TitleAbstractYear(sorted ascending)
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
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
characterization and solubilization of the membrane-bound atpase of mycoplasma gallisepticum.the membrane-bound atpase of mycoplasma gallisepticum selectively hydrolyzed purine nucleoside triphosphates and datp. adp, although not a substrate, inhibited atp hydrolysis. the enzyme exhibited a ph optimum of 7.0 to 7.5 and an obligatory requirement for divalent cations. dicyclohexylcarbodiimide at a concentration of 1 mm inhibited 95% of the atpase activity at 37 degrees c, with 50% inhibition occurring at 22 microm dicyclohexylcarbodiimide. sodium or potassium (or both) failed to stimulate ...19853161871
evaluation of cytopathologic changes induced in chicken tracheal epithelium by mycoplasma gallisepticum in vivo and in vitro.changes in tracheal epithelial surfaces induced by mycoplasma infection in vivo and in vitro included release of mucous granules followed by exfoliation of ciliated and nonciliated epithelial cells. light microscopy, scanning electron microscopy, and transmission electron microscopy confirmed that the loss of cilia from individual cells was infrequent. epithelial cells typically lost their intercellular connections, rounded up, exfoliated, and then lysed--giving rise to a population of cellular ...19853970413
evaluation of serologic tests for mycoplasma gallisepticum in wild turkeys. 19853981747
in ovo pathogenicity of mycoplasma gallisepticum strains in the presence and absence of maternal antibody.mycoplasma gallisepticum (mg) strains showing marked variation in pathogenicity were examined for virulence in ovo. no correlation was found between in ovo pathogenicity and other in vivo or in vitro methods for pathogenicity evaluation. for certain highly pathogenic strains, there was a clear relationship between the titer of mg inoculated and the embryo mortality and time of death; an ld50 for these strains could be calculated by yolk-sac inoculation. however, not every strain that caused lesi ...19853985874
an enzyme-linked immunosorbent assay for the detection of antibodies to mycoplasma gallisepticum in experimentally infected indirect enzyme-linked immunosorbent assay (elisa) was developed and tested for its ability to detect humoral response to mycoplasma gallisepticum in chickens. two antigens were used in the solid phase of the assay. antigen 1 was a membrane-derived sodium dodecyl sulfate (sds)-solubilized preparation; antigen 2 was prepared in the same manner as antigen 1 but was passed through an immunoadsorbent column containing rabbit anti-medium antibodies. test conditions were optimized for incubation ti ...19853985883
kinetics of cholesterol and phospholipid exchange from membranes containing cross-linked proteins or cross-linked phosphatidylethanolamines.mono- and dipalmitoylphosphatidylethanolamine derivatives have been synthesized and used to evaluate the role of cross-links between the amino groups of two phospholipid molecules in the rate of cholesterol movement between membranes. incorporation of the cross-linked phospholipids into small unilamellar vesicles (the donor species) decreased the rate of spontaneous cholesterol exchange with acceptor membranes (small unilamellar vesicles or mycoplasma gallisepticum cells). these results suggest ...19853986182
comparison of the antimycoplasma activity of two commercially available tylosin premixes.two tylosin premixes (referred to in this report as premix a and tylosin premix b), obtained as commercial products from japan, were analyzed microbiologically for tylosin and by high pressure liquid chromatography (hplc) for macrolide content. they were evaluated in the feed at concentrations of 550 and 1100 ppm antibiotic activity for the treatment of chickens with induced mycoplasma gallisepticum (mg) infection. the tylosin microbiological assay value for premix a was 3.0% below and for premi ...19853991415
mycoplasma gallisepticum vaccination: further studies on egg transmission and egg production.leghorn hens vaccinated twice with an inactivated mycoplasma gallisepticum (mg) bacterin before egg production and subsequently challenged with virulent mg were protected against transmission of mg through the egg. unvaccinated control hens transmitted mg through the egg at a high rate. when unvaccinated hens were vaccinated with mg bacterin 2 weeks after challenge with mg, there was no significant decrease in egg transmission. hens vaccinated twice before laying did not suffer as severe egg-pro ...19854026735
cell volume regulation in mycoplasma gallisepticum.mycoplasma gallisepticum cells incubated in 250 mm nacl solutions in the absence of glucose showed a progressive fall in intracellular atp concentration over a period of 2 to 3 h. when the atp level fell below 40 microm the cell began to swell and become progressively permeable to [14c]inulin and leak intracellular protein and nucleotides. the addition of nondiffusable substances such as mgso4 or disaccharides prevented swelling, suggesting that nacl (and water) entry was due to gibbs-donnan for ...19854030694
sodium and proton transport in mycoplasma gallisepticum.when washed cells of mycoplasma gallisepticum were incubated at 37 degrees c in 250 mm 22nacl, the intracellular na+ increased, and the k+ decreased. the addition of glucose to these na+-loaded cells caused na+ efflux and k+ uptake (both ions moving against concentration gradients). this effect of glucose was blocked by the atpase inhibitor dicyclohexylcarbodiimide, which prevents the generation of a proton motive force in these cells. in additional experiments, na+ extrusion was studied by dilu ...19854030695
presumptive diagnosis of subclinical infections utilizing computer-assisted analysis of sequential enzyme-linked immunosorbent assays against multiple serum samples, collected sequentially from four flocks of egg- and meat-type chickens, were evaluated for antibodies to multiple infectious agents by enzyme-linked immunosorbent assay (melisa). the melisa system used provided simultaneous measurement of antibody titers against avian infectious bronchitis (ib), infectious bursal disease (bd), newcastle disease, avian encephalomyelitis and reovirus infections, and mycoplasma gallisepticum. the use of computer-generated grap ...19854048057
egg production, egg weight, eggshell strength, and mortality in three strains of commercial layers vaccinated with f strain mycoplasma gallisepticum.three strains of commercial leghorns vaccinated at 17 to 22 weeks of age with f strain mycoplasma gallisepticum (mg) were maintained through 117 weeks of age. the three strains differed in both mortality and percent egg production per hen housed; however, the strains did not differ in egg weight (ew), eggshell strength (ess), or percent daily egg production. results of this study indicate ew and ess for f strain mg-vaccinated hens follow patterns previously reported for uninfected layers. furthe ...19854074249
detection of mycoplasma gallisepticum by direct immunofluorescence using a species-specific monoclonal antibody.a monoclonal antibody against mycoplasma gallisepticum (mg) (strain s6) was prepared in mice and identified as isotype igg1 by standard procedures. although it did react at high titers (1:100,000) in the enzyme-linked immunosorbent assay (the original method for its identification), it failed to react in the agglutination, hemagglutination-inhibition, and growth-inhibition tests. when conjugated to fluorescein isothiocyanate, the monoclonal antibody reacted with the homologous and eight "atypica ...19863524541
detection and differentiation of mycoplasma gallisepticum and m. synoviae antibodies in chicken serum using enzyme-linked immunosorbent assay.affinity-purified sheep igg anti-chicken igg horseradish peroxidase conjugate was utilized in an enzyme-linked immunosorbent assay (elisa) to detect mycoplasma gallisepticum- and m. synoviae-specific antibodies in chicken sera. antigen, conjugate and substrate concentrations, and incubation times were adjusted to provide maximum differentiation between positive and negative sera. use of phosphate-buffered saline containing 0.05% tween 20 for washing and diluting steps and use of normal sheep ser ...19863729859
evaluation of protection against mycoplasma gallisepticum infection in chickens vaccinated with the f strain of m. gallisepticum.the effect of vaccination with the f strain of mycoplasma gallisepticum (mg) on protection against challenge with a tylosin-resistant strain of mg was evaluated. white leghorn chickens vaccinated via eyedrop at 6 weeks of age were subsequently challenged with various dilutions of the tylosin-resistant mg strain, as were unvaccinated controls. three days later, tracheal swabs were collected and cultured in medium with and without tylosin to distinguish between the vaccine and challenge strains. t ...19863729860
triton x-100-solubilized mycoplasma gallisepticum and m. synoviae elisa antigens.triton x-100-solubilized mycoplasma gallisepticum and m. synoviae elisa antigens were found to be more specific and sensitive than six other antigens at a concentration of 250 ng protein/0.1 ml per microtiter plate well.19863729864
infectious sinusitis in coturnix quails in brazil, mycoplasmas were isolated from the sinuses of japanese quails (coturnix coturnix japonica) from two commercial flocks affected with sinusitis. the major respiratory signs and gross lesions are described. based on serological and biochemical results, the mycoplasmas isolated were identified as mycoplasma gallisepticum. one of the isolates was pathogenic for chickens.19863729866
observations on commercial layers vaccinated with mycoplasma gallisepticum (mg) bacterin on a multiple-age site endemically infected with mg.a commercially available inactivated mycoplasma gallisepticum (mg) bacterin was administered to chickens on a multiple-age farm endemically infected with mg. a total of 3400 mg-free pullets were vaccinated with the mg bacterin at 19 weeks of age, and 4300 unvaccinated pullets served as controls. the vaccinated group became serologically positive by the rapid plate agglutination (rpa) test within 3 weeks, and the unvaccinated group became positive in 7 weeks. the hemagglutination-inhibition test ...19863729876
response of chickens to inoculation with a temperature-sensitive mutant of mycoplasma gallisepticum.newly hatched chickens were inoculated intranasally with either the s6 or ts 100 strain of mycoplasma gallisepticum (mg) or they were left uninoculated. the three groups of chickens did not differ discernibly in body, spleen, or bursa weight during the 27-day sampling period. however, the s6-inoculated chickens showed a more pronounced cellular response in the nasal passages and had nearly complete lymphoid depletion in the spleens. the ts 100-inoculated birds expressed only a mild cellular reac ...19863729884
a statistical model to optimize enzyme-linked immunosorbent assay parameters for detection of mycoplasma gallisepticum and m. synoviae antibodies in egg enzyme-linked immunosorbent assay (elisa) was developed to quantify mycoplasma gallisepticum (mg) and m. synoviae (ms) antibodies in egg-yolk extract. various parameters of elisa were evaluated and optimized. a statistical model was developed to study the relationship between elisa absorbance (a) and antigen concentration, antibody concentration, and time of reading of the test. these factors explained 62% of the variability in a for the mg antigen and 74% of the variability in a for the ms a ...19863729885
comparison of egg yolk and serum for the detection of mycoplasma gallisepticum and m. synoviae antibodies by enzyme-linked immunosorbent assay.egg yolk was evaluated in the enzyme-linked immunosorbent assay (elisa) as an alternative source of antibodies for detection of mycoplasma gallisepticum (mg) and m. synoviae (ms) infections in chickens. there was no statistically significant difference (p greater than 0.05) between the elisa geometric mean titers (gmts) of saline-diluted egg yolk and chloroform-extracted egg yolk, and both preparations had a high correlation coefficient (0.87 for mg; 0.97 for ms). the saline-diluted and chlorofo ...19863729886
31p-nmr studies of mycoplasma gallisepticum cells using a continuous perfusion technique.31p-nmr studies of mycoplasma gallisepticum cells have been carried out using a continuous perfusion technique; these are the first such studies with this organism. using this technique, glucose metabolism was monitored in the intact organisms, and cell extracts were prepared to identify the intermediates. under glycolytic conditions, high levels of fructose-1,6-diphosphate were observed, indicating that this sugar may play a key role in the regulation of metabolism. the level of phosphoenolpyru ...19863732520
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
infectious sinusitis associated with mycoplasma gallisepticum in game-birds. 19863753348
prophylactic efficacy of 3-acetyl-4''-isovaleryl tylosin in a mycoplasma gallisepticum-induced airsacculitis infection.formulations of 3-acetyl-4''-isovaleryl tylosin (aiv) were evaluated for oral efficacy in a mycoplasma gallisepticum (mg) airsacculitis infection. aiv administered by gavage, feed, or water was more effective than tylosin in preventing airsacculitis. an aiv tartrate formulation administered in drinking water to chickens infected with a macrolide-sensitive or macrolide-resistant strain of mg resulted in no detection of mycoplasma in the air sacs and in mg-negative sera.19863767811
a historical account of the diagnosis and characterization of strains of mycoplasma gallisepticum of low virulence.numerous chicken flocks were studied beginning in 1970 because of questionable results on their serologic tests for mycoplasma gallisepticum (mg). typically a low number of hens in the flocks were positive reactors to the rapid serum plate test and rarely had hemagglutination-inhibition (hi) titers over 1:80. usually no clinical signs were observed. isolates of mg eventually were cultured from most of the flocks that exhibited that type of marginal serologic pattern. in the laboratory, the mg is ...19863767812
prevalence of mycoplasma gallisepticum and m. synoviae in commercial layers in southern and central california.the prevalence of mycoplasma gallisepticum (mg) and m. synoviae (ms) in commercial pullet and layer flocks in southern and central california was estimated by testing serum and egg-yolk samples from 360 sample flocks in southern california and 41 sample flocks in central california. data relating to potential risk factors associated with mg and ms infections were collected. the estimated true prevalence rate of mg was 73% in southern california and 3% in central california. the estimated true pr ...19863767813
antibody responses in sera and respiratory secretions from chickens infected with mycoplasma gallisepticum.antibodies in sera and respiratory secretions from chickens infected with mycoplasma gallisepticum (mg) were measured by an enzyme-linked immunosorbent assay (elisa). chickens intratracheally inoculated with 10(5) cells of mg showed a correlation between severity of tracheal lesions and extent of mg colonization in the tracheas in the first 3 weeks postinoculation. antibody titers in tracheal washings (tws) of the infected chickens increased during this phase. thereafter, isolation of mg from th ...19863767815
effect of medicated feed on tracheal infection and population of mycoplasma gallisepticum in chickens.six-week-old broilers were fed 50 g tylosin/ton, 400 g chlortetracycline (ctc)/ton, or unmedicated feed and then challenged intratracheally with r strain mycoplasma gallisepticum (mg). feed-grade antibiotic medication did not prevent infection, but medication did lower the number of isolations from treated birds compared with controls. only tylosin significantly lowered mg counts in the trachea. the log10 id50 of birds receiving tylosin, ctc, or unmedicated feed were 5.8, 4.4, and 2.9, respectiv ...19863767816
a radioimmunoassay for the detection of antibodies to mycoplasma gallisepticum.a radioimmunoassay technique was developed to determine the antibodies to mycoplasma gallisepticum (mg) in sera, yolk fluids, and tracheal washings.19863767822
properties of mycoplasma gallisepticum grown in a medium supplemented with liposomes as a substitute for serum. 19863796324
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
influence of hatcher holding times on several physiological parameters associated with the immune system of chickens.two experiments were conducted with broiler chicks to study the effects of posthatch holding time in the incubator on physiological and disease parameters. in each experiment, half of the chicks were removed shortly after hatching and half of the chicks were allowed to remain in the hatcher for an additional 30 hr. bursa weights, hematocrits, total plasma protein, and blood glucose concentrations were measured at various times up to 35 and 28 days of age in experiments 1 and 2, respectively. in ...19863822996
the beta-subunit of the f1f0-atpase is conserved in mycoplasmas.monospecific polyclonal antibodies that were generated against the beta-subunit of escherichia coli atpase (f1fo) cross-reacted with a protein present in the cells of several mycoplasma and acholeplasma species. in mycoplasma gallisepticum, the reactive protein was found almost exclusively in the cell membrane. this protein had an apparent molecular mass of approximately 52 kda and could not be released from the membranes by repeated washings with either low or high salt solutions in the presenc ...19862872212
interaction of albumin and phospholipid:cholesterol liposomes in growth of mycoplasma spp.mycoplasma spp., sterol and fatty acid auxotrophs, are conventionally grown in complex media containing high concentrations of serum. serum supplies the required lipids, but its presence complicates studies on the metabolism and antigenicity of mycoplasmas as well as the membrane dynamics of these organisms. in the present work, fetal bovine serum was replaced with dilipidated albumin and liposomes containing high concentrations of cholesterol. the liposomes were produced from phosphatidylcholin ...19863954343
antigenic determinants of the attachment protein of mycoplasma pneumoniae shared by other pathogenic mycoplasma previous studies with hyperimmune rabbit antisera, we found evidence of serologic cross-reactivity among mycoplasma pneumoniae, mycoplasma genitalium, and mycoplasma gallisepticum. because of certain biologic and morphologic similarities of these species, attempts were made to determine if this cross-reactivity related to the attachment protein (p1) of m. pneumoniae. monoclonal and monospecific antibodies against p1 were used to probe proteins of the other species by immunoblotting. one of th ...19862417956
pathological and immunological studies on chicken embryos and day-old chicks experimentally infected with mycoplasma gallisepticum. 19862953204
comparison of in vivo and in vitro methods for pathogenicity evaluation for mycoplasma gallisepticum in respiratory infection.this study was designated to examine the pathogenicity of several strains of mycoplasma gallisepticum (r, f, s-6, 227 and a5969) and laboratory derived substrains. preliminary results indicated that the nine m. gallisepticum strains differed markedly in their pathogenicity for chickens. a comparison was made between various in vivo and in vitro methods for quantitative evaluation of pathogenicity. reproducibility, convenience, and relevance to clinical observations were considered. two in vivo t ...198618766523
isolation of mycoplasma gallisepticum from geese.two breeding flocks of 2-year-old geese in the landes region of southwest france were cultured for mycoplasmas. in one flock of 134 birds mycoplasma gallisepticum was isolated from three individuals, from a different site in each bird (i.e. oesophagus, trachea, cloaca). m. gallisepticum was also isolated from the semen of one goose in the other flock of 70 birds, but in neither flock could the true incidence be determined because of prolific overgrowth by acholeplasmas in nearly all the samples.198618766559
an inactivated temperature-sensitive mycoplasma gallisepticum mutant for protection against airsacculitis.a formalinised temperature-sensitive (ts) mutant of mycoplasma gallisepticum (mg) emulsified in complete freund's adjuvant was capable of protecting chickens against airsacculitis after intra-air sac challenge with the virulent s6 strain at a statistically significant level. formalinised ts mg vaccine without the addition of adjuvant yielded inconsistent results, and the outcome may have been dependent upon the dosage used.198718766639
control of sodium fluxes in mycoplasma gallisepticum.swelling of mycoplasma gallisepticum cells when incubated in a glucose-free isoosmotic nacl buffer was shown to be due to the entrance of nacl into the cell. volume regulation therefore depends on na+ extrusion. the mechanism of na+ extrusion in cells and proteoliposomes, prepared from m. gallisepticum membrane fragments, was investigated by following both 22na+ efflux and ph changes. our results indicate that na+ is expelled from cells via two separate mechanisms, an na+/cation exchange mechani ...19872822608
synthesis of deoxyribomononucleotides in mollicutes: dependence on deoxyribose-1-phosphate and ppi.cell extracts of acholeplasma laidlawii b-pg9, acholeplasma morum s2, mycoplasma capricolum 14, and mycoplasma gallisepticum s6 were examined for 37 cytoplasmic enzyme activities involved in the salvage and biosynthesis of purines. all of these organisms had adenine phosphoribosyltransferase activity (ec and hypoxanthine phosphoribosyltransferase activity (ec all of these organisms had purine-nucleoside phosphorylase activity (ec in the synthetic direction using ribos ...19873038846
[detection and identification of mycoplasma infections by dna hybridization].infection of cell cultures by mycoplasmas can be detected by hybridization of the dna of suspected cell cultures with recombinant plasmids containing fragments of the mycoplasma dna. the test is very sensitive and allows detection of as little as 1 ng of mycoplasmal dna, roughly equivalent to the dna amount of 10(6) mycoplasmas. this approach turns out to be effective for detection and identification of mycoplasmas in clinical material, plant and insect tissues. a set of dna probes for detection ...19873318046
investigation into the mechanism of copper uptake by mycoplasma gallisepticum in the presence of 2,9-dimethyl-1, the presence of copper certain 2,2'-bipyridyls show antimycoplasmal activity, whereas copper itself causes a toxic effect. in this paper results are presented to elucidate the mechanism of copper uptake in the presence of 2,9-dimethyl-1,10-phenanthroline. the time course of copper and/or ligand uptake under the applied conditions is consistent with a carrier transport mechanism in which 2,9-dimethyl-1,10-phenanthroline operates as a carrier for copper ions. the influence of valinomycin on cop ...19873432040
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
effect of mycoplasma gallisepticum bacterin on egg-transmission and egg production.groups of white leghorn hens were vaccinated twice with a mycoplasma gallisepticum (mg) bacterin, once with bacterin, or left unvaccinated. four weeks after vaccination, they were challenged with virulent r strain mg. egg production was significantly higher in challenged vaccinated groups than in the challenged control group. four challenged control hens went out of production, whereas only one twice-vaccinated hen did. mg was first isolated directly from eggs 5 days postchallenge (pc) in twice- ...19873442529
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
a mycoplasma gallisepticum strain-specific dna dna from the vaccine f strain (k810) and the reference s6-strain of mycoplasma gallisepticum (mg) was cloned in escherichia coli using the plasmid puc8. a 6-kilobase fragment, specific for the vaccine strain, was identified by colony dot and southern hybridization analyses. when labeled and used as a probe, this fragment hybridized with the homologous and one other vaccine f-strain (f2f10), but it did not hybridize with other mg strains (fg38, s6, a5969, v503) or with three other species o ...19873442542
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
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
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
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
mycoplasma gallisepticum strain variations detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.various strains of mycoplasma gallisepticum (mg) were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. minor but distinct and reproducible differences in protein banding patterns were detected between strains, which included the vaccine f strain from various sources, an atypical (variant) strain, and the standard (a5969, s6) strains.19873619825
evaluation of respiratory lesions in chickens induced by mycoplasma gallisepticum. 19873626242
inhibition of nadh oxidase and lactate dehydrogenase of mycoplasma gallisepticum by copper complexes of 2,2'-bipyridyl the presence of copper, 2,2'-bipyridyl analogues possess growth-inhibitory activity against mycoplasma gallisepticum. inhibition of the energy yielding metabolism plays a role in the mechanism of action. we showed that probably inhibition of lactate dehydrogenase and nadh oxidase is involved. both enzymes were inhibited in vitro and in vivo by several copper 2,2'-bipyridyl complexes. a two-step mechanism of action is proposed, i.e. first a copper complex enters the cell, then after dissociati ...19873663238
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
sealed vesicles prepared by fusing mycoplasma gallisepticum membranes and preformed lipid vesicles.sealed vesicles were obtained by fusing mycoplasma gallisepticum membranes with asolectin-cholesterol vesicles. the fusion was induced by freezing and thawing followed by a brief sonication treatment and was detected using a fluorescence sedimentation behavior in a sucrose density gradient and were shown to be impermeable to small solutes. the advantages of such fused preparations for transport studies in mycoplasmas are discussed.19873667215
kinetics of cholesterol and phospholipid exchange between mycoplasma membranes and lipid vesicles.the following modifications in the lipid composition of mycoplasma gallisepticum or m. capricolum membranes led to changes in the rates of [14c]cholesterol and [14c]phospholipid exchange between cell membranes and an excess of small unilamellar vesicles: 1) increase in the cholesterol/phospholipid molar ratio from 0.25 to 0.92; 2) incorporation of synthetic, cross-linked phosphatidylethanolamine (pe) derivatives, 3) incorporation of sphingomyelin (spm); and 4) increase in the phosphatidylglycero ...19873667216
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
evaluation of factors associated with infection of commercial layers with mycoplasma gallisepticum and m. synoviae.information on factors possibly associated with the risk of infection with mycoplasma gallisepticum (mg) or m. synoviae (ms) were collected from nearly 400 layer flocks in california. factors associated with the probability of flock infection with either mg or ms were identified, and their magnitude was quantified by statistical analysis. more frequent administration of several vaccines was associated with decreased probability of both mg and ms infection of flocks. also identified were housing ...19873675422
economic impact of mycoplasma gallisepticum and m. synoviae in commercial layer egg-production function was constructed, using data collected from 366 commercial layer flocks in california, to predict the impact of mycoplasma gallisepticum (mg) and m. synoviae (ms) on egg production while controlling for confounding factors. in the first and second cycles, respectively, an mg-infected flock produced 12 and 5 fewer eggs per hen than an uninfected flock. flocks that became infected with mg after f-strain vaccination produced 6 eggs/hen more than unvaccinated infected flock ...19873675423
comparison of culturing mycoplasma gallisepticum from fresh eggs and 18-day-old embryos.twenty-four 70-week-old and sixteen 27-week-old white leghorn hens were challenged with r strain mycoplasma gallisepticum (mg) by injection into the caudal thoracic air sac and infraorbital sinus. eggs were collected daily and cultured within 7 days or incubated for 18 days. vitelline membranes of eggs were cultured directly; in 18-day-old embryos, cultures were taken from the yolk sac, air sacs, and oral cavity. culture of vitelline membrane of eggs within 2 days was compared with culture of eg ...19873675426
serological monitoring of eastern wild turkeys for antibodies to mycoplasma spp. and avian influenza viruses.from 1981 through 1986, plasma or serum samples were obtained from 322 wild turkeys (meleagris gallopavo) from georgia (n = 111), kentucky (n = 21), louisiana (n = 22), north carolina (n = 118), tennessee (n = 19), missouri (n = 24) and iowa (n = 7). these samples were tested for antibodies to mycoplasma gallisepticum (mg) and in most instances, m. synoviae (ms), m. meleagridis (mm), and avian influenza (ai) virus. all 322 turkeys were seronegative for mg by the rapid plate agglutination (rpa) t ...19883373642
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
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
experimental mycoplasma gallisepticum infections in captive-reared wild turkeys.the effects of mycoplasma gallisepticum (mg) infections on egg production, fertility, and hatchability were studied in captive-reared wild turkeys (meleagris gallopavo). three groups of adult birds, each consisting of four hens and two toms, were exposed to mg by the respiratory route at the beginning of their breeding season. fourteen control birds received sterile growth medium. although no mortality of infected or control birds occurred, egg production during the first breeding season after i ...19883411710
a pathologic study of wild turkeys in connecticut.during the 1984 to 1986 spring hunting seasons in connecticut, viscera from 300 hunter-killed wild turkeys and blood samples from live-trapped wild turkeys were examined in order to establish a health profile on the state's wild turkey population. seven species of endoparasites were recovered from 224 (75%) of 300 birds: metroliasthes lucida, ascaridia dissimilis, heterakis gallinarum, syngamus trachea, capillaria species, trichomonas gallinarum, and eimeria species. the most prevalent parasites ...19883168472
serologic response of rio grande wild turkeys to experimental infections of mycoplasma gallisepticum.the serologic response of rio grande wild turkeys (meleagris gallopavo intermedia) to mycoplasma gallisepticum (mg) was determined. free-ranging turkeys were caught in southern texas, shipped to the university of wisconsin, madison, and housed in isolation facilities. fourteen birds were exposed to mg, by intratracheal and intranasal inoculation. eight birds received sterile broth only. two wk prior to the end of the experiment, mg exposed turkeys were stressed by challenge with a serologically ...19883193562
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
species-specific biotinylated dna probe for the detection of mycoplasma gallisepticum.a 5.5 kilobase dna fragment from an eco ri digest of the mycoplasma gallisepticum genome was specific for the detection of m. gallisepticum. this 5.5 kb fragment was initially cloned into bacteriophage lambda gt11 followed by subcloning into the plasmid vector pgem-3z. the incorporation of a biotin label was accomplished by utilizing biotin-11-dutp in a nick translation reaction. this probe, designated pmg6, reacts specifically with m. gallisepticum when tested against various mycoplasma dnas in ...19883221885
rapid identification of mycoplasma gallisepticum using a simple method of nucleic acid hybridization. 19883247004
lectin-induced damage to the enterocyte brush border. an electron-microscopic study in rabbits.the ultrastructural effects of 11 lectins on the intestinal brush border were examined by means of an in vitro rabbit ileal mucosal explant culture system. five of the lectins that bind to oligosaccharides containing either n-acetylglucosamine (phytohaemagglutinin, euonymus europaeus lectin, pokeweed mitogen, and wheat germ agglutinin) or n-acetylneuraminic acid (mycoplasma gallisepticum lectin) all had a specific effect on microvilli. the effects varied in accordance with the lectin and include ...19883249912
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
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
identification of mycoplasma gallisepticum and m. synoviae by flow cytometry.immunofluorescence and flow cytometric methods were examined to detect and distinguish mycoplasma gallisepticum and m. synoviae. the procedure employed 24-hr broth cultures of each organism, direct immunofluorescence staining with either homologous or heterologous antiserum, and analyses by flow cytometry. the organisms were distinguishable on the basis of fluorescent profiles when stained with the appropriate antiserum.19883058112
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
presence of anaplerotic reactions and transamination, and the absence of the tricarboxylic acid cycle in mollicutes.cell extracts of the fermentative mollicutes acholeplasma laidlawii b-pg9, acholeplasma morum s2, mycoplasma capricolum 14, mycoplasma gallisepticum s6, mycoplasma pneumoniae fh, mycoplasma hyopneumoniae j and m. genitalium g-37, and the non-fermentative mycoplasma hominis pg-21, mycoplasma hominis 1620 and mycoplasma bovigenitalium pg-11 were examined for 39 cytoplasmic enzyme activities associated with the tricarboxylic acid (tca) cycle, transamination, anaplerotic reactions and other enzyme a ...19883141576
animal viruses are able to fuse with prokaryotic cells. fusion between sendai or influenza virions and mycoplasma.sendai and influenza virions are able to fuse with mycoplasmata. virus-mycoplasma fusion was demonstrated by the use of fluorescently labeled intact virions and fluorescence dequenching, as well as by electron microscopy. a high degree of fusion was observed upon incubation of both virions with mycoplasma gallisepticum or mycoplasma capricolum. significantly less virus-cell fusion was observed with acholeplasma laidlawii, whose membrane contains relatively low amounts of cholesterol. the require ...19882826447
ribosomal rna gene probes to detect intraspecies heterogeneity in mycoplasma gallisepticum and m. synoviae.intraspecies genotypic heterogeneity among strains of mycoplasma gallisepticum and m. synoviae was tested using genomic fingerprints with a ribosomal rna (rrna) gene probe. the organism's dna was digested by a restriction endonuclease, electrophoresed, transferred to a nitrocellulose sheet, and hybridized with 32p-labeled pmc5 plasmid carrying the highly conserved rrna genes of m. capricolum. the resulting hybridization patterns indicated a degree of genotypic heterogeneity among m. gallisepticu ...19882840880
protein phosphorylation in mycoplasma gallisepticum.incubation of the soluble fraction derived from mycoplasma gallisepticum cells with [gamma-32p]atp results in the phosphorylation of several endogenous proteins. one protein with an apparent molecular mass of 55 kda was the acceptor of more than 95% of the radioactive phosphate. this protein was also found to be radiolabeled in intact cells grown in the presence of [32p]orthophosphate. acid hydrolysis of the phosphorylated 55-kda protein followed by two-dimensional electrophoresis revealed that ...19882843367
comparison of mycoplasma gallisepticum strains by hemagglutination-inhibition and restriction endonuclease analysis.mycoplasma gallisepticum strains, including a series of field strains from north carolina, were examined by homologous and heterologous hemagglutination-inhibition (hi) tests and by restriction endonuclease dna analysis to determine whether they were closely related. hi results indicated wide antigenic diversity. generally, homologous hi titers were higher than heterologous titers; exceptions were probably due to relative insensitivity of individual antigen batches. strain a5969, commonly used a ...19882849403
intraspecies genotypic heterogeneity among mycoplasma gallisepticum strains.the dna cleavage patterns and protein profiles of six mycoplasma gallisepticum strains from various parts of the world were compared. obvious differences among the strains were obtained by dna restriction analysis. reflection of genotypic variations in the polypeptide patterns was less pronounced; slight differences in the protein profiles of the strains were found. the data presented here indicate that some intraspecies polymorphism exists among m. gallisepticum strains.19882895605
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
natural infection of ducks with mycoplasma synoviae and mycoplasma gallisepticum and mycoplasma egg transmission.mycoplasma gallisepticum (mg), m. synoviae (ms), m. cloacale (mc) and m. anatis were isolated from ducks kept in a yard in close contact with chickens that were infected with mg, ms and some other avian mycoplasma species. mg, ms and mc were isolated also from embryonated duck eggs and from infertile duck eggs laid during the first four weeks of egg production. infected ducks did not show clinical signs of mg or ms infection in chicken. detectable mg and ms agglutinating antibodies were not pres ...198818766701
examination of mycoplasma gallisepticum strains using restriction endonuclease dna analysis and dna-dna hybridisation.dna from 10 mycoplasma gallisepticum strains and one strain each of m. synoviae and m. gallinarum were studied by restriction endo-nuclease dna analysis using endonucleases eco ri, hindiii, bglii, bamhi, kpni, and xhoi. digestion patterns of dna in agarose gels allowed easy differentiation of m. gallisepticum strains from different sources, while patterns obtained from one strain at the 6th and 100th in vitro passage levels were identical. the f strain and a field derivative obtained from a poul ...198818766716
[experimental infection with mycoplasma gallisepticum: influence of ammonia as an exacerbating factor].five-week-old spf chickens were inoculated with a virulent strain of m. gallisepticum and half were exposed to an atmosphere containing 100 ppm ammonia. the inoculation reduced weight gain and induced general and respiratory signs (prostration, tracheal rales, and snoring). tracheal cilial movement was stopped. the severity and duration of m. gallisepticum infection were exacerbated by exposure to ammonia.198818766719
pathogenicity for chickens of six strains of mycoplasma gallisepticum isolated from various birds.pathogenicity of the type strain and five field strains of mycoplasma gallisepticum isolated from various avian hosts was evaluated by chicken inoculation. only two field strains isolated from chickens were highly pathogenic for the chicken respiratory tract.198818766728
natural infection of geese with mycoplasma gallisepticum and mycoplasma synoviae and egg transmission of the mycoplasmas.mycoplasma gallisepticum (mg) and m. synoviae (ms) were isolated from geese kept for more than a year on a multiple-age chicken farm. agglutinating antibodies against mg and ms were found in the sera of some geese which were positive also in the haemagglutination-inhibition tests. the isolation of mg and ms from several organs of goose embryos indicates that egg transmission occurs. it is probably the first report concerning isolation of ms from the naturally infected geese and furthermore conce ...198818766753
mycoplasma gallisepticum species and strain-specific recombinant dna probes.genomic libraries of vaccine (f-k810) and wild type (s6) mycoplasma gallisepticum were constructed in escherichia coli (strain jm83) using the plasmid vector puc8. recombinant clones were screened by colony, dot and southern hybridisations using 32p-labelled genomic dna from m. gallisepticum strains k810 and s6. eight clones were identified which contained dna sequences specific to m. gallisepticum and one clone was identified which contained a dna fragment unique to the vaccine strain (f-k810) ...198918679844
the use of a specific dna probe for detection of mycoplasma gallisepticum in field outbreaks.a specific dna probe (pmg4) was used to diagnose m. gallisepticum (mg) infection in field outbreaks in chicken and turkey breeder flocks in israel. dot-blot hybridisation of tracheal swab suspensions with the probe enabled positive identification of mg as early as 4 days after sampling, even in flocks at an early stage of infection when no other specific indications of infection were available.198918679883
effects of baytril, tylosin and tiamulin on avian mycoplasmas.the minimum inhibitory concentration (mic) of baytril, tylosin and tiamulin for strains of mycoplasma gallisepticum (mg) m. synoviae (ms), m. meleagridis (mm) and m. iowae (mi) and serovars were compared. in general the lowest mic for mg, ms and mi was obtained with baytril, while for mm both baytril and tiamulin gave the lowest mics. protection against mortality was best attained with baytril for broiler chicks and poults but against prevention of growth depression baytril was best for broiler ...198918679898
genetic and antigenic relatedness between mycoplasma gallisepticum and mycoplasma synoviae.the two avian pathogens mycoplasma gallisepticum and mycoplasma synoviae were found, by southern blot hybridization of their digested dnas, to share genomic nucleotide sequences additional to those of the highly conserved ribosomal rna genes. the assumption that some of the shared sequences encode for antigens or epitopes common to both mycoplasmas was supported by western immunoblot analysis of cell proteins of one mycoplasma with specific antiserum to the other mycoplasma. interestingly, the b ...19892466367
further studies of mycoplasma gallisepticum serum plate agglutination antigen grown in medium with artificial liposomes substituting for serum.frey's medium supplemented with artificial liposomes substituting for serum was evaluated for mycoplasma gallisepticum (mg) serum plate agglutination (spa) antigen. antigens prepared in batch (static) culture were compared with antigens grown in a fermenter. all batch-grown mg liposome antigens were highly sensitive, specific, and resulted in a greater yield compared with fermenter-grown liposome antigens. compared with antigens prepared in frey's medium with 12% swine serum (regular fms) or wit ...19892467643
biological activities of monoclonal antibodies to mycoplasma pneumoniae membrane glycolipids.a purified preparation of membranes was obtained by using a unique method of treating mycoplasma pneumoniae with the atpase inhibitor, diethylstilbestrol. this method was shown to yield highly purified membranes with little or no cytoplasmic contamination. these membranes were used to immunize mice for subsequent productions of monoclonal antibodies (mabs). hybridoma culture supernatants were screened by enzyme-linked immunosorbent assay with whole-cell m. pneumoniae and lipid extract antigens. ...19892494111
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
[antimycoplasmal activities of ofloxacin and commonly used antimicrobial agents on mycoplasma gallisepticum].in vitro activities of ofloxacin (oflx), a new quinolone derivative, against 29 strains of mycoplasma gallisepticum was compared with those of 4 commonly used antimicrobial agents, doxycycline (doxy), tylosin (ts), spectinomycin (spcm) and thiamphenicol (tp). antimycoplasmal activities of the drugs were evaluated on the mic (final mic) and mpc (minimum mycoplasmacidal concentration) values which were determined by a broth dilution procedure. the following results were obtained. 1. the mic90s of ...19892526260
volume regulation in mycoplasma gallisepticum: evidence that na+ is extruded via a primary na+ pump.the primary extrusion of na+ from mycoplasma gallisepticum cells was demonstrated by showing that when na+-loaded cells were incubated with both glucose (10 mm) and the uncoupler sf6847 (0.4 microm), rapid acidification of the cell interior occurred, resulting in the quenching of acridine orange fluorescence. no acidification was obtained with na+-depleted cells or with cells loaded with either kcl, rbcl, licl, or cscl. acidification was inhibited by dicyclohexylcarbodiimide (50 microm) and diet ...19892526806
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