mg, and molted. swabs were taken both at the end of molt (postmolt [74 wk]) and again 4 wk la ...199910494421
the comparison of an aqueous preparation of tilmicosin with tylosin in the treatment of mycoplasma gallisepticum infection of turkey poults.a virulent strain of mycoplasma gallisepticum (mg) was used to infect groups of 40 2-day-old poults kept in separate pens of 10 each. of the six groups, three were treated with separate concentrations of tilmicosin, one was treated with tylosin, one remained untreated, and a final group was not infected and not treated. mortality, clinical signs, and gross lesions were significantly less (p < 0.001) in the uninfected and infected medicated groups than in the infected unmedicated group. also, the ...199910494422
survey of pathogens and blood parasites in free-living determine the disease prevalence of free-living passerines, 1709 passerines were sampled from 38 different field sites in ohio. choanal and cloacal swabs were collected from each bird and cultured for the presence of pasteurella multocida, salmonella spp., and escherichia coli by standard microbiologic techniques. in addition, the serum from each bird was analyzed for the presence of antibodies to mycoplasma gallisepticum, mycoplasma synoviae, newcastle disease virus, and avian influenza viru ...199910494426
field investigation of mycoplasma gallisepticum infections in house finch (carpodacus mexicanus) eggs and nestlings.we conducted a field study to investigate the occurrence of mycoplasma gallisepticum (mg) in eggs and nestlings from nests of house finches (carpodacus mexicanus). forty-three nests were located between the months of april and august 1998 and were followed with one to three sampling efforts. vitelline membrane of fresh eggs, whole embryos, or swabs from the choanal cleft or conjunctiva of nestlings were inoculated into mycoplasma broth for mg isolation and polymerase chain reaction (pcr) testing ...199910494429
pathogenic effects on domestic poultry of a mycoplasma gallisepticum strain isolated from a wild house finch.mycoplasma gallisepticum (mg) has been isolated from wild house finches. the pathogenic effects of mg finch strain (k4058) and mg r-strain were compared after exposure of chickens and turkeys. gross and histologic lesions, reisolation of the organism, serology, and clinical disease were evaluated. milder histologic and gross lesions, in addition to lower serologic titers, occurred in birds inoculated with the finch strain. mortality, concurrent with clinical and gross respiratory signs and lesio ...199910611979
detection of mycoplasma gallisepticum and mycoplasma synoviae antibodies in the sera of indigenous chickens by rapid serum agglutination test at mmopane, gaborone, botswana.the mean flock size was ten chickens per rural farmer. antibodies to mycoplasma gallisepticum and mycoplasma synoviae were detected in 57.88% and 67.33% of the chicken sera respectively.199910689706
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
pathogenicity of mycoplasma imitans in mixed infection with infectious bronchitis virus in chickens.mycoplasma imitans (mim) has been isolated from ducks, geese and partridges, and is closely related to mycoplasma gallisepticum (mg). the pathogenicity of mim for chicks was investigated in single and mixed infections with infectious bronchitis virus (ibv) by giving ibv strain m41 at 1-day-old and mim 2 days later. single infections with ibv or mim were also performed. no clinical signs or gross lesions were seen in chicks infected with mim or uninfected control chicks, but they were seen in the ...199926915378
experiences with multispecies polymerase chain reaction and specific oligonucleotide probes for the detection of mycoplasma gallisepticum and mycoplasma synoviae.amplified fragments of the rdna coding for 16s rrna of mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) were blotted on nylon membranes, followed by dot-blot detection with two species-specific digoxigenin-(dig)-labeled oligonucleotide probes. the sensitivity and specifity of the tests were determined in titration studies with purified homologous and heterologous dna. with the detection protocol used, the msyv8/31 probe showed 100% specifity for ms, while both mg and the related specie ...199926905489
protective effect of two mycoplasma gallisepticum protein fractions affinity purified with monoclonal antibodies.two protein fractions of mycoplasma gallisepticum (mg) were affinity purified with monoclonal antibodies a3 and b3, and tested for protective capacity in chickens. one fraction, designated mgp1, appeared as a doublet of 64 and 62kda bands in sodium dodecyl sulphate-polyacrylamide gel electrophoresis gels, while mgp2 consisted of five polypeptides (64, 56, 47, 45 and 43 kda). the molecular mass, haemagglutination activity and matching amino acid sequence of mgp1 suggest that it is identical to pm ...200019184824
a novel mechanism for control of antigenic variation in the haemagglutinin gene family of mycoplasma synoviae.high-frequency phase and antigenic variation of homologous lipoprotein haemagglutinins has been seen in both the major avian mycoplasma pathogens, mycoplasma synoviae and mycoplasma gallisepticum. the expression and, hence, antigenic variation of the pmga gene family (encoding these lipoproteins in m. gallisepticum) is controlled by variation in the length of a trinucleotide repeat motif 5' to the promoter of each gene. however, such a mechanism was not detected in preliminary observations on m. ...200010692167
use of an alkaline phosphatase-labelled probe for the detection of mycoplasma synoviae in chickens.short nucleotides directly labelled to alkaline phosphatase (snap probes) are an interesting alternative to digoxigenin-labelled probes (dig probes), because they reduce the number of steps necessary in dot blots for the detection of dna or amplificate. this study examined the questions whether a snap probe might not only save time, but also increase the sensitivity of another pcr-based dna probe test using a digoxigenin probe. amplificates obtained by multispecies polymerase chain reaction (pcr ...200010780170
density-dependent decline of host abundance resulting from a new infectious disease.although many new diseases have emerged within the past 2 decades [cohen, m. l. (1998) brit. med. bull. 54, 523-532], attributing low numbers of animal hosts to the existence of even a new pathogen is problematic. this is because very rarely does one have data on host abundance before and after the epizootic as well as detailed descriptions of pathogen prevalence [dobson, a. p. & hudson, p. j. (1985) in ecology of infectious diseases in natural populations, eds. grenfell, b. t. & dobson, a. p. ( ...200010792031
mycoplasmal conjunctivitis in songbirds from new york.a field study was conducted to determine the prevalence of conjunctivitis and mycoplasma gallisepticum (mg) infections in house finches (carpodacus mexicanus) and other songbirds common to bird feeders in tompkins county (new york, usa). eight hundred two individuals of 23 species and nine families of birds were captured and given physical examinations during the 14 mo study beginning in february 1998. clinical conjunctivitis (eyelid or conjunctival swelling, erythema, and discharge) was observe ...200010813607
identification and expression of a mycoplasma gallisepticum surface antigen recognized by a monoclonal antibody capable of inhibiting both growth and order to identify antigenic proteins of mycoplasma gallisepticum, monoclonal antibodies (mabs) against virulent m. gallisepticum r strain were produced in mice. mab 35a6 was selected for its abilities to inhibit both growth and metabolism of m. gallisepticum in vitro. the mab recognized a membrane protein with an apparent molecular mass of 120 kda. the corresponding gene, designated the mgc3 gene, was cloned from an m. gallisepticum genomic dna expression library and sequenced. the mgc3 gene ...200010816462
lymphocytic infiltration in the chicken trachea in response to mycoplasma gallisepticum infection.a prominent feature of disease induced by mycoplasma gallisepticum is a lymphoproliferative response in the respiratory tract. although this is also seen in other mycoplasma infections, including mycoplasma pneumoniae, the phenotype of the lymphocytes infiltrating the respiratory tract has not been determined. in this study, the numbers and distribution of lymphocytes in the tracheas of chickens infected with a virulent strain of m. gallisepticum were examined. three groups of chickens were expe ...200010832650
molecular characterization of the mycoplasma gallisepticum pvpa gene which encodes a putative variable cytadhesin protein.a putative cytadhesin-related protein (pvpa) undergoing variation in its expression was identified in the avian pathogen mycoplasma gallisepticum. the pvpa gene was cloned, expressed in escherichia coli, and sequenced. it exhibits 54 and 52% homology with the p30 and p32 cytadhesin proteins of the human pathogens mycoplasma pneumoniae and mycoplasma genitalium, respectively. in addition, 50% homology was found with the mgc2 cytadhesin of m. gallisepticum and 49% homology was found with a stretch ...200010858209
in vitro cell invasion of mycoplasma gallisepticum.the ability of the widespread avian pathogen mycoplasma gallisepticum to invade cultured human epithelial cells (hela-229) and chicken embryo fibroblasts (cef) was investigated by using the gentamicin invasion assay and a double immunofluorescence microscopic technique for accurate localization of cell-associated mycoplasmas. the presence of intracellular mycoplasmas in both cell lines was clearly demonstrated, with organisms entering the eukaryotic cells within 20 min. internalized mycoplasmas ...200010858241
[determination and analysis of the nucleotide sequence of a segment of a mycoplasma gallisepticum strain a5969 chromosome, containing operons s10 and rrn23-5]. 200010867916
immunohistochemical detection of mycoplasma gallisepticum antigens in turkey respiratory avidin-biotin-immunoperoxidase diagnostic test was developed to facilitate rapid identification of mycoplasma gallisepticum in respiratory tissues of turkeys. this procedure used polyclonal primary antibodies produced in rabbits. turkeys were inoculated into the infraorbital sinus and trachea with the r strain of m. gallisepticum, mycoplasma synoviae, mycoplasma meleagridis, or frey's media. the outer walls of the infraorbital sinuses, lungs, and tracheas were collected and fixed in either 10 ...200010879921
phenotypic variation of mycoplasma iowae surface antigen.the diseases caused by mycoplasmas are generally chronic and persistent and apparently occur notwithstanding a host immune response. the ability to evade the host immune response is facilitated by phenotypic variation in the mycoplasma surface components. the avian mycoplasmas mycoplasma gallisepticum and mycoplasma synoviae have both been previously described to be able to switch their surface antigens, and recent evidence indicates that m. gallisepticum could switch surface antigens under natu ...200010879924
avian mycoplasmosis (mycoplasma gallisepticum).mycoplasma gallisepticum is the most economically significant mycoplasma pathogen of poultry, and has a world-wide distribution. in common with other mycoplasmas, m. gallisepticum is minute in size with minimal genetic information and with a total lack of a bacterial cell wall. these properties are reflected in a high degree of interdependence between m. gallisepticum and the host animal, and in the fastidious nature of the organism in vitro. strains of m. gallisepticum differ markedly with resp ...200010935272
guidelines and recommendations for antimicrobial minimum inhibitory concentration (mic) testing against veterinary mycoplasma species. international research programme on comparative mycoplasmology.the absence of standardised procedures for minimum inhibitory concentration (mic) testing of antimicrobial agents against veterinary mycoplasma and ureaplasma species (mollicutes) has made it difficult to compare results originating from different laboratories. this report, prepared on behalf of the international research programme on comparative mycoplasmology (irpcm), offers guidelines and recommendations for veterinary mic testing of these organisms in an effort to rectify this problem. the s ...200010958240
transposon mutagenesis of mycoplasma gallisepticum by conjugation with enterococcus faecalis and determination of insertion site by direct genomic sequencing.few genetic systems for studying mycoplasmas exist, but transposon tn916 has been shown to transpose into the genomes of some species and can be used as an insertional mutagen. in the current study, the ability of enterococcus faecalis to serve as a donor for the conjugative transfer of transposon tn916 into the genome of the avian pathogen mycoplasma gallisepticum strain pg31 was examined. transconjugants were obtained at a frequency of > or =6 x 10(-8) per recipient cfu. to determine the trans ...200010964629
pmga phenotypic variation in mycoplasma gallisepticum occurs in vivo and is mediated by trinucleotide repeat length variation.chickens were infected with a pathogenic strain of mycoplasma gallisepticum, and the expression of pmga, the major surface protein, was inferred by examination of colonies from ex vivo cells. within 2 days postinfection, 40% of cells had ceased the expression of the original pmga surface protein (pmga1.1), and by day 6, the majority of recovered cells were in this category. the switch in pmga phenotype which had occurred in vivo was reversible, since most colonies produced from ex vivo progenito ...200010992515
morphologic observations on respiratory tracts of chickens after hatchery infectious bronchitis vaccination and formaldehyde fumigation.the histologic changes in the respiratory tracts of chickens were evaluated after hatchery fumigation with 40% formaldehyde vapors and vaccination against infectious bronchitis virus with live attenuated vaccine (massachusetts serotype). one-day-old chickens were housed in four isolation units in controlled environmental conditions, fed and watered ad libitum, and separated into four groups: 1) fumigated and vaccinated birds (fv group); 2) nonfumigated and vaccinated birds (nfv group); 3) fumiga ...200011006997
the effects of ts-11 strain mycoplasma gallisepticum vaccination in commercial layers on egg production and selected egg quality mycoplasma gallisepticum (mg) vaccines have been usda approved and licensed for use in commercial layer chickens since 1988; however, egg production and egg quality data exist only for the f strain of mg. information pertinent to the effects of ts-11 mg on egg and eggshell quality parameters, as well as egg size distribution, is lacking. in this study, pullets were inoculated at 10 wk of age with ts-11 strain mg and placed in biological isolation units at 10 birds/unit. hen-day egg producti ...200011007009
analysis of cytadherence-deficient, gapa-negative mycoplasma gallisepticum strain r.comparison of the phenotypic expression of mycoplasma gallisepticum strain r low (passage 15) to that of strain r high (passage 164) revealed that three proteins, i.e., the cytadhesin molecule gapa, a 116-kda protein (p116), and a 45-kda protein (p45), are missing in strain r high. sequence analysis confirmed that the insertion of an adenine 105 bp downstream of the gapa translational start codon resulted in premature termination of translation in r high. a second adenine insertion had also occu ...200011083776
serological monitoring on layer farms with specific pathogen-free monitor the existence of avian pathogens in laying chicken flocks, specific pathogen-free (spf) chickens were introduced into two layer farms and reared with laying hens for 12 months. spf chickens were bled several times after their introduction and examined for their sero-conversion to avian pathogens. as a result, antibodies to eight or ten kinds of pathogens were detected in spf chickens on each farm. antibodies to infectious bronchitis virus (ibv), avian nephritis virus, mycoplasma galli ...200011193353
infection and immunity in broiler chicken breeders vaccinated with a temperature-sensitive mutant of mycoplasma gallisepticum and impact on performance of offspring.a comparison of infection and immunity to mycoplasma gallisepticum (mg) in broiler chicken breeders vaccinated with a temperature-sensitive mutant of mg versus nonvaccinated chickens, and the impact on the performance of their offspring was conducted. infection and immunity in breeders were assessed by culture and enzyme-linked immunoassay, respectively. however, performance in their offspring was assessed by studying mg infection in embryos, occurrence of infection titers to mg in relation to m ...200011194034
maintenance of a captive flock of house finches free of infection by mycoplasma gallisepticum.since the beginning of an epidemic of conjunctivitis in wild house finches caused by mycoplasma gallisepticum (mg), all captive colonies established by capturing free-ranging house finches from the eastern population have also either been infected at the time of capture or developed infection shortly after capture. in an attempt to avoid this infection in captive flocks being maintained for studies of the finches' behavior and ecology, we compared two different flock management strategies and we ...200011195652
health status of northern bobwhite quail (colinus virginianus) in eastern kansas.the health status of wild northern bobwhite quail (colinus virginianus) from lyon county, kansas, was evaluated by conducting comprehensive health assessments on 25 birds. gross lesions indicative of avian pox, ulcerative enteritis, and quail bronchitis were not present. serologic tests for antibodies to salmonella pullorum, salmonella gallinarum, pasteurella multocida, mycoplasma gallisepticum, mycoplasma synoviae, and avian adenoviruses were all negative. intestinal coccidia (eimeria spp.) wer ...200011195653
serologic survey of slaughter-age ostriches (struthio camelus) for antibodies to selected avian pathogens.serum samples from 163 slaughter-age ostriches (struthio camelus) in ohio and indiana were tested for antibodies to avian influenza virus (aiv), newcastle disease virus (ndv), paramyxovirus (pmv) 2, pmv3, pmv7, infectious bursal disease virus (ibdv), bordetella avium, mycoplasma synoviae, mycoplasma gallisepticum, ornithobacterium rhinotracheale, salmonella pullorum, salmonella gallinarum, and salmonella typhimurium. one ostrich had antibodies to aiv h5n9, 57% of the ostriches had antibodies to ...200011195659
mycoplasma gallisepticum -induced release of macrophage inflammatory protein-1 beta from chicken monocytes-macrophages.chicken monocytes and a macrophage-like cell line were used to determine the presence of macrophage inflammatory protein-1 beta (mip-1 beta). rna was extracted from these cells and subjected to reverse transcription with an anti-sense primer specific for the whole length of the mip-1 beta cdna. after a polymerase chain reaction to amplify the cdna, a 200 bp gene product was detected, which corresponded to the molecular weight of the mip-1 beta. the culture supernate of these cells did not have t ...200010627389
gaa trinucleotide repeat region regulates m9/pmga gene expression in mycoplasma gallisepticum.mycoplasma gallisepticum, the cause of chronic respiratory infections in the avian host, possesses a family of m9/pmga genes encoding an adhesin(s) associated with hemagglutination. nucleotide sequences of m9/pmga gene family members indicate extensive sequence similarity in the promoter regions of both the transcribed and silent genes. the mechanism that regulates m9/pmga gene expression is unknown, but studies have revealed an apparent correlation between gene expression and the number of tand ...200010639457
antibodies to selected disease agents in translocated wild turkeys in california.wild turkeys (meleagris gallopavo) trapped within california (n = 715) or imported into california from other states (n = 381) from 1986 to 1996 were tested for exposure to certain disease agents. prevalence of antibody to mycoplasma gallisepticum, mycoplasma meleagridis, salmonella pullorum, salmonella typhimurium, newcastle disease virus, and avian influenza virus was low (0-4%) for wild turkeys trapped within california. with the exception of antibody prevalence to m. meleagridis of 33%, the ...200010682760
sequence polymorphisms within the pmga genes and pmga antigenic variants in mycoplasma gallisepticum.antigenic variants of mycoplasma gallisepticum major surface lipoprotein, pmga, are encoded by a large gene family. in this study sequence analyses of the pcr-amplified pmga genes showed two types of sequences similar to the pmga1.2 gene in m. gallisepticum strains. they differed in the sequence encoding a proline-rich region (prr) at the n-terminus of the pmga protein. the type a genes had sequences similar to the published pmga1.2 gene sequence of strain s6, whereas the type b genes lacked the ...200010689179
host range and dynamics of mycoplasmal conjunctivitis among birds in north epidemic of conjunctivitis among house finches (carpodacus mexicanus) caused by mycoplasma gallisepticum (mg) bacterial infections was first described in 1994. the disease exhibits high primary host specificity, but has been isolated from a limited number of secondary avian hosts at various times and locations. we used records from the house finch disease survey, a continent-wide, volunteer monitoring project, to document the host range of conjunctivitis in birds at feeding stations and to in ...200111272507
characterization of the mycoplasmal conjunctivitis epizootic in a house finch population in the southeastern epidemiological study of the prevalence of mycoplasmal conjunctivitis in the house finch (carpodacus mexicanus) was conducted in auburn (alabama, usa) between march 1998 and february 1999. clinical disease was observed in 4% of the 1,214 finches trapped and examined. this rate is comparable to the average annual prevalence observed in this population since 1996, although the prevalence of clinical disease observed in the peak months of september through november was lower than in previous yea ...200111272508
diagnosis and treatment of conjunctivitis in house finches associated with mycoplasmosis in ongoing outbreak of mycoplasma gallisepticum-associated conjunctivitis in house finches (carpodacus mexicanus) that began in 1994 in the eastern united states has been spreading westward. house finches presenting with the clinical signs of m. gallisepticum-associated conjunctivitis were first seen at the wildlife rehabilitation center of minnesota (minnesota, usa) in july of 1996, and 42 cases were admitted from 26 december 1996 to 10 august 1997. a nested pcr was designed for sensitive and s ...200111310874
molecular variability of the adhesin-encoding gene pvpa among mycoplasma gallisepticum strains and its application in diagnosis.mycoplasma gallisepticum is an important pathogen of chickens and turkeys that causes considerable economic losses to the poultry industry worldwide. the reemergence of m. gallisepticum outbreaks among poultry, the increased use of live m. gallisepticum vaccines, and the detection of m. gallisepticum in game and free-flying song birds has strengthened the need for molecular diagnostic and strain differentiation tests. molecular techniques, including restriction fragment length polymorphism of ge ...200111326008
characterization of mycoplasma gallisepticum infection in captive house finches (carpodacus mexicanus) in 1998.since 1995, the epidemic of mycoplasmal conjunctivitis in eastern house finches has affected the auburn, al, house finch population. to better characterize the current status of this host-parasite interaction, we established a captive flock of 38 seronegative, healthy finches in fall 1998. after a minimum quarantine period of 4 wk, two mycoplasma gallisepticum (mg)-infected house finches were introduced into this flock. over a 12-wk period, the flock was captured every 2 wk and each bird was obs ...200111332501
gene re-arrangement and fusion in mycoplasma gallisepticum thya-nrdfei locus.sequencing of mycoplasma gallisepticum genome fragment containing thymidylate synthase and ribonucleotide reductase gene clusters reveals both its unusual organization and gene content. sequence analysis indicates the presence of a gene whose product can be considered as a fusion of two full size proteins: the n-terminal part shows significant similarity to mycoplasmal dihydrofolate reductases, while the c-terminal part of the polypeptide chain shows significant similarity to eukaryotic deoxycyt ...200111410345
mycoplasma gallisepticum in house finches (carpodacus mexicanus) and other wild birds associated with poultry production facilities.since 1994, an epidemic of conjunctivitis caused by mycoplasma gallisepticum (mg) has spread throughout the eastern population of house finches (carpodacus mexicanus). the adaptation of mg to a free-flying avian species presents potential problems for the control of mycoplasmosis in commercial poultry. to evaluate risks associated with this emerging problem, a field survey was conducted to assess prevalence of mg infection in house finches and other passerine birds associated with poultry farms. ...200111417811
in vitro susceptibility of avian mycoplasmas to enrofloxacin, sarafloxacin, tylosin, and vitro susceptibility of avian mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) to enrofloxacin, sarafloxacin, tylosin, and oxytetracycline was determined by a serial broth dilution method. the minimum inhibitory concentration (mic) was recognized by a conversion of the ph indicator phenol red in culture media to a yellow color. each isolate or type strain of mycoplasma was tested in two replicates. the mics of tylosin, enrofloxacin, sarafloxacin, and oxytetracycline against five iso ...200111417828
monitoring mycoplasma gallisepticum and mycoplasma synoviae infection in breeder chickens after treatment with enrofloxacin.three experimental strains of breeder chickens were accidentally exposed to mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms), presumably from a newly introduced group of leghorn-type pullets. the experimental strains subsequently became infected and were diagnosed positive for mg and ms by the serum plate agglutination (spa) test and confirmed by the hemagglutination inhibition (hi) test and the polymerase chain reaction (pcr) of tracheal swabs. treatment with 10 mg/kg enrofloxacin via ...200111417841
cases of swollen head syndrome in broiler chickens in greece.from 50 commercial broiler flocks included in a study concerning respiratory disease, signs of swollen head syndrome (shs) were shown in eight. postmortem examination was performed in eight birds showing signs of shs from each flock. the trachea and head from each bird were collected for laboratory investigation. an enzyme-linked immunosorbent assay (elisa) was used for the detection of viral and avian mycoplasma antigens in the trachea, and bacteriologic examinations were performed from the inf ...200111569754
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