Publications

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the need for standardisation of serological techniques for the detection of mycoplasma gallisepticum infection in poultry. 19666008170
the action of mycoplasma gallisepticum upon chicken, rabbit, and cow erythrocytes. 19676069464
effect of dipping eggs in spiramycin to inactivate mycoplasma gallisepticum. 19666007461
[on the induction of antibiotic resistance in "mycoplasma gallisepticum"]. 19665999417
the incidence of mycoplasma gallisepticum, salmonella pullorum, salmonella typhimurium, and newcastle disease virus antibodies in certain wisconsin chickens. 19666008331
mycoplasma gallisepticum infection in germfree and conventional chickens: experimental studies with a culture of low virulence. 19676033700
a culture medium for the production of mycoplasma gallisepticum antigen. 19676029588
use of formalinized mycoplasma gallisepticum antigens and chicken erythrocytes in hemagglutination and hemagglutination-inhibition studies.antigens were prepared from mycoplasma gallisepticum in the logarithmic phase of growth and were treated with 2, 5, and 10% formalin by slow diffusion through a dialysis sac. chicken erythrocytes were similarly treated with 20% formalin. formalin-treated antigens hemagglutinated fresh and formalinized chicken erythrocytes. the antigens retained this hemagglutinating ability over an extended period.19676029826
volume regulation in mycoplasma gallisepticum.cells of mycoplasma gallisepticum incubated in 250 mm nacl in the absence of glucose for several hours show swelling and eventual lysis. this swelling is believed to be due to colloid osmotic and donnan forces, since it is prevented by the addition of nondiffusable solutes such as sucrose or mgso4. the addition of glucose during the swelling stage (but before lysis) caused shrinkage and return to initial volume. experiments on na+ and h+ movement are consistent with the operation of an atp-drive ...19846096306
transmission of mycoplasma gallisepticum in turkeys. 19676073842
pathology in chickens experimentally inoculated or contact-infected with mycoplasma gallisepticum. 19676073844
serological responses of chickens naturally infected with mycoplasma gallisepticum and the effect of tylosin on these responses. 19676078266
use of egg yolk in serological tests (elisa and hi) to detect antibody to newcastle disease, infectious bronchitis, and mycoplasma gallisepticum.serum and yolks from commercial flocks and from hens exposed to newcastle disease virus (ndv), infectious bronchitis virus (ibv), and mycoplasma gallisepticum (mg) were tested for immunoglobulin g antibody by the enzyme-linked immunosorbent assay (elisa) and the hemagglutination-inhibition (hi) test. yolks prepared by chloroform extraction and low-speed centrifugation performed well in the serological tests used and were a suitable alternative to serum for antibody determination by the elisa for ...19846098252
mode of action of the copper(i) complex of 2,9-dimethyl-1,10-phenanthroline on mycoplasma gallisepticum.various physiological important activities of mycoplasma gallisepticum were inhibited by the copper(i) complex of 2,9-dimethyl-1,10-phenanthroline [cu(dmp)2no3]. the energy-yielding metabolism was inhibited because the conversion of pyruvate into lactate was found to be blocked by cu(dmp)2no3, indicating a selective inhibition of lactate dehydrogenase. also, the production rate of acetate and the rate of oxygen uptake by whole cells of m. gallisepticum appeared to be strongly decreased. experime ...19816177282
capsular material of mycoplasma gallisepticum and its possible relevance to the pathogenic process.a ruthenium red-staining capsule was observed on two pathogenic strains, but not on one nonpathogenic strain of mycoplasma gallisepticum. the capsule appeared to mediate cytadsorption of mycoplasmas to the chicken tracheal epithelium without evidence of membrane fusion. no relationship was seen between the presence of capsule and hemagglutination titers of the strains examined.19826177640
egg production in relation to the results of a long term serological survey of 73 flocks of fowl.seventy-three flocks of fowl were tested at regular intervals for the presence of precipitins to fowl adenovirus (av) and infectious bronchitis virus (ibv), haemaggluinating inhibiting antibodies to bc in 14 virus, and of agglutinins to mycoplasma gallisepticum (m.g.) and mycoplasma synoviae (m.s.). in all the eight flocks affected with egg drop syndrome (eds '76), egg production problems were associated with increasing numbers of bc14 virus reactors and av reactors. in flocks showing production ...19806243424
effect of mycoplasma gallisepticum on genetically defined chickens.three parameters were used to measure differences between arkansas progressor and regressor lines of chickens in response to mycoplasma gallisepticum inoculations. the responses of regressor and progressor lines to m. gallisepticum did not differ as judged by antibody response, severity of airsacculitis, and resistance of tracheal ring tissue cultures from 20-day-old progressor and regressor chick embryos to m. gallisepticum.19826284109
observations on the pathogenicity of alcaligenes faecalis in chickens.a series of trials was conducted in which specific-pathogen-free (spf) leghorn chicks were exposed to various isolates of alcaligenes faecalis. chicks were inoculated with a. faecalis alone or in combination with newcastle disease/infectious bronchitis (nc/br) vaccine, laryngotracheitis vaccine, infectious bursal disease virus, or mycoplasma gallisepticum. the response was evaluated by morbidity, mortality, airsacculitis, reisolation of a. faecalis, and histopathological lesions of tracheas. alt ...19836227315
interaction of mycoplasma gallisepticum with sialyl glycoproteins.the binding of several glycoproteins to freshly grown and harvested cells of mycoplasma gallisepticum was examined. only human glycophorin, the major sialoglycoprotein of the erythrocyte membrane, bound tightly as judged by direct binding assays with 125i-labeled glycoproteins. neuraminidase-treated glycophorin did not bind, suggesting that binding is mediated through sialic acid groups. although other sialoglycoproteins did not appear to bind m. gallisepticum by direct binding assays, some inhi ...19806160107
immunization of chickens with temperature-sensitive mutants of mycoplasma gallisepticum.temperature-sensitive (ts) mutants of the s6 strain of mycoplasma gallisepticum (mg) were used to immunize newly hatched chickens. immunized chickens developed antibodies to the wild-type (wt) s6 strain as demonstrated by serologic tests. mg was recovered from nasal cavities but not from the lower respiratory tract of the immunized chicks. three weeks after intranasal immunization, chickens were challenged via the air sacs with the virulent s6 strain. immunized chickens were significantly better ...19836227317
pathogenicity of two strains of mycoplasma gallisepticum in broilers.strains f and r of mycoplasma gallisepticum (mg) were compared in two laboratory trials for their relative pathogenicity in terms of inducing airsacculitis and antibody production to mg. chickens exposed to the r strain had significantly higher incidence of air-sac lesions (p less than 0.05) and greater severity of airsacculitis than did chicks exposed to the f strain. in both trials, chickens vaccinated simultaneously with newcastle disease-infectious bronchitis vaccine and exposed to mg had mo ...19806268040
performance of 3 successive generations of specified-pathogenfree chickens maintained as a closed flock.no antibodies against salmonella pullorum, mycoplasma gallisepticum, mycoplasma synoviae, haemophilus gallinarum, fowl pox virus, marek's disease virus, herpes virus of turkey, infectious laryngotracheitis virus, avian adenovirus, avian reovirus, infectious bursal disease virus, reticuloendotheliosis virus, avian leukosis virus, avian encephalomyelitis virus and newcastle disease virus were detectable in the sera obtained from these chickens in 3 generations at various ages. antibodies against i ...19806253742
influence of mycoplasma gallisepticum, infectious bronchitis, and cyclophosphamide on chickens protected by native intestinal microflora against salmonella typhimurium or escherichia coli.chickens that have considerable resistance to salmonella typhimurium or escherichia coli infection by early development of a native intestinal microflora shed these bacteria following aerosol exposure to mycoplasma gallisepticum and/or infectious bronchitis virus. administration of cyclophosphamide to similarly treated chickens induced slight shedding of these bacteria, and the combination of cyclophosphamide and respiratory agents magnified the shedding rate. these agents also influenced the is ...19846331365
further studies on the immunization of chickens with temperature-sensitive mycoplasma gallisepticum mutant.newly hatched chickens were immunized with a temperature-sensitive (ts) mycoplasma gallisepticum (mg) mutant (ts 100). immunized chickens resisted challenge with the virulent s6 strain. the dose of ts mg needed for protection was less than 3.3 x 10(4) colony-forming units. after immunization with ts 100, chickens were subjected to a variety of virus infection and immunosuppressive treatments. neonatal bursectomy or thymectomy, infectious bursal disease virus infection, and infectious bronchitis ...19846326734
avian mycoplasma infections: prototype of mixed infections with mycoplasmas, bacteria and viruses.mixed infections involving mycoplasmas, viruses and bacteria are well recognized in chickens. synergism has been demonstrated between mycoplasma gallisepticum and the viruses of newcastle disease and infectious bronchitis and escherichia coli, although the outcome of infection is influenced by many factors associated with the host and the organisms. airsacculitis in broilers due to m. synoviae or m. gallinarum may be precipitated by concurrent respiratory virus infections including vaccine strai ...19846324630
[usefulness of the agar precipitation test for the determination of the antigenic properties of mycoplasma gallisepticum. i. double diffusion test in agar gel].the usefulness of the double diffusion test in agar gel for the analysis of sero-antigenic structure of mycoplasms was exemplified with serotype s6 mycoplasma gallispeticum. serum of a high precipitation value obtained on rabbits intradermally vaccinated with a suspension of mycoplasms with a complete freund's adjuvant was used. as antigens in the reactions with a specific antiserum was applied an ultrasonic disintegrate of the same suspension of mycoplasms, and in order to elucidate an eventual ...19836415620
the effect of oil-emulsion vaccines on the occurrence of nonspecific plate agglutination reactions for mycoplasma gallisepticum and m. synoviae.six groups of ten 18-week-old mycoplasma-free white leghorn pullets were vaccinated with one of the following: mycoplasma gallisepticum (mg) bacterin. haemophilus gallinarum bacterin, pasteurella multocida bacterin, combined infectious bursal disease (ibd)-newcastle (ndv) chicken-embryo-origin (ceo) vaccine. ibd-ndv tissue-culture-origin (tc) vaccine, or saline emulsified in oil; one group received no vaccine. plate agglutination tests for m. synoviae (ms) and mg were done for 10 weeks after vac ...19846331364
application of enzyme-linked immunosorbent assay for detecting antibody to mycoplasma gallisepticum infections in poultry.an enzyme-linked immunosorbent assay (myco-elisa) was developed to detect antibodies to mycoplasma gallisepticum (mg) in chicken sera. the assay was standardized in terms of optimum antigen concentration, serum dilution, conjugate dilution and incubation temperature, and time. the myco-elisa antigen was prepared from mg whole bacterial cell or its disrupted cell suspension. both preparations showed strong affinity for binding or adsorbing to the surface of polystyrene wells of the microtiter pla ...19836342593
dna cleavage patterns as indicators of genotypic heterogeneity among strains of acholeplasma and mycoplasma species.electrophoretic patterns of digestion products of acholeplasma and mycoplasma dna by restriction endonucleases were compared. the patterns of acholeplasma axanthum strains isolated from a variety of hosts and habitats differed markedly from each other, indicating considerable genotypic heterogeneity among strains included in this species. heterogeneity was less marked among the acholeplasma oculi strains tested, and was minimal among strains of the avian pathogen mycoplasma gallisepticum. strain ...19836313853
demonstration of mycoplasma gallisepticum in tracheas of healthy carrier chickens by fluorescent-antibody procedure and the significance of certain serologic tests in estimating antibody response.chickens naturally infected with mycoplasma gallisepticum (mg) were cultured by tracheal swab. although the chickens showed no signs of disease, they remained mg carriers many months after the acute phase of infection. when mg was isolated from tracheas, the agent was demonstrated also in smear preparations from tracheal mucus by the indirect fluorescent-antibody procedure. humoral immune response to mg was low, as detected by rapid serum-plate-agglutination, micro-tube-agglutination, hemaggluti ...19846435592
the adhesins of mycoplasma gallisepticum and m. pneumoniae.the growth of m. gallisepticum was monitored in regard to their capacity to haemagglutinate. the maximal potential was with cells grown for about 22 h. m. gallisepticum, like m. pneumoniae, possess a triton shell intracellular filamentous structure which is revealed by exposing the cells to a relatively low concentration of triton-x100. the adhesin of m. gallisepticum was partially purified on sialoglycopeptide conjugated to sepharose-4b. the adhesin fraction was primarily composed of one polype ...19846424524
absence of mycoplasma pneumoniae cytadsorption protein p1 in mycoplasma genitalium and mycoplasma gallisepticum.polyclonal and monoclonal antibodies to mycoplasma pneumoniae protein p1 were nonreactive with whole-cell or soluble preparations of m. genitalium and m. gallisepticum. however, radioimmunoprecipitation performed with hyperimmune rabbit sera raised against each mycoplasma species indicated antigenic cross-reactivity between m. pneumoniae and m. genitalium.19846421736
a comparison of the methods of the european pharmacopoeia for the detection of mycoplasma gallisepticum and mycoplasma synoviae.the methods specified in the european pharmacopoeia for the detection of mycoplasma synoviae and mycoplasma gallisepticum as contaminants of vaccines were compared by investigating the serological responses of chicks inoculated with dilutions of mycoplasma cultures, these cultures being titrated in parallel in vitro. inoculation by the intrathoracic route proved to be as sensitive as, or more sensitive than the other methods and was of similar sensitivity to the in vitro titrations for both agen ...19846480614
decreases in rates of lipid exchange between mycoplasma gallisepticum cells and unilamellar vesicles by incorporation of sphingomyelin.the kinetics of exchange of radiolabeled cholesterol and phospholipids between mycoplasma gallisepticum cells and an excess of small unilamellar phospholipid/cholesterol vesicles were studied using cells enriched with different phospholipid classes but the same fatty acyl content. the rates of the rapidly exchanging cholesterol and phospholipid pools were markedly slower in sphingomyelin-containing cells than in phosphatidylcholine-containing cells. the decreased rates of spontaneous cholesterol ...19846469983
improving the mycoplasma gallisepticum and m. synoviae antigen yield by readjusting the ph of the growth medium to the original alkaline state.the ph of mycoplasma gallisepticum (mg) and m. synoviae (ms) growth medium was readjusted back to the original alkaline state when the ph reached 6.1 (for mg) and 6.7 (for ms), and the medium was reincubated until the ph of the medium returned to 6.7 to 6.9. the result was that mg and ms antigen yields were 43 and 54% higher than yields obtained at the usual harvest time.19846372778
effect of trichothecenes on growth and intracellular pool size of mycoplasma gallisepticum.the mycotoxin t-2 inhibited the growth of mycoplasma gallisepticum. the growth inhibition was most pronounced with the hydrophobic derivatives t-2 acetate and very little with the hydrophilic t-2 tetraol. the toxin had no effect on the biosynthesis of either protein, dna, rna or complex lipids but markedly reduced the intracellular pool size of soluble low molecular mass precursors. it seems that t-2 acetate, by virtue of its hydrophobic nature, may accumulate within the lipid backbone affecting ...19846479334
two cholesterol pools in acholeplasma laidlawii membranes.cholesterol exchange kinetics between [14c]cholesterol-labeled acholeplasma laidlawii and mycoplasma gallisepticum cells and phosphatidylcholine-cholesterol vesicles followed a biphasic curve, with faster exchange rates for a. laidlawii. the same biphasic curve was obtained with isolated membranes. cholesterol exchange between lipid vesicles and a. laidlawii cells depleted of phospholipids by phospholipase a2, fitted a monophasic linear curve. the data support the hypothesis that the biphasic ch ...19846479337
an epornitic of mycoplasma gallisepticum in turkeys.a major epornitic of mycoplasma gallisepticum occurred in the monroe, north carolina, area between january and june of 1983. the outbreak involved 304,000 turkeys of various ages, which were slaughtered in the eradication program at a cost of more than $550,000 to growers and poultry companies. an infected peafowl was the likely source of infection on the first farm. traffic between farms by growers and company personnel was theorized to be the means of further spread.19846487195
infectious sinusitis in turkeys at ibadan, nigeria.thirty out of 70 imported broad-breasted white turkeys with severe sinusitis were both culturally and serologically positive for mycoplasma gallisepticum. infectious sinusitis due to m. gallisepticum was therefore diagnosed. a low mortality of 5.7% of the total flock was recorded. this appears to be the first published report on m. gallisepticum isolation in turkeys in nigeria.19846487193
resistance of chickens immunized against mycoplasma gallisepticum is mediated by bursal dependent lymphoid cells.newly hatched chickens were significantly protected against challenge by the virulent s6 strain of mycoplasma gallisepticum after vaccination with the ts 100 mutant. removal of the thymus did not abolish the protective effect of the vaccine, but removal of the bursa of fabricius did. the results suggest that the resistance induced by vaccine is mediated by the bursal-dependent lymphoid cells.19846495612
early stages in the interaction between mycoplasma gallisepticum and the chick trachea, as related to pathogenicity and immunogenicity.mycoplasma strains, which occur naturally or as the result of laboratory manipulation, differ markedly in biological properties such as pathogenicity, infectivity, transmissibility, and immunogenicity. these properties are clinical expressions of a series of complex interactions between the mycoplasma organisms and the host. we have focused on the early interactions occurring at the level of the tracheal mucosa, with the intent of identifying mycoplasma gallisepticum strains possessing a combina ...19846511325
uptake and transbilayer distribution of phosphatidylcholines in mycoplasma gallisepticum and their effect on cell morphology.mycoplasma gallisepticum cells grown in a serum-free medium incorporated large amounts of egg-phosphatidylcholine (egg-pc), dioleoylphosphatidylcholine (dopc) or dipalmitoylphosphatidylcholine (dppc) added to the growth medium. egg-pc and dopc were incorporated at a high rate and to a large extent and were modified by the organisms, whereas dppc was incorporated at a lower rate and to a lesser extent and was not modified by the cells. the lactoperoxidase-mediated radioiodination applied to study ...19846511357
a urease-elisa for the detection of mycoplasma infections in poultry.an elisa utilising a urease-antibody conjugate specific to chicken igg was examined as an alternative to the serum agglutination and the haemagglutination inhibition tests in the diagnosis of mycoplasma gallisepticum and m. synoviae infections in poultry. use of a urease conjugate allowed the serum reactions to be appraised without the need for expensive photometric equipment. non-specific binding of conjugate to antigen was eliminated by treatment of antigen coated microplates with 10% foetal c ...19846378168
utilization of temperature-sensitive mutants of mycoplasma gallisepticum to prevent air sac infections.three stable temperature-sensitive (ts) mutants were obtained by treating the s6 strain of mycoplasma gallisepticum with 50 micrograms/ml of nitrosoguanidine. these mutants were morphologically and serologically indistinguishable from the parent s6 strain. mutants ts 37 and ts 102 were apathogenic, and ts 100 was moderately pathogenic to chickens when inoculated directly into the air sac. to turkeys, ts 37 remained apathogenic, ts 102 was slightly pathogenic, and ts 100 was highly pathogenic, in ...19846511327
mycoplasma gallisepticum isolation in layers.mycoplasma gallisepticum (mg) isolations in live chickens have been made from swabs obtained primarily from the trachea or nasal exudates. as tracheal swabs are often contaminated with feed and because tracheal swabbing may be stressful to the bird, this study was conducted to determine if swabs from the choanal cleft (palatine fissure) would yield mg isolation rates comparable to mg isolation rates of swabs taken from the trachea. commercial leghorns from 17 to 22 weeks of age were inoculated v ...19846387691
vaccination of turkeys against air-sac infection with a temperature-sensitive mutant of mycoplasma gallisepticum.turkeys were vaccinated with temperature-sensitive (ts) mutants of mycoplasma gallisepticum (mg) to determine pathogenicity and immunogenicity. ts 37 was apathogenic yet immunogenic to turkeys, ts 100 was highly pathogenic, and ts 102 was slightly pathogenic and nonimmunogenic. five or 7 weeks after intranasal vaccination of turkeys with the ts 37 mutant, a highly statistically significant resistance against intra-air-sac challenge with the s6 strain of mg was observed.19846525130
indirect micro-enzyme-linked immunosorbent assay for the detection of antibodies to mycoplasma synoviae and m. gallisepticum.the sensitivity and specificity of the indirect micro-enzyme-linked immunosorbent assay (elisa) was compared with that of the rapid serum-plate test (rspt) and the hemagglutination-inhibition test (hit) in detecting antibodies to mycoplasma gallisepticum (mg) and m. synoviae (ms). membrane antigens of mg strain s6 and ms strain nel 61800 were used. elisa was performed with single ms and single mg antigens and a combined ms/mg antigen. the ms-elisa was as sensitive as the ms-rspt and more sensiti ...19836639552
temperature-sensitive mutants of mycoplasma gallisepticum.mycoplasma gallisepticum (mg) s6 strain was treated with nitrosoguanidine to obtain temperature-sensitive mutants. of the 101 colonies screened, 4 were found to be temperature sensitive. these mutants and the wild type organisms were serologically and morphologically identical. three of the 4 mutants failed to produce air sac lesions when inoculated directly into air sacs of the chicken.19846699219
mycoplasma gallisepticum infection in wild-type turkeys living in close contact with domestic fowl.mycoplasma gallisepticum was isolated from 2 wild-type turkeys (meleagris gallopavo) and 1 domestic turkey living in close contact on a farm in tehama county, california. sinusitis was detected in 2 of 14 wild-type turkeys and in 1 of 12 feral broad-breasted bronze turkeys, but in none of several chickens on the premises. the entire mixed flock was captured, sinus aspirates were collected from affected birds, and blood samples were obtained from all birds for serologic testing. blood samples als ...19836643238
bacterins and vaccines for the control of mycoplasma gallisepticum.the preferred method for the control of mycoplasma gallisepticum is eradication. unfortunately, the advent of multiple-age farms for poultry production has made eradication impractical after the organism has been introduced. live vaccination with the f strain of m. gallisepticum during the rearing period has been used to prevent egg production losses. more recently, an inactivated oil emulsion bacterin has become available commercially. vaccine and bacterin offer protection against egg productio ...19846548986
mycoplasma gallisepticum in culture with biosilon microcarrier beads.various dilutions of mycoplasma gallisepticum were cultured in the presence of biosilon microcarrier beads. the microcarriers did not affect the recoverability or the growth rate of m. gallisepticum. cultures attained a higher density in the presence of microcarriers. the initiation of a culture could be accomplished by the transfer of one bead from a microcarrier culture.19836630451
forms of leg abnormality observed in male broilers fed on a diet containing 12.5 percent rapeseed meal.the incidence of leg abnormalities was studied in 216 male ross i broilers, fed for 10 weeks on a diet containing 12.5 per cent extracted rapeseed. regular serological examination showed that the birds remained free from mycoplasma gallisepticum, mycoplasma synoviae and avian reovirus throughout the period of investigation. post mortem examination and radiographs were performed when birds were culled due to leg deformities or at the end of the experiment. leg abnormalities were seen in 19.4 per ...19836635344
evaluation of the microagglutination test in the diagnosis of mycoplasma gallisepticum infection in chickens.the sensitivity and specificity of the microagglutination (ma), serum-plate-agglutination (sp), and hemagglutination-inhibition (hi) test for mycoplasma gallisepticum (mg) were compared in groups of chickens infected with mg, m. synoviae, or pasteurella multocida or inoculated with bacterins prepared from staphylococcus aureus or erysipelothrix rhusiopathiae. of the three tests evaluated, the hi test had the highest specificity, but it was the least sensitive. both the ma and sp tests were more ...19846721803
transferred humoral immunity in chickens to mycoplasma gallisepticum.progeny chicks of mycoplasma gallisepticum (mg)-infected and mg-free white leghorns were used to evaluate the protective effects of maternal antibodies against aerosol challenge with the virulent r strain of mg at 3, 7, or 14 days of age. interference by maternal antibodies with day-1 vaccination with the f strain of mg was also studied. in another trial, 8, 4, or 2 ml of high- or low-titered antiserum was given to 20-day-old commercial white leghorn chicks. protection was measured in terms of a ...19846721806
evaluation of attenuated strains of mycoplasma gallisepticum as vaccines in young chickens.five trials were conducted to evaluate the virulence and the vaccination efficacy of the f, r, s6, and a5969 strains of mycoplasma gallisepticum (mg) at different in vitro passage levels. vaccination was done by eye-drop or aerosol, and efficacy was evaluated in terms of air-sac lesions after aerosol challenge with the r strain of mg. continuing medium passage of these strains of mg resulted in gradual attenuation. aerosol vaccination with highly attenuated mg at 21 days of age was more effectiv ...19846721807
synthesis of adenylate nucleotides by mollicutes (mycoplasmas).cultures of the mollicutes (mycoplasma) acholeplasma laidlawii b, acholeplasma morum, mycoplasma bovis, mycoplasma arginini, mycoplasma fermentans and mycoplasma gallisepticum, representing four metabolic groups, were sampled at intervals over a 40 to 50 h period and assayed for the numbers of c.f.u., changes in ph and glucose concentration, and concentrations of atp, adp, amp, lactate and pyruvate. the adenylate energy charge (eca), the mean generation time, and the number of nmol of atp (mg dr ...19836655457
evaluation of inactivated mycoplasma gallisepticum oil-emulsion bacterins for protection against airsacculitis in broilers.broiler chicks were vaccinated subcutaneously in the neck at various ages with a single 0.5-ml dose of beta-propiolactone-inactivated mycoplasma gallisepticum (mg) oil-emulsion bacterin. four weeks later, vaccinated and control chicks were placed in cold environmental cabinets, infected with infectious bronchitis virus intratracheally, and 2 days later challenged by aerosol exposure to live mg broth culture. all chicks were killed 21 days later and scored postmortem for the rate and severity of ...19846721795
correlation of titer, preservation method, and storage of mycoplasma gallisepticum f strain and the immune response in chickens.the f strain of mycoplasma gallisepticum (mg) was used either fresh or after lyophilization or freezing at -60 c to vaccinate young leghorn chickens. vaccine stored either frozen or lyophilized for 22 months was also used. each vaccine preparation was given at dosages ranging from 10(5) to 10(9) colony-forming units/ml. all dosage levels of mg significantly (p less than 0.05) reduced air-sac lesion scores after aerosol challenge with the r strain of mg at 6 weeks postvaccination, regardless of t ...19846721801
mycoplasma gallisepticum vaccination: effects on egg transmission and egg production.the effects of mycoplasma gallisepticum (mg) vaccination on egg transmission of mg and egg production were evaluated. leghorn hens vaccinated with live mg (strain f), with strain f plus mg bacterin, with one dose of mg bacterin, or with two doses of mg bacterin all transmitted mg through the egg at a significantly lower level than unvaccinated controls. hens vaccinated with two doses of mg bacterin had the longest lag before detectable transmission of mg through the egg. all vaccinated groups we ...19846743175
mycoplasma challenge studies in budgerigars (melopsittacus undulatus) and chickens.an upper respiratory condition that resulted in 20% mortality in a flock of yellow-naped amazon parrots was apparently caused by a concomitant infection of mycoplasmas and bacteria. mycoplasma gallisepticum (mg), m. iowae, and an unidentified mycoplasma were isolated from the affected parrots. budgerigars were experimentally infected with a parrot strain of mg designated mg(p) 1669 as well as with the r strain of mg and the f10-2 strain of m. synoviae (ms). air-sac lesions were evident in all gr ...19846743176
a novel method for the determination of electrical potentials across cellular membranes. ii. membrane potentials of acholeplasmas, mycoplasmas, streptococci and erythrocytes.the membrane potentials of acholeplasma laidlawii, mycoplasma mycoides subsp. capri, mycoplasma gallisepticum, streptococcus faecalis and human erythrocytes have been determined by applying a novel technique. the membrane potentials were calculated simply from potassium concentrations determined by atomic absorption spectroscopy, and gravimetry. the versatility of the new technique is demonstrated by comparing our results with data obtained by different techniques.19806773575
scanning electron microscopy of mycoplasmas adhering to erythrocytes.the interaction of mycoplasma pneumoniae and mycoplasma gallisepticum with human erythrocytes (rbc) was studied by scanning electron microscopy. the tight nature of the attachment of the microorganisms to the rbc was indicated by the indentation of the rbc surface at the site of attachment of m. gallisepticum cells and by traction and resulting distortion in the shape of the rbc at the point of its attachment to m. pneumoniae filaments growing on glass or plastic. in many cases attachment took p ...19806777306
mycoplasma gallisepticum (mg)--laboratory and field studies evaluating the safety and efficacy of an inactivated mg bacterin.a highly antigenic isolate of mycoplasma gallisepticum (mg) was utilized in the production of an inactivated, oil-emulsified mg bacterin (mgb). laboratory tests indicated that the bacterin was capable of protecting chickens from clinical signs of mg caused by intrasinus challenge with the r, s-6, pg-31, or 1150 strain of mg. vaccinated turkeys also were protected from clinical signs of disease when challenged with mg. use of the mgb in chickens under laboratory conditions resulted in a reduction ...19836688951
kinetics of cholesterol and phospholipid exchange between mycoplasma gallisepticum cells and lipid vesicles. alterations in membrane cholesterol and protein content.the kinetics of exchange of radiolabeled cholesterol and phospholipids between intact mycoplasma gallisepticum cells and unilamellar lipid vesicles were investigated over a wide range of cholesterol/phospholipid molar ratio. the change in cholesterol/phospholipid molar ratio was achieved by adapting the sterol-requiring m. gallisepticum to grow in cholesterol-poor media, providing cells with decreased unesterified cholesterol content. at least 90% of the cholesterol molecules in unsealed m. gall ...19846706945
distribution and movement of sterols with different side chain structures between the two leaflets of the membrane bilayer of mycoplasma cells.mycoplasma gallisepticum was adapted to grow with delta 5-sterols modified in the aliphatic side chain, and stopped-flow kinetic measurements of filipin association were made to estimate the sterol distribution between the two leaflets of the membrane. cholesterol derivatives with unsaturated side chains (desmosterol, cis- and trans-22-dehydrocholesterol, and cholesta-5,22e,24-trien-3 beta-ol) or an alkyl substituent (beta-sitosterol) were predominantly (86-94%) localized in the outer leaflet of ...19846706946
inactivation of mycoplasmas by long-chain alcohols.in this report, we describe the inhibitory activity of long-chain alcohols on the growth of mycoplasma gallisepticum and mycoplasma pneumoniae. peak inhibition was recorded with saturated primary alcohols (64 microm) varying in chain length from 16 to 19 carbon atoms. the unsaturated alcohols (oleyl, linoleyl, and linolenyl) and the secondary alcohol (pentadecan-2-ol), when employed in the same test conditions, were considerably less effective growth inhibitors than the primary saturated alcohol ...19816794448
detection of mixed mycoplasma species.immunofluorescence can be used to demonstrate mixed species within a mycoplasma culture; however, it may fail to do so if one species is present in very low numbers. to enhance the detection of minor components in such mixtures, a technique was developed, based on the growth inhibition test, whereby the growth of the major component in a mixed culture was inhibited, thus permitting the minor component to emerge. the method was applied to 67 field isolates from chickens and turkeys, which had bee ...19826749893
attachment of mycoplasmas to host cell membranes.pathogenic mycoplasmas rarely invade the tissues or bloodstream. their adherence to epithelial cell surface, the first stage in disease, involves protein binding sites on the mycoplasmal cell membrane and receptors on the host cell membrane. strong evidence indicates that mycoplasma gallisepticum and mycoplasma pneumoniae adhere with the aid of sialic acid residues on host cells, but the data do not preclude participation by other host-cell membrane components. several studies indicate that thes ...19826812202
attachment of killed mycoplasma gallisepticum cells and membranes to erythrocytes.to correlate viability with attachment capacity, mycoplasma gallisepticum cell harvested at different growth phases and treated by various agents were tested for their capacity to attach to human erythrocytes. the results show that viability per se is not essential for m. gallisepticum attachment to erythrocytes, as cells killed by ultraviolet irradiation anmd membranes isolated by lysing m. gallisepticum cells by various means retained attachment capacity. however, treatment of the mycoplasmas ...19816796518
survey of the health and husbandry of small poultry flocks in great britain.an investigation into the health and husbandry of 15 small poultry flocks was undertaken. each flock was visited in july and a questionnaire on management practices and disease history was completed. the flocks were clinically examined and serological tests for salmonella pullorum, mycoplasma gallisepticum, m synoviae, m meleagridis, newcastle disease, infectious bursal disease, infectious bronchitis, eggdrop syndrome 76, adenoviruses and reoviruses were carried out. oesophageal and cloacal swab ...19826814044
laboratory infection of house sparrows (passer domesticus) with mycoplasma gallisepticum and mycoplasma synoviae.house sparrows were infected by aerosol with mycoplasma gallisepticum (mg) or m. synoviae (ms). mg was reisolated from 5 to 11 sparrows 10 days postinfection, but infection appeared to be temporary. mycoplasma-free chickens reared in the experimental house became infected with mg during the trial. ms was recovered from only one sparrow. serological tests were unsatisfactory for diagnosing infected birds. the results suggest that house sparrows may be temporary biological carriers of mg.19836847547
experimental infection of ducks with mycoplasma gallisepticum.specific-pathogen-free ducks 24 and 180 days old were inoculated intranasally with the s6 strain of mycoplasma gallisepticum (mg). no significant gross lesions were found in trachea, lung or air sacs at 7 or 28 days postinfection (pi). mg was recovered from the infraorbital sinus and trachea but not from the air sacs 7 and 28 days pi. a few ducks responded serologically by developing agglutinating antibody. mg multiplied in embryonated duck eggs but to lower titers than in embryonated chicken eg ...19836870721
[in vitro susceptibility of mycoplasma gallisepticum field strains to tiamulin and tylosin (author's transl)]. 19806995088
disposition of exposed antigens on the faces of isolated mycoplasma gallisepticum membranes.the transverse disposition of exposed protein antigens on the two faces of isolated mycoplasma gallisepticum membranes have been investigated by using indirect immunoferritin labeling to accomplish visualization of the antigens at the ultrastructural level. comparison between the labeling patterns obtained with unabsorbed specific mycoplasma antiserum and antiserum from which antibodies directed against outer side determinants had been removed revealed that the majority of protein antigens were ...19806991483
[clinical and pharmacological studies of technical tylosin phosphate from pharmachem in poultry diseases].investigations on the healing anbd prophylactic effectiveness of the technical tylosine phosphate "pharmachim" with 50 iu/mg activity (pharmazin t-50) in some bird diseases were carried out. it was established that a dose of 20 g/kg fodder pharmazin t-50 applied 2 days pre- and 3 days post chicken mycoplasma gallisepticum infection protects the chickens completely from respiratory mycoplasmosis. in order to attain a sure healing and prophylactic effect in hen spirohetosis control 10 g/kg fodder ...19806998102
indirect immunoperoxidase technique for the assay of antibodies against mycoplasma gallisepticum and m. synoviae in chicken serum.the indirect immunoperoxidase technique (iip) was applied to the assay of antibodies against mycoplasma gallisepticum and m. synoviae in chicken serum by using colonies grown on the agar plate as antigen. the sensitivity and the specificity of iip were evaluated by the use of sera from experimentally infected, filed, and spf chickens. as compared with tube agglutination and hemagglutination-inhibition tests, iip was highly effective and specific for detecting antibodies against m. gallisepticum ...19827043285
characterization of antigens from mycoplasmas of animal origin.alcholeplasma laidlawii, mycoplasma gallisepticum, m mycoides subsp mycoides, m agalactiae, m bovirhinis, mycoplasmal strain st-6, and culture medium were compared with m bovis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, enzyme-linked immunosorbent assay (elisa), and gel electrophoresis-derived elisa. sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated there were areas of homology and areas of heterology among the species tested. sera from rabbits hyperimmunized ...19836838038
production and persistence of antibodies in chickens to sheep erythrocytes. 2. resistance to infectious diseases.a line of chickens selected for ability to product high antibody titers to sheep red blood cells exhibited stronger antibody to newcastle disease, was more resistant to mycoplasma gallisepticum, eimeria necatrix, a splenomeglia virus, and feather mites and less resistant to escherichia coli and staphylococcus aureus infection than a line selected for a lack of ability to produce antibody titers. a line of chickens selected for a nonpersistance of antibody titers to sheep red blood cells was rela ...19806997852
viability of the f strain of mycoplasma gallisepticum after storage in the frozen or lyophilized state.strain f of mycoplasma gallisepticum was stored frozen at -60 c or -20 c in liquid medium with or without cryoprotective agents or was lyophilized with or without stabilizers and stored at 4 c. the titer was determined before, during, and after the subsequent storage period. in cultures frozen at -60 c or lyophilized, the titer had not significantly declined by the end of 371 days of storage. at -20 c, the titer of frozen cultures declined rapidly, and no mycoplasma had survived 282 days of stor ...19827049151
a comparison of alternative methods to viable count for indicating growth of mycoplasma gallisepticum in liquid culture. 19817019180
long-term exposure of chickens to three levels of social stress.cockerels were kept in environments characterized by high (hss), medium (mss), or low (lss) levels of social stress for 3 or 4 months. chickens raised in an environment of low light intensity (lss) gained more weight than did those raised under natural lighting. ability of chickens to produce antibody in response to antigen was greatly reduced, 2(15.4) in the lss group to 2(3.4) in the hss group, 1 day after chickens were moved from the lss environment into the hss environment. normal responsive ...19817020680
possible association of segregated lipid domains of mycoplasma gallisepticum membranes with cell resistance to osmotic lysis.freeze-fracturing of cholesterol-rich mycoplasma gallisepticum membranes from cells grown in a medium containing horse serum revealed particle-free patches. the patches appeared in cells quenched from either 4 or 37 degrees c. particle-free patches also occurred in membranes of cells grown in a serum-free medium supplemented with egg-phosphatidylcholine but not in membranes of cells grown with dioleoylphosphatidylcholine. the appearance of particle-free patches was attributed to the presence of ...19827054144
isolation of mycoplasma membranes by dicyclohexylcarbodiimide-induced lysis.a simple procedure was devised to prepared membranes from mycoplasma gallisepticum cells. the cells were lysed in an isosmotic nacl solution by dicyclohexylcarbodiimide, which blocks atpase activity and interferes with the regulation of cell volume. the procedure can be used to isolate membranes of other osmotically resistant mycoplasmas.19827061381
pathogenicity of two strains of mycoplasma gallisepticum in turkeys.strains f and r of mycoplasma gallisepticum (mg) were compared for their pathogenicity in broad-breasted white turkey poults in terms of induction of airsacculitis, depression of growth rate, and induction of antibody production against mg. eye-drop inoculation with the f or r strain produced only minimal lesions. however, aerosol exposure with either mg strain resulted in a significantly higher incidence and severity of air-sac lesions (p less than 0.001), reduction of growth rate (p less than ...19827103892
field evaluation of a microtitration complement-fixation test for diagnosis of mycoplasma gallisepticum in chickens.results of a direct microtitration complement-fixation (cf) test were compared with hemagglutination-inhibition (hi) test results in diagnosing mycoplasma gallisepticum (mg) infection of chickens in the field. of 16 flocks negative for mg by the hi test, eight were cf-positive. of nine flocks that were hi-positive for mg, three were cf-negative. it was concluded that the cf test is not effective in diagnosing mg infection of chickens in the field.19827103897
early detection of tracheal damage in chickens by scanning electron microscopy.fifteen-day-old chickens were inoculated with effective doses of cultured mycoplasma gallisepticum and treated with the antibiotic tiamulin or tylosin. scanning electron microscopy was used to detect early and late damages in the tracheal mucosa of the affected birds. edematous changes of various degrees were demonstrated as early as day 4 postinoculation. catarrhal changes were observed at day 10 postinoculation, and obstruction of the tracheal lumen by mucofibrinous plugs was observed at day 1 ...19827103901
low levels of mycoplasma gallisepticum or m synoviae agglutination reactors. 19827090150
detection of inhibitors in chicken tracheal washings against mycoplasma gallisepticum.a chicken tracheal ring tissue-culture system was used to demonstrate that specific and nonspecific substances in chicken tracheal secretions inhibit the cilia-stopping effect (cse) of mycoplasma gallisepticum (mg). in chickens less than six weeks old, specific inhibitory substances were found in tracheal washings from chickens inoculated with mg. nonspecific inhibitory substances were found in tracheal washes from untreated chickens seven weeks or older. complement may play a role in the inhibi ...19827092736
comparison of seven isolates of mycoplasma meleagridis.a comparative study of seven isolates of mycoplasma meleagridis indicated that they were indistinguishable morphologically. two isolates, e2 and 8m92, induced hemagglutination of red blood cells of several different species while the others did not. metabolic inhibition, growth inhibition and growth precipitation tests revealed minor differences among the seven isolates. according to these differences, isolates were divided into three groups: antiserum-sensitive isolate 1466, less sensitive isol ...19827101720
lysophospholipase-catalyzed hydrolysis of lysophospholipids in mycoplasma gallisepticum membranes.mycoplasma gallisepticum strains have a membrane-bound lysophospholipase which hydrolyzes lysophospholipid generated in these membranes by treatment with an external phospholipase. this paper studies the hydrolysis of the membranous lysophospholipids by an enzyme residing in the same membrane (intramembrane utilization) or in adjacent membranes (intermembrane utilization). to study intermembrane hydrolysis, the phospholipids of m. gallisepticum were labeled with [3h]oleic acid. membranes were pr ...19827107553
membrane proteins of mycoplasma gallisepticum.mycoplasma gallisepticum membrane proteins were separated by two-dimensional gel electrophoresis. we found no evidence for the presence of a membrane glycoprotein.19827107562
mechanism of action of the copper(i) complex of 2,9-dimethyl-1,10-phenanthroline on mycoplasma gallisepticum.evidence was found that the inhibitory action of cu(dmp)2no3, the copper(i) complex of 2,9-dimethyl-1,10-phenanthroline (dmp), on mycoplasma gallisepticum is a consequence of the ultimate toxicity of copper, and not that of the ligand, dmp. from uptake studies with radiolabeled 67cu and [14c]dmp, we concluded that significantly more copper than dmp is bound to the mycoplasmal cell. it appeared that dissociation of cu(dmp)2+ occurred shortly after interaction with the cell membrane. copper was tr ...19827114836
effects of ionophores and dicyclohexylcarbodiimide on mycoplasma gallisepticum adherence to erythrocytes.to test the influence of the electrochemical ion gradient across mycoplasma membranes on the capacity of organisms to adhere to host cells, mycoplasma gallisepticum cells were treated with valinomycin, carbonylcyanide m-chlorophenylhydrazone, and n,n'-dicyclohexylcarbodiimide (dccd) singly or in combination. uptake of [3h]tetraphenylphosphonium by the treated cells was employed as a measure of the effects of the ionophores on membrane potential. in the absence of k+, valinomycin increased, where ...19827141689
analysis of membrane fractions from mycoplasma gallisepticum.membrane fractions have been isolated from mycoplasma gallisepticum following a procedure derived from that described by maniloff, j. and quinlan, d.c. (j. bacteriol. (1974) 120, 495-501). a light fraction f1 was obtained which contained structures resembling the bleb-infrableb apparatus characteristic of m. gallisepticum. it was enriched in dna and had an electrophoretic profile different from that of unfractionated membranes. cholesterol-to-phospholipid ratios higher than two and elevated valu ...19827115712
studies of tylosin derivatives effective against macrolide-resistant strains: synthesis and structure-activity relationships.the 4"-o-substituted tylosin derivatives were prepared by selective esterification of the 4"-oh, and relationships between the substituent groups and antimicrobial activity against macrolide-resistant strains were examined. introduction of branched-chain aliphatic acyl groups such as 2-methoxyisovaleryl or 4-methylvaleryl group afforded derivatives with good antibacterial activity; mic values were 12.5 microgram/ml against staphylococcus aureus ms-8710. mic values of tylosin, erythromycin and jo ...19827118722
the electrochemical potential across mycoplasmal membranes.the electrochemical proton gradient across mycoplasmal membranes was studied. the transmembrane proton-motive potential, delta p, is composed of two parameters, a transmembrane electric potential difference, delta psi, and a transmembrane proton gradient, delta ph, according to the formula delta p = delta psi -(a x delta ph). membrane potentials were determined with use of potential-sensitive cyanine dyes. the delta psi for both mycoplasma mycoides subspecies capri and mycoplasma gallisepticum w ...19827123058
microagglutination test for the detection of antibodies to mycoplasma gallisepticum and m. synoviae in avian sera. 19827150146
egg transmission of two strains of mycoplasma gallisepticum in chickens.the egg transmissibility of strains f and r of mycoplasma gallisepticum (mg) was studied in 53 pullets by isolating mg from the eggs and embryos. mg was isolated at rates of 3.19% and 1.59% from the eggs of hens exposed by aerosol to the r or f strain, respectively. however, mg was isolated at rates of 0.19% and 0.00% from the eggs of chickens exposed by eye drop to the r or f strain, respectively. a statistically significant reduction in egg production was observed during the first 4 weeks post ...19827150143
cross-immunity and antigenic relationships among five strains of mycoplasma gallisepticum in young leghorn chickens.five strains of mycoplasma gallisepticum (mg) were tested for their cross-protection, virulence, and antigenic relationship in young leghorn chickens. chickens vaccinated at 1 day of age by eye drop with the f or r strain of mg had good protection against aerosol challenge with the f, r, or s-6 strain at 4 weeks postvaccination. chickens vaccinated at 1 day of age with the 503 or 730 strain had only partial protection against challenge with r, f, or s-6; the degree of cross-protection was relate ...19827150144
wildlife surveillance during a mycoplasma gallisepticum epornitic in domestic turkeys.during a major mycoplasma gallisepticum (mg) epornitic in domestic turkeys, tracheal swabs were collected and cultured from 477 and 770 potentially exposed wild mammals and birds, respectively. all culture attempts were negative. serum-plate (sp) and hemagglutination-inhibition (hi) tests on 770 bird sera revealed low titers (less than or equal to 1:40) in 0.9% of tested house sparrows, 1.1% of brown-headed cowbirds, 35.7% of common grackles, 1.0% of starlings, and 16.6% of eastern meadowlarks. ...19827159324
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