control of mycoplasma gallisepticum in commercial laying chickens using artificial exposure to connecticut f strain mycoplasma gallisepticum. 1979298929
an ultrastructural study on the interaction of mycoplasma gallisepticum with the chicken tracheal chickens wee intratracheally inoculated with mycoplasma gallisepticum. the tracheas collected 6 and 14 days after chickens were inoculated were subjected to titration of mycoplasma and examination by light and electron microscopy. the mycoplasma organisms grew well; 10(7) to 10(8) color-changing units in a milligram of tissue were determined. tracheal lesions occurred in close association with the presence of mycoplasmas and were characterized by degeneration of the epithelial cell ...1979507485
the isolation of lentogenic strains of newcastle disease virus in australia.twelve isolations of newcastle disease virus were made from 77 clinical samples from chickens from conjunctivitis, respiratory disease, proventriculitis and bursal atrophy. nine of the isolations were made from chickens with conjunctivitis. the viruses were identified as newcastle disease virus by inhibition of their haemagglutinins with specific antiserum to newcastle disease virus. the viruses failed to kill chicken embryos after inoculation into the allantoic cavity and they were judged to be ...1978687276
further observations on the use of a bivalent bacterin against haemophilus gallinarum.chickens vaccinated with two doses of a bivalent haemophilus gallinarum bacterin were protected against seven strains of the organism. vaccinated and unvaccinated birds with antibody to mycoplasma gallisepticum had increased hi titers when challenged with h. gallinarum. birds positive for antibody to mycoplasma gallisepticum which were not challenged showed no increase in hi titer.1976962761
evaluation of a mycoplasma gallisepticum strain exhibiting reduced virulence for prevention and control of poultry mycoplasmosis.two experiments were conducted to evaluate the virulence and vaccination efficacy of a mycoplasma gallisepticum (mg) isolate designated mg intervet 6/85. virulence of the strain was determined by evaluation of airsacculitis scores following aerosol exposure to the isolate before and after 10 sequential passes in either commercial broiler chickens or commercial turkeys. two-week-old specific-pathogen-free chickens were vaccinated by aerosol exposure. the birds were challenged with the r' strain o ...19921385698
characterization of a major hemagglutinin protein from mycoplasma gallisepticum.mycoplasma gallisepticum cell membranes were used to immunize mice to produce monoclonal antibodies to cell surface proteins. three monoclonal antibodies were chosen for further characterization. all three reacted in immunoblots with an m. gallisepticum protein band of m(r) approximately 67,000 (designated pmga). by using immunoelectron microscopy, pmga was shown to be located on the cell surface. when m. gallisepticum whole cells were treated with up to 250 micrograms of trypsin per ml for 30 m ...19921379991
the effect of including anti-ig sera in the haemagglutination inhibition test for mycoplasma gallisepticum.addition of anti-immunoglobulin m (anti-igm), g (anti-igg) and a (anti-iga) sera to the haemagglutination-inhibition (hi) test (anti-ig hi test) for mycoplasma gallisepticum resulted in 2- to 8-fold increases in the hi titres. on investigating the anti-ig hi reaction using igm and igg antibodies separated by affinity chromatography, it was confirmed that, in the enhanced hi titres, specificity existed between the chicken ig classes having antibody activity and the antisera used in the test. four ...19921413478
successful treatment of mycoplasmosis in layer chickens with single dose therapy.the efficacy of treatment with single dose administration of 5 drugs at different dosages to layer hens naturally infected with mycoplasma gallisepticum was studied. the drugs were tiamulin, which was administered orally, tylosin (parenterally and orally), spiramycin (orally), long-acting oxytetracycline (parenterally) and tylosindihydrostreptomycin (parenterally). cure was assessed by the absence of nasal discharge. the cure rate was significantly higher (p less than 0.05) in treated hens than ...19921379426
demonstration of the genetic stability of a mycoplasma gallisepticum strain following in vivo passage.a mycoplasma gallisepticum strain designated 6/85 (mgi) exhibiting reduced virulence for both chickens and turkeys was sequentially passaged 10 times in each species. dna extracted from organisms before passage and those isolated after the third, sixth, and 10th passages was studied by restriction endonuclease dna analysis using bamhi, bglii, ecori, hindiii, and psti endonucleases. the virulent-type strain designated s6 was used as a comparison. comparison of dna fragment patterns of mgi and s6 ...19921329707
clinical, cultural, and serologic observations of avian mycoplasmosis in two chicken breeder flocks.two chicken breeding flocks from different breeding lines were studied serologically and culturally for mycoplasma gallisepticum (mg) throughout their growing and laying period. infection was proven by successful isolation of mg from both breeders and progeny originating from these two flocks. observations of these flocks which were serologically and culturally negative for mycoplasma synoviae (ms) further disclosed that: 1) negative plate tests of large numbers of day-old progeny may sometimes ...19761259662
a comparison of commercial mycoplasma gallisepticum antigens in the rapid serum agglutination test.twenty-three chickens, aged 9 weeks, were housed in contact with a similar group of chickens which were infected with m. gallisepticum. the onset and development of the serum agglutinin responses which were detected by 3 commercial antigens using rapid serum agglutination tests up to 20 weeks of age, differed greatly both between the infected and in-contact groups and, within the latter group, between the antigens. few reactions, which were weak and transient, were detected in 2 similar groups o ...19751222006
dissociation of mycoplasma gallisepticum membranes with lithium diiodosalicylate and isolation of glycoprotein.m. gallisepticum membranes were treated with 0.3m lithium diiodosalicylate (lis) and, on average, 43% of the original membrane proteins were extracted. the extract contained particles with a sedimentation coefficient of 13s and some aggregated proteins. this lis extract was immunogenic, stimulating the production of haemagglutination-inhibiting, growth-inhibiting and precipitating antibodies in rabbits. it was devoid of haemagglutinating (ha) activity for chicken erythrocytes but did inhibit the ...19751211714
a field trial, using killed-mycoplasma gallisepticum vaccine to protect against chicken respiratory a field trial with chickens, the efficacy of killed mycoplasma gallisepticum vaccine against respiratory mycoplasmosis was determined. broiler chickens were vaccinated by aerosol administration at 3, 14, and 25 days of age, and observations were made of survival rate, body weight gain ratio, macroscopic lesion grade of airsacculitis, isolation of organisms, serologic test results, histopathologic changes, and clinical signs. inhalation of the vaccinal aerosol did not influence livability and ...19751111388
immunization of chickens against mycoplasma gallisepticum infection. 19751092221
attachment of mycoplasma gallisepticum to the tracheal epithelium of electron microscopical study of fowl trachea infected with mycoplasma gallisepticum showed slight to moderate changes at the cellular level. mycoplasmas were demonstrated extra-cellularly and showed triple membranes, intracytoplasmic spaces, fibrillar nuclear areas and blebs. blebs were seen attached to the plasma membrane of the epithelial cells.1977860098
use of the agar-gel precipitin test to evaluate broiler breeder and commercial layer flocks for mycoplasma gallisepticum the absence of mycoplasma gallisepticum (mg) isolation, the importance of agar-gel precipitin (agp) tests along with microhemagglutination-inhibition (mhi) and serum plate agglutination (spa) tests for the evaluation of poultry flocks for mg infection was demonstrated. a good correlation between agp, mhi, and spa tests for the early confirmation of mg in a flock was observed, except for the breeder flocks from which wvu 907 was isolated. the serums of such breeder flocks were positive for spa ...1976822817
effect of tiamulin in chickens and turkeys infected experimentally with avian mycoplasma.tiamulin was compared, under a variety of experimental conditions, with 4 water-soluble antibiotic preparations available commercially for the control and treatment of mycoplasmal infections in poultry. in chickens, tiamulin was more effective than the reference antibiotics in preventing and eradicating airsacculitis caused by mycoplasma gallisepticum and preventing airsacculitis and synovitis caused by m. synoviae. in turkeys, tiamulin and tylosin were equally active in preventing airsacculitis ...1978749887
suppression of immunoresponses to haemophilus gallinarum with nonviable mycoplasma gallisepticum in chickens.the suppressive effect of mycoplasma gallisepticum (mg) on haemophilus gallinarum (hg) immune response was shown. antibody response to hg was highly suppressed when chickens were inoculated intramuscularly with hg-mg combined bacterin. findings were similar in chickens injected intramuscularly with hg and mg bacterin separately at adjacent sites. no immunosuppressive effect was recognized when injections with hg and mg bacterins were in the left and right thigh muscles, respectively, or from int ...1978749885
infectious coryza: preventing complicated coryza with haemophilus gallinarum and mycoplasma gallisepticum bacterins.three types of infectious coryza were produced in unvaccinated chickens by challenge inoculums containing different combinations of haemophilus gallinarum (hg) and mycoplasma gallisepticum (mg). monovalent and combination bacterins of hg and mg were tested to determine their efficacy against chronic complicated infectious coryza. challenge exposure of vaccinates with mg and hg showed protection against the hg component to be immunotype-specific. some protection against complicated coryza resulte ...1978646755
adaptation of chickens to their handler, and experimental results.chickens were adapted to their handler before the experiment. adapted birds produced more antibody, had more blood protein, gained more weight, and were more resistant to mycoplasma gallisepticum than unadapted birds. the antibody response to sheep red blood cells was not reduced for fasting for 48 hours in adapted birds but was in unadapted birds. differences in antibody titers, blood protein, and weight gains between controls and birds fed 80 ppm of deoxycorticosterone could be demonstrated on ...1979526204
an investigation of the persistence of mycoplasma gallisepticum in an eastern population of wild turkeys.mycoplasma gallisepticum infection had been confirmed by culture and serology among wild turkeys (meleagris gallopavo) in close association with domestic fowl on cumberland island, georgia (usa) in 1980. in 1988, wild turkeys were surveyed by serologic and cultural methods for evidence of m. gallisepticum. chickens (gallus gallus) and guinea fowl (numida meleagris) from the site where the disease was originally detected also were tested by serologic and cultural methods for m. gallisepticum infe ...19912023330
examination of mycoplasma gallisepticum isolates from chickens with respiratory disease in a commercial flock vaccinated with a living m. gallisepticum vaccine. 19902076073
haemadsorption inhibition test for the identification of mycoplasma gallisepticum and mycoplasma synoviae.colonies of the avian mycoplasma strains mycoplasma gallisepticum s6 and mycoplasma synoviae wvu 1853 and two mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. three mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. the haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. no cross-inhibition was obser ...1979473153
isolation and identification of avian mycoplasmas in singapore.two hundred and forty batches of chickens with chronic respiratory syndrome were tested for mycoplasmas. one hundred and five batches (43.8%) were found to have mycoplasmosis. a total of 110 isolates of mycoplasma was cultured, of which nine isolates were identified as mycoplasma gallisepticum, 48 avian sero-group d, 45 m. gallinarum, one m. iners and seven unclassified. 2. identification of the mycoplasmas isolated was carried out by biochemical and serological tests (disc growth inhibition and ...1979455110
culturing anomalies associated with mycoplasma recovered from the tissues of chicks and turkey poults experimentally infected with mycoplasma gallisepticum or mycoplasma gallinarum.tissues of mycoplasma infected chicks and turkey poults were cultured and subcultured on mycoplasma agar. usually, colonies which grew on the agar initially inoculated could be subcultured, but sometimes they could not. at other times, colonies were not seen on the agar initially inoculated but appeared on the subcultured plate.1978353927
[studies on the specificity of the hemagglutination inhibition test using mycoplasma gallisepticum and mycoplasma synoviae in experimentally inoculated chickens]. 1977340190
[the "vaccination reaction" syndrome of broilers after vaccination against newcastle disease and infectious bronchitis (author's transl)].in a part of the broiler flocks vaccinated against newcastle disease (n.c.d) and infectious bronchitis (i.b.), disease symptoms of lingering nature have been observed, generally in the second half of the rearing period. in a practical investigation with weekly examinations of chickens, supplemented by a serological examination of twenty-four animals per flock at the age of six weeks, it was hoped to establish the factors responsible for this "vaccination reaction". in the district under notice t ...1976179162
in vivo efficacy of 81.723 hfu, a new pleuromutilin derivative against experimentally induced airsacculitis in chicks and turkey poults.the efficacy of the pleuromutilin derivative 81.723 hfu was tested in chicks and turkey poults by experimentally infecting them with mycoplasma gallisepticum. the data were treated to obtain the mean effective doses, and these were compared to those obtained with tylosin tartrate. the compounds were administered either by ingluvial catheter or via the drinking water. therapy was started on the day of inoculation or 7 days thereafter, respectively. the experiments showed that the compound 81.723 ...19751147586
single and mixed infections of avian infectious bronchitis virus and mycoplasma gallisepticum.comparative studies of the clinical signs, pathological changes, multiplication of the pathogens and serological responses were made of groups of chickens infected with either or both avian infectious bronchitis virus and mycoplasma gallisepticum. electron microscopic examination of thin sections of infected tracheas showed that the multiplication of m. gallisepticum was greatly enhanced in the tracheas of chickens which had been previously or simultaneously infected with avian infectious bronch ...19751126565
factors affecting the development of respiratory disease complex in chickens.factors playing a part in the development of respiratory disease complex in chickens were investigated in a series of experiments. the experimental infection was produced by exposing chickens to mycoplasma gallisepticum and the b1 vaccine strain of newcastle disease virus and later exposing them to aerosols containing the o1:k1 serotype of escherichia coli. chickens became susceptible (pericarditis or death) to e. coli 8 days after mixed respiratory disease challenge. one day after respiratory d ...19902241688
[identification of mycoplasma gallisepticum with a hemadsorption inhibition test]. 1977842193
identification of avian mycoplasma isolates by the agar-gel precipitin test.recent isolates of mycoplasma gallisepticum and mycoplasma synoviae were readily typed by the agar-gel precipitin test with antigens prepared by freezing and thawing, sonic vibration, or sodium dodecyl sulfate. specific antisera prepared in rabbits or in foot-pad-inoculated chickens were adequate for culture typing. relatively few sera from chickens and turkeys in naturally infected flocks reacted positively. the precipitin reaction was highly specific, however.1977410403
localization of an immunodominant 64 kda lipoprotein (lp 64) in the membrane of mycoplasma gallisepticum and its role in cytadherence.a 64 kda lipoprotein (lp 64) haemagglutinin (pi 4.9-5.0) was isolated from the membrane of mycoplasma gallisepticum. triton x-114 phase partitioning has demonstrated that the hydrophobic nature of this haemagglutinin is due to a lipid portion of the molecule. autoradiography of [3h]-palmitate-labelled m. gallisepticum revealed the presence of several additional lipoproteins. immunoelectron microscopy demonstrated the localization of lp 64 to the base of the terminal structure. densitometric scan ...19921406251
effects of ascorbic acid on stress and disease in chickens.white leghorn chickens were given feed containing 100 mg of ascorbic acid (aa)/kg. one day later, treated chickens and a similar group of unmedicated control chickens were chilled for 1 hour at 6 c, exposed to an unusual sound, fasted, or subjected to rough handling. heterophil:lymphocyte (h:l) ratios were determined one day later. the aa-treated birds had significantly lower h:l ratios than untreated controls. chickens that received a diet containing aa had lower h:l ratios than controls (0.86 ...19921417599
sequential intracoelomic and intrabursal immunization of chickens with inactivated mycoplasma gallisepticum bacterin and iota carrageenan adjuvant.chickens immunized by sequential intracoelomic (analogous to intraperitoneal route in mammals) and intrabursal (i.c./i.b.) routes with inactivated mycoplasma gallisepticum (mg) bacterin mixed with 0.2% iota carrageenan (icgn) as an adjuvant were resistant to airsacculitis induced by a subsequent aerosol challenge with virulent r strain mg. in contrast, immunization by the i.c./i.b. routes with inactivated bacterin without the adjuvant or with 0.2% icgn did not confer significant protection. chic ...19921523875
effect of adrenal blocking chemicals on viral and respiratory infections of a series of experiments chickens were treated with chemicals which block the production of corticosterone by the adrenal cortex prior to being challenged with respiratory disease (and other) agents in order to determine if the course of the diseases could be altered. some chickens received a single intramuscular injection (14 mg/kg) of 1,1-dichloro-2,2-bis/p-chlorophenyl/ethane (abc) dissolved in corn oil (20 mg/ml) at least 12 h before challenge. other chickens received feed containing 500 m ...19892536580
combination of immunofluorescence and immunoperoxidase techniques for serotyping mixtures of mycoplasma species.we describe a method for the simultaneous identification of up to three mycoplasma species by the use of contrast-labeled fluorescent antibodies against two species and peroxidase-labeled antibody against a third species. the procedure enabled the rapid identification of colonies of three artificially mixed avian mycoplasma species on agar blocks and also mixtures of species in cultures from naturally infected chickens. furthermore, it was possible to quantitate the components of a mixture of my ...19921537910
sensitivity and specificity of mycoplasma gallisepticum agglutination antigens prepared from medium with artificial liposomes substituting for serum.three batches of strain a5969 mycoplasma gallisepticum (mg) serum-plate-agglutination (spa) antigen grown in regular frey's medium with 12% swine serum, three batches grown in frey's medium containing artificial liposomes instead of serum, and one commercial spa antigen were evaluated for sensitivity and specificity. sensitivity was measured using chickens exposed to mg by intraocular and intranasal inoculation. specificity was measured in uninoculated controls and in groups inoculated with the ...19882461697
nonspecific reactions to mycoplasma serum plate antigens induced by inactivated poultry disease vaccines.nonspecific serum plate agglutination reactions to some avian mycoplasma antigens were induced by injecting chickens with several commercial poultry disease vaccines. all of the vaccines were inactivated, and most of them had oil-emulsion adjuvants. the serum plate agglutination reactions appeared within 2 to 3 weeks post-vaccination and generally persisted for several weeks. the plate test reactions were noted with both mycoplasma gallisepticum (mg) and m. synoviae (ms) antigens, although the d ...19892522768
[tubular structures in mycoplasma gallisepticum and the localization of a tubulin-like protein].in all the strains of m. gallisepticum investigated, a protein with apparent molecular weight 40 kda was revealed by immunoblotting with polyclonal anti-calf brain tubulin antibodies and monoclonal anti-chicken alpha-tubulin antibodies. in other 8 investigated mycoplasma species no positive reactions with the same antibodies were found. the m. gallisepticum cells were examined under electron microscope on fine serial sections and on some sections going at different angles to the long cell axis. ...19921440927
virulence and transmissibility of mycoplasma gallisepticum.the virulence of 4 low passage strains of mycoplasma gallisepticum obtained from different sources within australia was studied by experimental infection of chickens. strain ap3as, originally isolated from the air sac of a broiler chicken, produced severe air sac lesions following injection into the abdominal air sacs of 2-week or 3-week-old chickens, and adult hens. strain 80083 which was isolated from a clinically normal broiler breeder hen was also capable of producing gross air sac lesions f ...19892712773
[molecular biological differences between strains of mycoplasma gallisepticum].differences in virulence of two mycoplasma gallisepticum strains, s6 and a5969, are confirmed in experiments with chickens. macromolecular discrepancies detected between these two strains are concerning the genomic size, electrophoretic spectra of dna and proteins. cross immunoblotting data with polyclonal and monoclonal antibodies reveal major immunogens of protein nature in both the strains. homologous proteins with different electrophoretic mobility are detected in other four m. gallisepticum ...19921455557
mycoplasma gallisepticum vaccination-challenge: an egg-production model.specific-pathogen-free layer hens in maximum lay were exposed by aerosol to a broth culture of mycoplasma gallisepticum r' strain. egg-production loss of greater than 50% was evident 7-14 days following challenge of unvaccinated chickens, with a gradual recovery during the next several days. various vaccine preparations were tested to determine the effect in the model. all vaccinated chickens exhibited significantly (p < or = 0.05) lower egg-production loss than the unvaccinated controls. the mo ...19921485879
immunogenicity of mycoplasma gallisepticum.the serological response and protective immunity elicited in the chicken by the pathogenic ap3as strain and the moderately pathogenic 80083 strain of mycoplasma gallisepticum and variants of strain 80083 attenuated by repeated passage in mycoplasma broth were investigated. strain 80083 elicited a substantial serum antibody response after administration either in drinking water or by conjunctival sac instillation to 7-week-old spf chickens. no vaccinated chickens developed air sac lesions when ch ...19892540737
simultaneous treatment of chickens with salinomycin and tiamulin in feed.laboratory and field experiments involving more than 100,000 birds were performed to assess the effect of simultaneous in-feed medication of chickens with salinomycin and tiamulin at various concentrations. in an artificial infection study with mycoplasma gallisepticum, low levels of tiamulin (10-40 ppm) did not induce signs of ionophore intoxication with salinomycin at 60 ppm in the feed, whereas levels of 50 ppm caused early signs with a mild growth depression. a level of 20 ppm gave a maximum ...19921533113
interference of mycoplasma gallisepticum with multiplication of newcastle disease virus in chickens. 19751164323
an enzyme-linked immunosorbent assay for the detection of specific igg antibody to mycoplasma gallisepticum in sera and tracheobronchial washes.a sensitive indirect elisa is reported for the detection and quantitation of specific igg to mycoplasma gallisepticum (mg) in sera and tracheobronchial washes (tbw) of mg-infected chickens. the sensitivity of the assay was ensured by the use of mouse monoclonal antibody to chicken igg bound to a prospective anti-mg containing sample that was complexed with mg antigen immobilized on a solid phase. the level of specific igg antibody in a test sample was detected by using peroxidase-conjugated goat ...19921569215
pathological and immunological studies on chicken embryos and day-old chicks experimentally infected with mycoplasma gallisepticum. 19862953204
influence of a 12.5 per cent rapeseed diet and an avian reovirus on the production of leg abnormalities in male broiler chickens.the incidence of different forms of leg abnormality were recorded in reovirus (s1133) infected and control male broiler chickens fed on a normal commercial diet or one of similar nutritive value containing 12.5 per cent rapeseed meal. regular serological examination showed that birds remained free from mycoplasma gallisepticum and m synoviae infection throughout the 10 week period of investigation. precipitating antibodies to the reovirus were detected in 90 per cent of the infected birds betwee ...19852983408
an avidin-biotin enhanced dot-immunobinding assay for the detection of mycoplasma gallisepticum and m. synoviae serum antibodies in chickens.a dot-immunobinding assay was enhanced by the incorporation of avidin and biotin reagents into the test system (dab assay). this assay was used to detect serum antibodies to mycoplasma gallisepticum (mg) and m. synoviae (ms) from chickens. serum samples were tested by rapid serum plate (rsp), hemagglutination-inhibition (hi), and dab assay methods. these results were compared. the dab assay was at least 20 times more sensitive in detecting antibodies for ms and at least 75 times more sensitive i ...19902322229
comparison of mycoplasma gallisepticum strains and identification of immunogenic integral membrane proteins with triton x-114 by immunoblotting.pooled chicken antisera from 33 and 77 days post mycoplasma gallisepticum strain r contact-exposure reacted with cell proteins of 19 m. gallisepticum strains. these pooled antisera reacted with more proteins and with greater intensity to reference strains (r, pg31, s6, and a5969) and nine field strains than they did with six other field strains including three (703, 503, and 730) that have been described as serological variants. following extraction with triton x-114 the majority of immunogenic ...19911771754
health survey of backyard poultry and other avian species located within one mile of commercial california meat-turkey flocks.a survey was conducted to characterize domestic and exotic bird populations, estimate seroprevalence to selected disease agents, and describe health management practices on 62 premises containing "backyard" flocks located within one mile of 22 commercial california meat-turkey flocks participating in national animal health monitoring system (nahms). chickens were present on 56 backyard premises and turkeys on seven. antibodies were identified against mycoplasma gallisepticum, m. synoviae, m. mel ...19911854324
comparison of a modified edward-type medium and a modified sp4-type medium for primary isolation of mycoplasma gallisepticum (mg) from chickens vaccinated with the f strain of mg.the efficacy of two media, an edward-type medium (epj) and a modified sp4-type medium (sp4-ps), were compared for primary isolation of mycoplasma gallisepticum (mg) from commercial layer chickens (n = 58) vaccinated with the live f strain of mg. three groups of chickens that differed in the interval after vaccinal exposure to the f strain (32, 41, and 102 weeks) were studied at necropsy. mycoplasma isolation was attempted from the trachea, sinus, and cloaca using lavage and swab techniques but w ...19911953581
cloning and expression in escherichia coli of mycoplasma gallisepticum antigens recognized by sera from infected chickens.a clone bank of mycoplasma gallisepticum (mg) strain a5969 dna was prepared in the expression vector phage lambda gt11. approximately 75% of the resulting phages were recombinants, based upon the insertional inactivation of the lacz gene of the vector. clones were screened immunologically with serum prepared from specific-pathogen-free white leghorn chickens that had been infected with aerosolized mg. approximately 250 clones, or less than 1% of the recombinant phage, reacted positively to vario ...19902142422
identification of species-specific and interspecies-specific polypeptides of mycoplasma gallisepticum and mycoplasma synoviae.temporal antisera (ta) prepared in susceptible leg-horn-type chickens against mycoplasma gallisepticum and m synoviae were evaluated to determine the extent of cross-reactivity in elisa and hemagglutination inhibition tests. species-specific and interspecies-specific polypeptides were identified after electrophoretic separation and protein immunoblotting with reference antisera, ta, and a monoclonal antibody specific for m gallisepticum. mycoplasma gallisepticum antiserum cross-reacted with m sy ...19883377311
safety of temperature sensitive mutant mycoplasma gallisepticum vaccine.a temperature sensitive (ts) vaccine strain designated ts-11 was selected after exposure of a low passage culture of the immunogenic australian field isolate (strain 80083) of mycoplasma gallisepticum to 100 mg/ml of n-methyl-n-nitro-n-nitrosoguanidine. viable counts (assayed as colour changing units (ccu)/25 microliters) of a thawed stock culture of ts-11 were typically log10 3 to log10 5 higher when incubated at 33 degrees c (the permissive temperature) than duplicate viable counts incubated a ...19902143067
immunogenicity of a temperature sensitive mutant mycoplasma gallisepticum vaccine.the immunogenicity of the ts-11 vaccine strain of mycoplasma gallisepticum was assessed following eye drop or coarse aerosol administration in chickens of various ages. protection was evalualted following intra-abdominal (ia) or fine droplet aerosol administration of virulent m. gallisepticum, usually the ap3as strain and was measured mainly by the scoring of gross air sac lesions or by egg production. vaccination of chickens with ts-11 did not elicit a substantial serum antibody response as mea ...19902143068
protection and immunity in commercial chicken layers administered mycoplasma gallisepticum liposomal bacterins.six liposomal mycoplasma gallisepticum (mg) bacterins, differing in charge and size, and two oil-emulsion vaccines (sonicated and non-sonicated) were given to white leghorns in two doses, at 13 weeks and again 1 month later. at 21 weeks of age, all chickens were challenged with a viable 20-hour culture of mg cells (17,800 colony-forming units) intratracheally and with nonviable mg organisms (0.09 mg protein) injected subcutaneously in the wattle center. the three chicken groups that had the lowe ...19873442524
detection of serum antibodies against mycoplasma gallisepticum and mycoplasma synoviae by a dot-immunobinding technique.both mycoplasma gallisepticum (mg) and m. synoviae (ms) antigens prepared for the routine haemagglutination inhibition (hi) test were diluted and absorbed to the separate pieces of durapore membrane for the measurement of dot-immunobinding (dib) titers of test sera. besides, durapore strips bearing both antigens were employed for a dib test with chicken sera definitely diluted 100-fold. shortening of reaction time of chicken sera with antigens as well as with the secondary serum markedly elimina ...19902348588
a quantitative study of single and mixed infection of the chicken trachea by mycoplasma gallisepticum.the interaction between mycoplasma gallisepticum (mg) and the tracheal mucosa of the young chicken was studied. the use of a selective plating method permitted differentiation between a pathogenic tylosin-resistant strain (227) and a less pathogenic tylosin-sensitive vaccine strain (f). both mg strains adhered to the tracheal mucosa and colonized equally well. in mixed infection, the presence or absence of the second strain did not change the efficiency of colonization by either strain. when chi ...19873579778
elimination of mycoplasmal plate agglutination cross-reactions in sera from chickens inoculated with infectious bursal disease viruses.sera from chickens inoculated with various challenge infectious bursal disease viruses or infectious bursal disease vaccines were found to cross-react in the mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) serum plate agglutination (spa) tests. two-fold dilutions of these cross-reacting sera with phosphate-buffered saline before retesting eliminated all non-specific agglutination in the mg and ms spa tests. cross-reactions were observed in the spa test using sera from chickens inocula ...19902173535
efficacy of commercial mycoplasma gallisepticum bacterin (mg-bac) in preventing air-sac lesions in chickens were vaccinated with commercial mycoplasma gallisepticum bacterin subcutaneously and challenged with the s6 strain by the intra-air-sac route 3 weeks later. significantly fewer vaccinated chickens had air-sac lesions than controls.19873579788
a comparison of flow cytometry and other techniques used for diagnosing mycoplasma infections.mycoplasma isolates from chickens are usually identified by a fluorescent antibody (fa) technique that requires 7 to 10 days from sampling to the completion of identification. the fa procedure uses mycoplasma-positive antibodies conjugated with fluoroisothiocyanate (fitc) to identify the colonies of the organism on agar. this paper describes a flow cytometric procedure that uses the same antibody-fitc conjugate and can be completed in 3 or 4 days. broilers and egg-type hens inoculated with mycop ...19902235826
the effect of oxytetracycline on the severity of airsacculitis in chickens infected with mycoplasma gallisepticum.four groups of mycoplasma-free commercial broilers were challenged with the r strain of mycoplasma gallisepticum (mg) at 14 days of age. groups received feed containing either no medication, or 500 ppm or 1000 ppm oxytetracycline (otc) beginning at age 13 days, or 1000 ppm otc beginning at age 15 days. all broilers were vaccinated with a live mild massachusetts infectious bronchitis vaccine at 17 days of age. air sac lesions were scored at age 24 days. in two almost identical experiments, all ot ...19892619666
the isolation and attenuation of a virus causing rhinotracheitis in turkeys in south march 1978, a number of turkeys with severe respiratory symptoms affecting over 80% of the flock were investigated for a possible causative agent. with the standard techniques used for the isolation of bacteriae, mycoplasmae and viruses, only mycoplasma gallisepticum, mycoplasma meleagridis and newcastle disease virus were isolated. tracheal organ cultures were subsequently prepared from 27-day-old turkey embryos and inoculated with sinus exudate from affected turkeys. after an incubation per ...19892748138
an adhesion-hemadsorption inhibition test for the detection of serum antibody to mycoplasma gallisepticum.a simple adhesion-hemadsorption inhibition (ahai) test was developed for the detection of antibodies to mycoplasma gallisepticum in the chicken sera. the ahai antibody was detected simultaneously with hi antibody from sera of chickens intratracheally inoculated with viable cells of m. gallisepticum. a good correlation between hi and ahai antibody titers was obtained with 382 (84.7%) of 451 sera from chickens reared on farms spontaneously contaminated with m. gallisepticum, whereas the remainder, ...19892761140
identification of the antigenic components of the virulent mycoplasma gallisepticum (r) in chickens: their role in differentiation from the vaccine strain (f).the antibody response to different proteins of mycoplasma gallisepticum (mg) was studied in chickens experimentally infected with virulent mg r strain. the chickens were challenged at 8 weeks of age by the intranasal route. each cockerel received 1.3 x 10(6) colony-forming units (cfu). mg strains (r and f) were banded by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). the banding pattern was distinctively different between the two strains in the range of 92.5 to 200 kilodal ...19892773299
preliminary data on efficacy of mycoplasma gallisepticum vaccines containing different adjuvants in laying hens.chickens were vaccinated subcutaneously twice, at 13 and 17 weeks of age. the vaccines used were the whole organisms of mycoplasma gallisepticum (mg) adjuvanted with multilamellar positively charged (mpc) liposomes or oil-emulsion. other chickens received the same bacterins but supplemented with salmonella typhimurium cell wall protein mitogen (stp) (50 micrograms/dose). at 21 weeks of age, each bird was challenged in the right and left caudal thoracic air sacs. the challenge dose/chicken was 1. ...19902260278
role of harderian glands in resistance against mycoplasma gallisepticum challenge.harderian glands of one-day-old chickens were surgically removed. at one week old, these chickens and controls from which these tissues were not removed, were vaccinated intranasally with a temperature-sensitive mutant of mycoplasma gallisepticum. humoral and local immunity were measured by means of antibody in sera and tracheal washings, respectively. protection was measured by resistance to intra-air-sac challenge with the s6 strain of m gallisepticum. there was no discernible difference in ei ...19892595091
evaluation of the specificity and sensitivity of two commercial enzyme-linked immunosorbent assay kits, the serum plate agglutination test, and the hemagglutination-inhibition test for antibodies formed in response to mycoplasma gallisepticum.two commercial enzyme-linked immunosorbent assay (elisa) kits, seven serum plate agglutination (spa) antigens, and the hemagglutination-inhibition (hi) test for antibodies to mycoplasma gallisepticum (mg) were compared for sensitivity and specificity using known mg-positive and mg-negative sera from leghorn chickens. all spa antigens proved to be highly sensitive when testing mg-positive sera. laboratory-prepared spa antigens yielded fewer positive reactions when testing mg-negative sera than co ...19883041957
genetic analysis of immunocompetence measures in a white leghorn chicken line.immunocompetence of the iowa state university s1 white leghorn chicken line was studied. this line was divided into eight sublines based upon erythrocyte antigen b (ea-b) allele (b1b1 or b19b19), antibody response to glutamic acid60-alanine30-tyrosine10 (gat) (high or low), and response to rous sarcoma virus-induced tumors (progression or regression). antibody responses to pasteurella multocida (pm), mycoplasma gallisepticum (mg), and infectious bursal disease virus vaccines were evaluated by en ...19883265514
estimates of quantitative genetic parameters of immunological traits in the chicken.three in vivo assays were used to measure the immunocompetence of chickens in two generations of a selection experiment. the obtained data were used to estimate the variance components for sire and dam for antibody production to pasteurella multocida and mycoplasma gallisepticum vaccines, for t-cell-mediated immunity evaluated by a phytohemagglutinin wing web assay, and for clearance of foreign particles from the circulatory system. heritabilities of and genetic correlations among these immunolo ...19911956847
the humoral immune response of chickens to mycoplasma gallisepticum and mycoplasma synoviae studied by immunoblotting.the humoral immune response over time of white leghorn chickens experimentally infected with mycoplasma gallisepticum or m. synoviae by an aerosol inoculation or a contact exposure were compared by immunoblotting. the response of chickens infected with m. gallisepticum were similar with respect to proteins recognized and intensity of response, regardless of mode of infection. on the other hand, chickens infected by aerosolization of m. synoviae responded to more proteins and with greater intensi ...19902146797
[efficacy of spiramycin and tylosin in preventing mycoplasmosis in chicks experimentally infected with mycoplasma gallisepticum].in order to evaluate the activity of two drugs (spiramycin and tylosin), one-day-old chicks are inoculated with a virulent strain of mycoplasma gallisepticum (mg) and given spiramycin (3 different doses) or tylosin (1 dose) for two or three days. effectiveness is assessed on different criteria: mortality, symptoms, weight gains, gross lesions, mg tracheal recovery and serology. results show that spiramycin and tylosin have the potential of reducing mortality, symptoms and lesions. weight gains o ...19892797880
dna probes for mycoplasma gallisepticum and mycoplasma synoviae: application in experimentally infected chickens.dna probes specific for mycoplasma gallisepticum and m. synoviae were selected from genomic libraries prepared in the puc13 vector. the probes hybridized with the dna of a wide spectrum of strains within each homologous species, but did not react with the heterologous species or with dna from any other avian mycoplasma or bacteria tested. experimental infection and contact exposure of chickens to m. gallisepticum served as models to test the effectiveness of the dna probe in diagnosis as compare ...19892800306
new biotin-conjugated antisera for quantitation of mycoplasma gallisepticum-specific immunoglobulin a in chicken.the biotinylation of goat anti-alpha-chains of chicken immunoglobulin a (iga), suitable for use in an avidin-biotin enzyme-linked immunosorbent assay, is described. the optimum conditions for the use of the developed conjugate in determining local and systemic iga specific to mycoplasma gallisepticum in chickens were established.19883196259
the effect of biological isolation and a molt-inducing regimen on the recovery of mycoplasma gallisepticum from commercial leghorn hens.two trials were conducted to determine the effect of induced molt on the reisolation of mycoplasma gallisepticum (mg) from commercial leghorn hens that had been eyedrop-inoculated with mg at 10 weeks of age. chickens were maintained in a conventional floored chicken house on dry litter through 100 weeks of age. at age 64 weeks, 4 days (trial 1), and at 100 weeks (trial 2), hens were swabbed and cultured for mg and then molted in biological isolation units. swabs were again taken at the end of ea ...19892775101
evaluation of sodium dodecyl sulfate-polyacrylamide gel electrophoresis purified proteins of mycoplasma gallisepticum and m. synoviae as antigens in a dot-enzyme-linked immunosorbent assay.selected immunogenic proteins of mycoplasma gallisepticum (mg) strain r and m. synoviae (ms) isolate f10-2as were purified from sodium dodecyl sulfate-polyacrylamide gels. purified mg proteins of 65 to 63 (p64) kilodaltons (kda), and 26 and 24 (p26/24) kda, and purified ms proteins of 53 (p53) kda, 41 (p41) kda, and 22 (p22) kda were evaluated as potential antigens for an enzyme-linked immunosorbent assay (elisa). chicken antisera to mg, ms, or oil-emulsion vaccines were used to evaluate these p ...19902241683
efficacy of experimental inactivated mycoplasma gallisepticum oil-emulsion bacterin in egg-layer chickens.six groups of white leghorn pullets were studied to determine the ability of beta-propiolactone-inactivated mycoplasma gallisepticum (mg) oil-emulsion bacterins to counteract reductions in egg production caused by mg infection. the pullets were inoculated with 0.5 ml of mg bacterin subcutaneously in the neck at about 20 weeks of age and were challenged with mg near 28 weeks of age, when they were in peak egg production. various challenge schemes with infectious bronchitis virus were used at the ...19852992434
a species-specific dna probe for the detection of mycoplasma 800-base-pair dna fragment from a partial genomic library of mycoplasma gallisepticum was selected and used as a probe for the selective detection of this avian pathogen. the specificity and sensitivity of this probe were demonstrated by using dot blot and southern hybridizations.19873666965
comparison of mycoplasma gallisepticum subunit and whole organism vaccines containing different adjuvants by western immunoblotting.chickens were vaccinated with subunit (adhesin protein) or whole organisms of mycoplasma gallisepticum (mg) adjuvanted with multilamellar positively charged liposomes or oil-emulsion. sera were collected before and following the first (13 weeks of age) and second (17 weeks of age) vaccination. the chicken sera were used in western immunoblotting against whole mg polypeptides. vaccination with the subunit (mg-adhesin) bacterin containing positively charged liposomes resulted in antibody response ...19892683358
detection of antigenic variation among strains of mycoplasma gallisepticum by enzyme-linked immunosorbent inhibition assay (elisia) and western blot analysis.polyclonal antisera (pca) to three mycoplasma gallisepticum (mg) strains (f, s6, and a5969) produced in rabbits were used in enzyme-linked immunosorbent inhibition assay (elisia) and western blot analysis to examine antigenic variability among these strains of mg. in elisia, inhibiting antigen of the same strain used for immunization always led to the greatest percentage inhibition of pca reactivity. western blot analysis of antigens of four mg strains demonstrated both common and restricted pat ...19883060088
effects of dose of antigen and social environment on antibody response of high and low antibody response chickens.chickens selected for high (ha) and low (la) antibody response were exposed to 10-fold doses of red blood cell and killed bacterial antigens while in three different social environments. antibody responses of the ha and la line chickens differed most in the socialized environment and at lower doses of antigen. dose effects were most pronounced in la-line chickens whereas relationship of humans to chickens was most important to ha-line chickens. socialized chickens were more consistent than ignor ...19863737505
influence of f strain mycoplasma gallisepticum infection on response of commercial layers to heat exposure.commercial layers were inoculated with f strain mycoplasma gallisepticum (mg) and housed in either conventional chicken houses or the lower-stress environment of biological isolation units. at the end of 2 weeks, all treatment groups were placed in environmental chambers and subjected to 4 hr of heat stress (40 c with a dew point of 21 c). rectal temperature, an indicator of response to high heat, was monitored. rectal temperatures of f strain mg-inoculated hens housed in the conventional chicke ...19883401170
f strain mycoplasma gallisepticum vaccination of post-production-peak commercial leghorns and its effect on egg and eggshell quality.forty-five-week-old commercial leghorns negative for antibodies to mycoplasma gallisepticum (mg) and m. synoviae were vaccinated with high-passage f strain mg (fmg). hens were confined in modified horsfall-bauer isolation units through 60 weeks of age. egg production (% hen day) and parameters of egg and eggshell quality were monitored, including egg weight, eggshell strength, haugh unit score, pimpling, and blood/meat spot incidence. egg production was significantly lower (p less than 0.05) for ...19883401173
delineation of the lateral spread of mycoplasma gallisepticum infection in chickens.lateral spread of s6 strain mycoplasma gallisepticum (mg) was studied in small populations of chickens. one experimentally exposed bird served as the source of infection, and the presence of mg-agglutinating antibody was evidence of infection in individuals. the results were subjected to survival data analysis. in the seven experiments, four similar but not identical phases of lateral spread were observed: phase 1, a generally long latent phase (median 15, range 12-21 days) before antibody was f ...19873442533
decrease in catalase activity of cultured cells by mycoplasma gallisepticum infection.the effect of mycoplasma gallisepticum infection on the host cell catalase activity was histochemically examined in cultured chicken embryo fibroblasts (cef) and kidney cells. the activity in normal cells was detected as fine, brown granules in the cytoplasm, which appeared ultrastructurally to correspond to anucleoid microbodies. by infecting cultured cells with a cef-passaged strain of m. gallisepticum, the catalase-positive granules clearly decreased in amount, whereas the uv light-killed myc ...19873604054
non-specific agglutination of mycoplasma gallisepticum by rheumatoid factor-like antiglobulin in chickens infected with streptococcus faecalis or staphylococcus aureus. 19734199909
evaluation of respiratory lesions in chickens induced by mycoplasma gallisepticum. 19873626242
pathogenicity of avian reovirus and its influence on the infection of mycoplasma gallisepticum in chickens. 19704318212
spiramycin- and tylosin-resistant strains of mycoplasma gallisepticum isolated from breeding chickens and pipped eggs. 19744444733
development of a biotinylated probe for the rapid detection of mycoplasma gallisepticum.mycoplasma gallisepticum causes respiratory diseases in the form of tracheitis and air sacculitis in chickens and turkeys. it is a major cause of reduced egg production, reduced hatchability, and downgrading of carcasses. current means of diagnosis depend on the isolation and identification of the organisms, or on serological assays to detect serum antibodies. the evaluation of avian sera for m. gallisepticum antibodies is becoming more difficult to interpret, and thus less useful, due to the in ...19873667241
effect of temperature-sensitive mycoplasma gallisepticum vaccine preparations and routes of inoculation on resistance of white leghorns to chickens were vaccinated with live or formalin-killed temperature-sensitive (ts) mycoplasma gallisepticum (mg) either intranasally (in) or subcutaneously (sq). live ts mg protected chickens against s6 strain challenge directly into the air sacs, regardless of route of vaccination. killed mg, however, protected chickens only when administered sq. antibody to mg was detected in sera and in the tracheal and air-sac washings of only the chickens given live vaccine in. the antibody prese ...19863814015
escherichia coli serotypes isolated from chickens infected with mycoplasma gallisepticum. 19724559444
metabolic and growth inhibition of mycoplasma gallisepticum by antiserum. 19734578973
effect of ammonia on mycoplasma gallisepticum infection in chickens. 19734792401
comparison of immunity induced with a mycoplasma gallisepticum bacterin between high- and low-responder lines of chickens.chickens of the high-responder line gsp and low-responder line bm-c, which had been known to have different antibody responses to mycoplasma gallisepticum (mg) antigen, were immunized by intramuscular injection and by subsequent intratracheal instillation of mg bacterin. they were then challenged with the pathogenic strain sas of mg. the preventive effects of local antibodies detectable in the trachea, saliva, and lacrima were compared between the two lines of chickens. the local antibody respon ...19921567299
immunity induced with an aluminum hydroxide-adsorbed mycoplasma gallisepticum bacterin in chickens.the protective effect of an inactivated mycoplasma gallisepticum (mg) bacterin was evaluated in chickens subsequently challenged intratracheally (it) with the homologous strain. antibody responses in sera and tracheal washings (tws) from these chickens were determined by an enzyme-linked immunosorbent assay. a group of chickens was vaccinated intramuscularly (im) with two doses of the bacterin containing aluminum hydroxide gel (im + im). another group was vaccinated im with the same bacterin fol ...19873579785
bacterin to control the vertical transmission of mycoplasma gallisepticum in chickens.a mycoplasma gallisepticum bacterin was prepared and used in mycoplasma gallisepticum (mg)-positive primary breeders to control vertical transmission of mg. two generations were vaccinated, but the third generation was not vaccinated and was monitored serologically. results showed no evidence of mg at 1 day, 6 weeks, 11 weeks, 16 weeks, or 31 weeks of age. this procedure may offer small breeder organizations and showbird fanciers a way to eliminate mg.19853833226
evaluation of protection against colonization of the chicken trachea following administration of mycoplasma gallisepticum bacterin.twelve-week-old commercial white leghorn pullets were given one or two doses of an inactivated oil-emulsion mycoplasma gallisepticum (mg) vaccine or kept as unvaccinated controls. at 24 weeks of age, all groups were challenged intratracheally with one of six dilutions of a low-passage r strain of mg. three days postchallenge, the tracheas from all chickens were cultured for mg to determine the number of challenge organisms required to initiate infection. the log10 id50 of chickens vaccinated 0, ...19853833239
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