TitleAbstractYear(sorted descending)
cloacal infection with mycoplasma gallisepticum and the effect of inoculation with h120 infectious bronchitis vaccine virus.infectivity of an isolate of mycoplasma gallisepticum of low virulence was studied in specific pathogen free chickens from 1 day old until after the onset of lay. widespread cloacal infection developed and it was discussed in relation to the low serological response. the effects produced by inoculation of h120 infectious bronchitis vaccine virus and coming into lay were associated with changes in serological response and increased cloacal cultural recovery. the possibility of ascending cloacal i ...198318766808
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
laboratory infection of house sparrows (passer domesticus) with mycoplasma gallisepticum and mycoplasma 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
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
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
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
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
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
[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
application of enzyme-linked immunosorbent assay for detecting antibody to mycoplasma gallisepticum infections in 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
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
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
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
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
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
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
survey of the health and husbandry of small poultry flocks in great 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
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
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
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
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
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
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
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
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
effects of ionophores and dicyclohexylcarbodiimide on mycoplasma gallisepticum adherence 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
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
microagglutination test for the detection of antibodies to mycoplasma gallisepticum and m. synoviae in avian sera. 19827150146
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
the effect of phospholipase a2 on intact cells and isolated membranes of mycoplasma gallisepticum. 19827160381
proton motive force across the membrane of mycoplasma gallisepticum and its possible role in cell volume regulation.a proton motive force (delta (-) microh+) of 70 to 130 mv was measured across the membrane of mycoplasma gallisepticum cells. the membrane potential was measured utilizing the lipid-soluble cation tetraphenylphosphonium. the method was validated by showing that in the presence of valinomycin the ratio of the concentrations (in/out) of tetraphenylphosphonium agreed well with those for k+ and rb+. the ph gradient was calculated from the measured distribution ratio of benzoic acid. the proton motiv ...19817204343
control of membrane lipids in mycoplasma gallisepticum: effect on lipid order.adaptation of mycoplasma gallisepticum, a sterol-requiring mycoplasma sp., to growth in a serum-free medium supplemented with cholesterol in decreasing concentrations and with various saturated or unsaturated fatty acids enabled us to control both the cholesterol levels and the membrane fatty acid composition. an estimate of the membrane physical state from fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene indicated that the membrane lipids of native m. gallisepticum were highly ordered ...19817216998
determination of cholesterol asymmetry by rapid kinetics of filipin-cholesterol association: effect of modification in lipids and proteins.the rapid kinetic behavior of filipin association with cholesterol was unaffected by binding of water-soluble proteins to vesicle and mycoplasma membranes and by proteolytic digestion of mycoplasma membrane proteins. the kinetic properties were, however, dependent on the membrane phospholipids, in that the initial rate of filipin association with cholesterol was enhanced by phospholipase a2 treatment by the incorporation of lysophosphatidylcholine, and by increasing the degree of unsaturation in ...19817236612
the effects of different concentrations of glucose and horse serum on the growth of mycoplasma gallisepticum in broth culture. 19817240266
immunological response of chickens to mycoplasma gallisepticum infection.the cellular, humoral, and local immune responses of chickens to mycoplasma gallisepticum infection were studied at weekly intervals for 10 weeks. a cellular response was indicated by significant leukocyte migration inhibition (lmi) was demonstrated as early as one week postinfection (pi), but the maximum lmi of 36.4% was observed at seven weeks pi. induction of cellular response was further confirmed by positive-delayed type of hypersensitivity reaction, observed in all infected birds tested. t ...19817259674
vaccination with f-strain mycoplasma gallisepticum to reduce production losses in layer chickens.the effect of mycoplasma gallisepticum (mg) infection or vaccination of conn. f-strain mg on 45 weeks of egg production was analyzed using production records from 132 flocks of commercial layer hens. the flocks were located in pennsylvania, and the data were collected for two years. on the average, layers maintained free from infection with mg laid 15.7 more eggs/hen housed than the mg-infected layers; figures were adjusted for layer-strain effect. this adjusted advantage decreased to 8.7 eggs/h ...19817259680
pathogenicity of strains of the ijknqr group of avian mycoplasmas for turkey embryos and poults.strains of mycoplasmas isolated from turkey embryos and identified as belonging to the ijknqr group of avian mycoplasmas were found to produce lethal infections in experimentally exposed turkey embryos. some strains produced exudative airsacculitis in experimentally exposed poults. of 4 strains used to inoculate poults, two produced moderate airsacculitis, one produced a slight airsacculitis, and one had little or no effect on turkey poult air sacs. microscopic examination revealed that the air- ...19817271648
the effects of growth in broth containing different concentrations of glucose and horse serum on mycoplasma gallisepticum rapid serum agglutination antigens. 19817275994
isolation and characterization of mycoplasma and acholeplasma from apparently healthy and diseased (infectious sinusitis) turkeys.investigation of 136 turkeys (24 manifesting infra-orbital sinusitis, 112 apparently healthy) resulted in isolation of 79 strains of mycoplasma and 4 of acholeplasma. by the disc growth inhibition test with 16 reference antisera of avian serogroups, 55 strains were identified serologically and 28 remained unidentified. thirteen strains of mycoplasma gallisepticum, 1 of m. meleagridis, and 2 of acholeplasma laidlawii were isolated from turkey sinusitis whereas serogroups c (2), d (19), f (8), m. ...19817278710
mycoplasma-induced arthritis in poultry.mycoplasmaa-induced arthritis of poultry under field conditions is almost entirely caused by mycoplasm synoviae (ms) infection. experimentally, mycoplasma synoviae, mycoplasma gallisepticum, mycoplasma meleagridis and mycoplasma iowae have all been shown to cause arthritis, tenosynovitis and lesions of periarticular tissue. however, greatest attention has been given to ms in this respect. the leg joints are most consistently involved, and of these particularly the tibiotarsal-tarsometatarsal and ...19817287403
antibiotic sensitivity patterns in field isolates of mycoplasma gallisepticum as a guide to chemotherapy.control of mycoplasma gallisepticum (mg) infection in commercial poultry flocks has sometimes been achieved by the intensive use of antibiotics. in some cases, a single drug, tylosin tartrate, has been used repeatedly in prophylactic and therapeutic applications. it appears that this selective pressure can lead to the emergence of strains with reduced sensitivity to tylosin. this was observed in mg strains isolated in 1978 from turkey breeding flocks repeatedly treated with tylosin, but not in ...19817287408
vaccination of chickens with nonpathogenic mycoplasma gallisepticum as a means for displacement of pathogenic strains.attempts to solve the problem of mycoplasma gallisepticum (mg) infection of poultry by a combination of eradication and antibiotic treatment have at best met with only partial success. as a result of the continuing economic burden of the disease, there has been a renewed interest in vaccination as a tool in the control of mg. a particularly pressing problem exists in the commercial egg industry, where the occurrence of mg infection of layer hens at the onset of egg production leads to a marked d ...19817287410
mycoplasmosis in poultry.mycoplasma gallisepticum, mycoplasma synoviae and mycoplasma meleagridis are the most widespread pathogenic poultry mycoplasmas. the epidemiology of the infections, and clinical signs, lesions, pathogenesis, diagnosis and control of disease are described. in epidemiology, the constant antigenic composition, variation in virulence, tropism, survival of the mycoplasma outside and within the host and susceptibility to drugs are outlined. the significance of species, age and immune status of the hos ...19817287415
light microscopic, scanning electron microscopic, and histomorphometric evaluation of mycoplasma gallisepticum-induced airsacculitis in chickens. 19817294464
sequential pathology of genital tract in chickens experimentally infected with mycoplasma gallisepticum.unsexed day-old white leghorn chicks hatched from eggs pre-treated with erythromycin were infected via the yolk sac with a 48-hr broth culture of pathogenic mycoplasma gallisepticum (s6). fourteen of the 57 experimental female birds had gross lesions in the oviduct, characterized by the presence of grayish-white caseous plugs of various sizes in a segment or throughout the length of the oviduct. forty-six of the infected female birds had microscopic lesions, detected primarily as mild heterophil ...19817316912
symmetrical distribution and rapid transbilayer movement of cholesterol in mycoplasma gallisepticum membranes.the exchange of cholesterol between [14c]cholesterol-labeled mycoplasma gallisepticum cells and an excess of sonicated egg phosphatidylcholine/cholesterol vesicles (molar ratio of 0.9) was measured. more than 90% of the radioactive cholesterol underwent transfer from intact cells to the vesicles. the kinetics of the transfer was biphasic. about 50% of the radioactive cholesterol was exchanged with a half-time of about 4 h. the residual was exchanged at a slower rate with a half-time of about 9 h ...19817317418
transmissibility of the f strain of mycoplasma gallisepticum in leghorn chickens.leghorn pullets free of mycoplasma gallisepticum (mg) were infected with the f strain of mg at approximately 18 weeks of age. at various times up to 27 weeks postinfection, infected chickens were placed in a pen with uninfected controls. infected chickens remained tracheal carriers up to 49 weeks postinfection. infection was readily transmitted to penmates during the first 4 weeks postinfection; in most instances from 6 through 27 weeks postinfection, transmission to penmates became progressivel ...19817337604
a mycoplasma gallisepticum epornitic in turkeys: its epidemiology and eradication. 19817337605
immunogenic potency of oil-emulsified mycoplasma gallisepticum bacterins.immunogenicity of an aqueous mycoplasma gallisepticum (mg) bacterin and two oil-emulsified bacterins with aqueous-phase-to-oil-phase ratios of 1:2 and 1:4 were evaluated in 3 groups of 5-week-old mg-free white leghorn chickens. group 4 chickens were nonimmunized controls. group 1, 2, and 3 chickens received primary immunizations with 0.5 ml of bacterin subcutaneously (sc). six weeks later, half of the vaccinated chickens received a second immunization (0.5 ml sc). six weeks after the last dose o ...19817337609
characterization of an isolate of mycoplasma wvu 907 which possesses common antigens to mycoplasma gallisepticum.antigenic characteristics of an isolate of mycoplasma wvu 907 were compared with mycoplasma gallisepticum (mg) and mycoplasma synoviae. mycoplasma wvu 907 and mg share common agglutinating and precipitin antigens. although hemagglutinin is an integral part of wvu 907, hemagglutinating-inhibited antibody was not detected in sera of chickens inoculated with wvu 907. the clinical symptoms observed in chickens inoculated with wvu 907 were mild. viral infections of chickens helped spread wvu 907 to c ...19817337614
[microscopic and ultramicroscopic lesions from experimental mycoplasma infection in respiratory tract of chickens. possible difference between pathogenic and non pathogenic strains (author's transl)].for three weeks after experimental infection of trachea and scroll bone with mycoplasma gallisepticum no lesions were detected in scroll bone, but only an abundant mucous secretion. mycoplasmas were present and adhered to cilia of epithelial cells. in trachea an almost complete destruction of cilia was observed allowing swollen epithelial cells to appear with mycoplasmas adhering to villi. strain w31 serotype c caused no lesions but cells and cilia were covered with a thick layer of mucous.19817342836
inactivation of mycoplasmas by long-chain 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
attachment of killed mycoplasma gallisepticum cells and membranes 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
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
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
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
performance of 3 successive generations of specified-pathogenfree chickens maintained as a closed 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
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
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
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
[in vitro susceptibility of mycoplasma gallisepticum field strains to tiamulin and tylosin (author's transl)]. 19806995088
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
[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
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
ultrastructural study of the interaction between acholeplasma laidlawii and antibody.the ultrastructure of agar-grown acholeplasma laidlawii incubated with specific antiserum or igm fractions of this antiserum has been investigated by the thin-sectioning technique. antiserum treatment resulted in the development of giant cells along the colony circumferences and in the coating of normal-size mycoplasmas with a periodically arranged extramembranous layer, consisting of attached immunoglobulins as shown by indirect immunoferritin labelling. the regular structure of the coat was no ...19807373282
the growth and cilia-stopping effect of mycoplasma gallisepticum 1rf in chicken tracheal organ cultures.the growth and pathogenicity of mycoplasma gallisepticum 1rf were studied in chicken tracheal organ cultures. the organism propagated only in the presence of tracheal rings in culture fluids. presence of metabolic products from rings seems to be an important factor for the growth of organism. production of hydrogen peroxide was not detected. there were no differences in the growth and cilia-stopping effects among organisms maintained in vitro, stored at -18 degrees c, and recovered from air sac, ...19807375737
a survey of mycoplasma infections in domestic poultry.a survey of mycoplasma infections of chickens, turkeys and ducks was made on tissues from a variety of sources and birds of various ages, and from pipped and dead-in-shell turkey embryos. the tissues examined consisted mainly of respiratory tissue and the cloaca and contents and also a small number of joint lesions and other tissues. from chickens, mycoplasmas were isolated from a total of 138 tissues with mycoplasma gallisepticum in preponderance. this was followed by m gallinarum, untyped orga ...19807375739
effect of sex and mycoplasma synoviae infection on chicken red blood cells used for hemagglutination-inhibition test.a total of 10 male and 10 female 9-week-old commercial mycoplasma-free broiler chickens was used in this test. five males and 5 females were artificially infected by aerosol with a broth culture of mycoplasma synoviae (ms) f10-2as. the other 5 males and 5 females were used as noninfected controls. at 3, 9, and 12 weeks postinfection all birds were bled, and the blood was pooled into 4 groups: infected male, noninfected male, infected female, and noninfected female. hemagglutination-inhibition (h ...19807393863
development of a microtitration complement-fixation test for diagnosis of mycoplasma gallisepticum infection in chickens.a direct microtitration complement-fixation (cf) test was developed for diagnosis of mycoplasma gallisepticum infection in chickens. cf titers were demonstrated three weeks postinoculation in chickens inoculated intratracheally with m. gallisepticum. the direct microtitration cf test appeared comparable to the hemagglutination-inhibition test in sensitivity and specificity. addition of fresh chicken serum to lyophilized guinea pig complement (gpc') was not necessary to enhance fixaton of gpc' by ...19807436960
preliminary clinical pharmacological investigations of tylosin and tiamulin in chickens.the minimal inhibitory concentrations (mic) of tiamulin and tylosin for mycoplasma, gram-positive, and gram-negative micro-organisms isolated from chickens were determinated by the agar dilution method. median mic values for tiamulin against mycoplasma gallisepticum (0.05 microgram/ml) and mycoplasma synoviae (0.10 microgram/ml) were 2 to 4 times lower than the corresponding values for tylosin. tiamulin was also slightly more effective in vitro in inhibiting escherichia coli, pasteurella multoci ...19807444918
comparison of mycoplasma synoviae hemagglutinating antigens by the hemagglutination-inhibition test.mycoplasma synoviae (ms) strains were isolated from the trachea of hens from ms-positive broiler breeder flocks having progeny condemnations due to airsacculitis. hemagglutinating (ha) antigens were made from several strains. the ha antigen made from the 95th medium passage of ms fmt strain was compared with that of the standard ms wvu 1853 strain by the hemagglutination-inhibition (hi) test. sixty-six sera from 10 ms-positive flocks, 4 mycoplasma gallisepticum (mg)-positive sera, and 7 normal s ...19807447835
[effect of selected solvents on mycoplasma gallisepticum]. 19807456534
evaluation of a vaccine against mycoplasma gallisepticum in commercial broilers.the efficacy of live mycoplasma gallisepticum (mg) vaccine against respiratory mycoplasmosis was studied in three laboratory trials with commercial broilers. broiler chickens were infected with the f or r strain of mg by eyedrop at 1 day of age, and challenged by aerosol exposure to the r strain of mg along with eyedrop vaccination against newcastle disease and infectious bronchitis at 30 or 34 days of age. observations were made of macroscopic lesions, severity of airsacculitis, isolations of m ...19807271643
preliminary clinical pharmacological investigations of tylosin and tiamulin in chickens.summary the minimal inhibitory concentrations (m1c) of tiamulin and tylosin for mycoplasma. gram-positive, and gram-negative micro-organisms isolated from chickens were determinated by the agar dilution method. median m1c values for tiamulin against mycoplasma gallisepticum (0.05 µg/ml) and mycoplasma synoviae (0.10 µg/ml) were 2 to 4 times lower than the corresponding values for tylosin. tiamulin was also slightly more effective in vitro in inhibiting escherichia coli, pasteurella multocida, ...198022039981
egg production in relation to the results of a long term serological survey of 73 flocks of fowl.summary seventy-three flocks of fowl were tested at regular intervals for the presence of precipitins to fowl adenovirus (av) and infectious bronchitis virus (ibv), haem-agglutinating inhibiting antibodies to bc14 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 bci4 virus reactors and av reactors. in flocks showing p ...198022039854
haemadsorption inhibition test for the identification of mycoplasma gallisepticum and mycoplasma synoviae.summary colonies of the avian mycoplasma strains mycoplasma gallisepticum s6 and mycoplasma synoviae wvu 1853 and two mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. three mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. the haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. no cross-inhibition ...197922039774
the response of the harderian gland of the fowl to antigen given by the ocular route. ii. antibody production.after ocular administration to young chickens of sheep erythrocytes (srbc), newcastle disease virus (ndv), infectious bronchitis virus (ibv) or mycoplasma gallisepticum, homologous antibody was detected in serum and in saline extracts of harderian glands. parenteral immunisation with srbc or ndv stimulated moderately high serum antibody titres but did not evoke a measurable antibody response by the harderian gland.197918770464
adherence of mycoplasma gallisepticum to glass.attachment of washed mycoplasma gallisepticum cells to glass was quantified with organisms in which membrane lipids were labelled with 3h. siliconization of the test tubes decreased attachment, while centrifugation increased it. attachment increased with temperature, decreased with increasing ph and ionic strength of the attachment mixture, but was unaffected by ca2+, mg2+ and edta. this suggests that ionic bonds, but not salt bridges, participate in the attachment process. glycophorin, the majo ...197937284
immunoprecipitation of triton x-100-solubilized mycoplasma mycoides proteins.mycoplasma mycoides subsp. mycoides (pg1 and strain y) proteins were solubilized in triton x-100, and the antigenic proteins were precipitated from this complex mixture by addition of antiserum and then separated by two-dimensional gel electrophoresis. of the 300 proteins solubilized, about 10 were precipitated. proteins of pg1, a slow-growing, small colony (sc) strain, were precipitated by antiserum to pg1 and by antiserum to strain y, a fast-growing, large colony (lc) strain. similarly, strain ...197993614
electron microscopical study of antibody binding to mycoplasma gallisepticum: indirect immunoferritin labelling.the ultrastructural aspects of the interaction of mycoplasma gallisepticum with specific rabbit antibody have been studied. in particular, fixation conditions which allow the simultaneous preservation of cellular fine structure and membrane antigenicity have been established and applied in a procedure of indirect immunological labelling of the antibody-coated organisms with ferritin conjugated sheep anti-rabbit igg. the advantages of working with agar embedded organisms in a multistep labelling ...1979433599
isolation and identification of avian mycoplasmas in singapore.two hundred and forty batches of chickens with chronic respiratory syndrome were tested for mycoplasmas. one hundred and five batches (43.8%) were found to have mycoplasmosis. a total of 110 isolates of mycoplasma was cultured, of which nine isolates were identified as mycoplasma gallisepticum, 48 avian sero-group d, 45 m. gallinarum, one m. iners and seven unclassified. 2. identification of the mycoplasmas isolated was carried out by biochemical and serological tests (disc growth inhibition and ...1979455110
membrane lipids of mycoplasma gallisepticum: a disaturated phosphatidylcholine and a phosphatidylglycerol with an unusual positional distribution of fatty acids. 1979465448
effects of feeding tylosin to layers exposed to mycoplasma gallisepitcum.two experiments are reported in which the effect of tylosin upon the development of mycoplasma gallisepticum (mg) infection in replacement layers was monitored by serological and cultural methods. concentrations of tylosin tested included 0, 22, 38.5, and 55 ppm. egg production and feed consumption data were collected for one year. tylosin slowed the rate of spread of mg infection as measured by serological and cultural methods. the effect of tylosin on the spread of mg infection was dose relate ...1979471896
haemadsorption inhibition test for the identification of mycoplasma gallisepticum and mycoplasma synoviae.colonies of the avian mycoplasma strains mycoplasma gallisepticum s6 and mycoplasma synoviae wvu 1853 and two mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. three mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. the haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. no cross-inhibition was obser ...1979473153
an ultrastructural study on the interaction of mycoplasma gallisepticum with the chicken tracheal chickens wee intratracheally inoculated with mycoplasma gallisepticum. the tracheas collected 6 and 14 days after chickens were inoculated were subjected to titration of mycoplasma and examination by light and electron microscopy. the mycoplasma organisms grew well; 10(7) to 10(8) color-changing units in a milligram of tissue were determined. tracheal lesions occurred in close association with the presence of mycoplasmas and were characterized by degeneration of the epithelial cell ...1979507485
adaptation of chickens to their handler, and experimental results.chickens were adapted to their handler before the experiment. adapted birds produced more antibody, had more blood protein, gained more weight, and were more resistant to mycoplasma gallisepticum than unadapted birds. the antibody response to sheep red blood cells was not reduced for fasting for 48 hours in adapted birds but was in unadapted birds. differences in antibody titers, blood protein, and weight gains between controls and birds fed 80 ppm of deoxycorticosterone could be demonstrated on ...1979526204
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