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in vitro activity of tiamulin against porcine mycoplasmas.the activity of tiamulin against mycoplasma hyopneumoniae, m flocculare, m hyorhinis and m hyosynoviae grown in liquid medium was assessed in vitro. with the first three of these mycoplasmas, the activity of tylosin and oxytetracycline was observed in parallel. tiamulin was more active against m hyopneumoniae and m flocculare, but there was less disparity between the three antibiotics with the strain of m hyorhinis tested. tiamulin was notably more active against m hyosynoviae than against m hyo ...19853975477
eradication of some infectious pig diseases by perinatal tiamulin treatment and early weaning.from 10 days before the expected date of farrowing onwards, 97 sows infected by mycoplasma hyopneumoniae and treponema hyodysenteriae were given tiamulin daily at a dosage of 20 mg/kg bodyweight via the feed. three days before farrowing the sows were washed with a disinfectant and transferred to an isolated farrowing house. the sucking piglets remained with their dams for five days, during which time the sows continued to receive the tiamulin-containing feed. the sucking piglets also received ti ...19853984171
isolation of a cytopathic factor from mycoplasma hyopneumoniae.a cytopathic factor was isolated from m. hyopneumoniae vpp11 membranes. this factor had an isoelectric point of 6.2 and was capable of inducing cytopathic effect in mrc-5 human lung fibroblast culture at a concentration of 250 ng of protein per ml. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of this cytopathic factor showed a major band with a molecular weight of approximately 54,000.19853988348
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
microorganisms associated with pneumonia in slaughter weight swine.the lungs of 334 pigs were obtained from two slaughter plants in minnesota and examined in detail. macroscopic and microscopic evaluation, direct fluorescence for mycoplasma hyopneumoniae and bacterial culture were done on all of them and a subsample of 50 were selected for virus culture. mycoplasma hyopneumoniae, pasteurella multocida and haemophilus spp. were detected in 24.0%, 34.1% and 27.0% of the lungs, commonly in conjunction with each other. one isolate of haemophilus pleuropneumoniae se ...19854016578
apparent reinfection of enzootic-pneumonia-free pig herds: search for possible causes.in a control scheme for enzootic-pneumonia-free herds, run by the pig health control association, a detailed study was made of 55 herds that developed enzootic pneumonia without a simple explanation. these herds were compared with 57 herds that were still free from enzootic pneumonia in mid-1984. a high standard of precautions against the risk of infection being transferred by people and fomites seemed to confer no obvious benefit. this observation was in keeping with in vitro studies which show ...19854024433
[respiratory diseases of swine: some epidemiologic aspects].epidemiological surveys enable to know better the aetiology of respiratory diseases. the surveys carried out in slaughter-houses in brittany (france) in 1980 and 1981, show a worrying situation concerning porcine respiratory diseases. microbiological studies brought out the preponderance of the isolation of mycoplasma hyopneumoniae, pasteurella multocida, bordetella bronchiseptica, streptococcus suis and actinobacillus suis. some patterns of experimental infection with mycoplasma hyopneumoniae a ...19854064626
suppressive effect of nonviable mycoplasma hyopneumoniae on phytohemagglutinin-induced transformation of swine lymphocytes.the effect of nonviable mycoplasma hyopneumoniae on transformation of swine peripheral blood lymphocytes by mitogen was investigated. lymphocyte transformation was evaluated as incorporation of [3h]-thymidine, using a microculture system. mycoplasma hyopneumoniae was grown in friis medium, inactivated with sodium azide, and washed with phosphate-buffered saline solution. four strains of m hyopneumoniae, strain j, strain 11, and 2 low-passage isolates (1361a, 1375c), were found to suppress phytoh ...19854073648
the occurrence of mycoplasmas in the lungs of pigs in new zealand.attempts were made to recover and serologically identify mycoplasmas from the lungs of 50 pigs with mycoplasmal pneumonia and from 50 lungs without gross evidence of pneumonia. mycoplasma hyopneumoniae and m. hyorhinis were respectively cultured from 30% and 50% of pneumonic lungs and the former species was also recovered from 12% of non-pneumonic lungs. three other isolates (one from pneumonic and two from non-pneumonic lungs) differed in colonial morphology from m. hyopneumoniae and m. hyorhin ...198516031118
the synergistic activity of tiamulin and chlortetracycline: in-feed treatment of bacterially complicated enzootic pneumonia in fattening pigs.the antibacterial effects of a combination of tiamulin and chlortetracycline in vitro against a number of field isolates of pasteurella multocida, haemophilus pleuropneumoniae and bordetella bronchiseptica were examined. there was a marked synergism between the two antibiotics against all eight isolates of p multocida, against seven of nine isolates of h pleuropneumoniae and against the single strain of b bronchiseptica tested. two field trials were carried out on a herd with a history of compli ...19863750792
serological control of spf and conventional swine herds for mycoplasma hyopneumoniae infection. 19862938556
studies on the phospholipid composition of pathogenic cell membranes of mycoplasma hyopneumoniae.the membrane phospholipid and fatty acid compositions of mycoplasma hyopneumoniae, a pathogen of porcine enzootic pneumoniae isolated in china, was studied by thin-layer chromatography and gas chromatography. the results showed that membrane phospholipids consisted predominantly of diphosphatidylglycerol. the percentage of c16 - c18 fatty acids comprised 79% of the total fatty acids, of which oleic acid as well as palmitic acid are the major fatty acids. some differences were shown in fatty acid ...19863943616
in vitro susceptibility of mycoplasma hyopneumoniae to antibiotics. 19863959363
experiences from eradication of mycoplasma hyopneumoniae infection by tiamulin treatment. 19863964005
analysis of transcription and processing signals of the 16s-23s rrna operon of mycoplasma hyopneumoniae.the 16s and 23s rrna genes of mycoplasma hyopneumoniae are closely spaced in one operon. the two genes are separated by a spacer region of 500 bp which shows no sequence homology to bacterial trna genes. within this operon seven 5' and five 3' ends of various rrna species were mapped and the corresponding dna was sequenced. the results are consistent with the following model for synthesis of rrnas: transcription of the operon is initiated from either of two tandemly arranged promoters leading to ...19863470591
organization of the ribosomal rna genes in mycoplasma hyopneumoniae: the 5s rrna gene is separated from the 16s and 23s rrna genes.in order to study the organization of the ribosomal rna genes of mycoplasma hyopneumoniae the rrna genes were cloned in phage vectors lambda embl3 and lambda embl4. by subcloning the restriction fragments into various plasmids and analysing the resulting clones by southern and northern blot hybridization, a restriction map of the rrna genes was generated and the organization of the rrna genes was determined. the results show that the genes for the 16s and 23s rrnas are closely spaced and occur o ...19863550383
in vitro antibacterial properties of el-870, a new semi-synthetic macrolide antibiotic.a new macrolide antibiotic, el-870, 20-deoxo-20-(3,5-dimethylpiperidin-1-yl)desmycosin, has been prepared by chemical modification of desmycosin. in vitro, against selected animal bacterial pathogens, it inhibited growth of pasteurella multocida, pasteurella haemolytica, mycoplasma hyopneumoniae, actinobacillus pleuropneumoniae, streptococcus suis, actinomyces pyogenes and certain other bacteria at levels of 6.25 micrograms/ml or less. in general, the mics for gram-negative enteric bacteria have ...19873570967
comparison of enzyme-linked immunosorbent assay (elisa) and indirect hemagglutination (iha) in experimental mycoplasma hyopneumoniae infection of pigs.twenty-five hysterectomy-derived piglets were infected intratracheally at 16 days of age with a field strain of mycoplasma hyopneumoniae. twenty uninfected piglets constituted the control group. clinical symptoms were noted daily and sera collected weekly. the 45 pigs were killed from 1 to 20 weeks after infection. m. hyopneumoniae induced a temperature response, coughing and pneumonia. after 10 weeks, a noticeable regression of the macroscopic lung lesions was observed. the infection was follow ...19873667230
early serological responses to mycoplasma hyopneumoniae infection.a complement fixation (cf) test for mycoplasma hyopneumoniae antibody, using the complement dilution method, will detect infection in inoculated pigs at an early stage. the interval between inoculation and the first positive cf response--defined as 4.6 u of complement fixed--was determined for four separate methods of inoculation and for pigs with artificially induced pneumonia. sera from two groups were tested by the enzyme-linked immunosorbent assay (elisa). by cf, the i.v. group showed positi ...19873667231
cross-reactions between mycoplasma hyopneumoniae and mycoplasma flocculare--practical implications for the serodiagnosis of mycoplasmal pneumonia of swine.previous studies using hyperimmune antisera revealed significant serologic cross-reactions between mycoplasma hyopneumoniae and m. flocculare. these findings, coupled with observations that m. flocculare infection may be widespread, indicated that antibodies to m. flocculare might be common in swine sera and thus cause nonspecific reactions in serodiagnostic tests for mycoplasmal pneumonia of swine (mps). information reported here indicates that this premise may be invalid. twenty-one swine were ...19873667232
use of monoclonal antibody in an enzyme-linked immunosorbent assay (elisa) for the detection of antibodies against mycoplasma hyopneumoniae.a double-sandwich elisa using monoclonal antibody (mcab) has been developed for the detection of swine antibodies against mycoplasma hyopneumoniae. mcab recognizing a 46-kilodalton (kda) component of m. hyopneumoniae was employed for coating polystyrene microplate wells. in a comparison, the double-sandwich elisa and complement fixation (cf) test antibodies were detected at almost the same time by both methods; however, elisa antibodies persisted for a longer period than those detected by the cf ...19873667233
major membrane surface proteins of mycoplasma hyopneumoniae selectively modified by covalently bound lipid.surface protein antigens of mycoplasma hyopneumoniae were identified by direct antibody-surface binding or by radioimmunoprecipitation of surface 125i-labeled proteins with a series of monoclonal antibodies (mabs). surface proteins p70, p65, p50, and p44 were shown to be integral membrane components by selective partitioning into the hydrophobic phase during triton x-114 (tx-114)-phase fractionation, whereas p41 was concomitantly identified as a surface protein exclusively partitioning into the ...19873680170
assessment of antibody response of swine infected with mycoplasma hyopneumoniae by immunoblotting.an immunoblot procedure was used to evaluate porcine antibody response to inoculation with mycoplasma hyopneumoniae. mycoplasmas solubilized with sodium dodecyl sulfate were used as antigens. antibodies to 5 antigens, estimated to be of molecular weight (mol wt) 110,000, 64,000, 50,000, 41,000, and 36,000, were detected in sera collected during the course of induced mycoplasmal pneumonia. mycoplasma hyopneumoniae antigens, mol wt 110,000, 50,000, 41,000, and 36,000, cross-reacted with m floccula ...19873296884
v-factor dependent strains of pasteurella multocida subsp. multocida.at bacteriological examination of swine lungs with pneumoniae due to mycoplasma hyopneumoniae, two strains of pyridine nucleotide (v-factor) requiring bacteria were isolated. they exhibited a pattern of biochemical reactions fitting with that of pasteurella multocida subsp. multocida. deoxyribonucleic acid (dna): dna hybridization with these isolates and pasteurella multocida subsp. multocida showed that they were v-factor requiring strains of this species. preliminary investigations on the qual ...19873425031
the mycoplasma hyopneumoniae plasma membrane as a vaccine against porcine enzootic pneumonia.from an economical standpoint, the colonization of the respiratory epithelium by mycoplasma hyopneumoniae, the mollicute responsible for enzootic pneumonia in pigs which leads to a reduction in the weight gain/feed ratio, has serious consequences in very young animals; we show here that its is possible to efficiently protect these animals with the colostral antibodies raised in sows immunized during their gestation with m. hyopneumoniae bq14 membranes. in an experiments using 9 sows and 75 pigle ...19873440060
nucleotide sequence of the 16s rrna of mycoplasma hyopneumoniae. 19872438659
gene expression signals in mycoplasma hyopneumoniae and mycoplasma capricolum.in mycoplasma hyopneumoniae, the single genes for 16s and 23s rrnas are clustered in one operon from which the 5s rrna gene is separated by more than 4 kbp. this operon, gene 2413 and gene x from m. hyopneumoniae and the 5' ends of both rrna operons from m. capricolum were cloned and used for analysis of the following gene expression signals: promoters and terminators of the dna-directed rna polymerase, ribosomal binding sites of mrna, and sites for processing of precursor rrna. the analyses wer ...19872444558
identification of intrinsic and extrinsic membrane proteins bearing surface epitopes of mycoplasma hyopneumoniae.a library of monoclonal antibodies (mcabs) raised against mycoplasma hyopneumoniae was screened to select mcabs that bound both to surface epitopes on intact organisms and to corresponding proteins identified by immunoblot analysis. four proteins (indicated by mw in kilodaltons) were established as surface antigens: p65, p50, p44 and p41. triton x-114 detergent phase fractionation of whole organisms clearly distinguished p65, p50 and p44 as hydrophobic integral membrane proteins, whereas p41 was ...19872444562
reiterated dna sequences defining genomic diversity within the species mycoplasma hyorhinis.genomic restriction fragments isolated from mycoplasma hyorhinis and mycoplasma hyopneumoniae were shown by dna hybridization and nucleotide sequence analyses to contain sequences common to these two species, as well as another porcine-derived mycoplasma, mycoplasma flocculare. intraspecies hybridization experiments using these fragments as probes indicated that the sequence is highly redundant in several strains of m. hyorhinis, but that there is diversity in the sizes of restriction fragments ...19882460718
[influenza in piglets, back again?].a diagnosis of mycoplasma hyopneumoniae infection in coughing piglets was verified using an elisa technique by the animal health service of the province of limburg, the netherlands.19883341005
a cox regression analysis of risk factors related to mycoplasma suipneumoniae reinfection in danish spf-herds. 19882976576
identification of mycoplasma hyopneumoniae in formalin-fixed porcine lung, using an indirect immunoperoxidase method.an indirect immunoperoxidase staining technique was evaluated for detection of mycoplasma hyopneumoniae in formalin-fixed, paraffin-embedded porcine lung. lungs from swine with induced (n = 4) or naturally occurring m hyopneumoniae infection (n = 31) were examined grossly, by light and immunofluorescent microscopy, and by an indirect immunoperoxidase test, using antibody raised in swine against m hyopneumoniae as the primary antibody. organisms stained by the indirect immunoperoxidase method wer ...19883056138
antimycoplasmal activities of the pseudomonic acids and structure-activity relationships of monic acid a derivatives.the antimycoplasmal activities of the pseudomonic acids isolated from pseudomonas fluorescens ncib 10586 are reported. structure-activity relationships of a variety of ester, amide and thiol ester derivatives of the nucleus, monic acid a, are described. enhanced antimycoplasmal activity is reported for a number of monic acid a esters and the most potent derivative, m-nitrobenzyl monate a, is a 100-fold more active against mycoplasma hyopneumoniae than pseudomonic acid a.19883133344
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
evaluation of tiamulin for treatment of mycoplasmal pneumonia in swine.during 3 trials, using affected pigs of various ages, tiamulin was evaluated for treatment of experimentally induced mycoplasmal pneumonia. pneumonia was induced in respiratory tract disease-free swine by intratracheal inoculation of a lung homogenate containing mycoplasma hyopneumoniae. eleven days after inoculation, when more than 20% of pigs were coughing, pigs were allotted to 3 or 4 groups (n = 8 pigs each) and were given regimens of no medication or 60 mg, 120 mg, or 180 mg of tiamulin/l o ...19883170319
mycoplasma hyopneumoniae increases the susceptibility of pigs to experimental pasteurella multocida pneumonia.the interaction between mycoplasma hyopneumoniae and pasteurella multocida in experimental pneumonia was investigated in conventional pigs. the experimental animals were 49 days old when inoculated with m. hyopneumoniae; they were inoculated with p. multocida after 23 days, and killed 13 days later. in pigs inoculated only with p. multocida, clinical signs and lung lesions were not observed, and the agent was not recovered. pigs inoculated with m. hyopneumoniae developed fever, moderate cough an ...19883196973
immunoblotting analysis of antibody response in swine experimentally inoculated with mycoplasma hyopneumoniae.serological cross-reactivity among swine mycoplasmas, and porcine antibody response to mycoplasma hyopneumoniae antigens during experimental infection were investigated by enzyme-linked immunosorbent assay (elisa) and the immunoblotting technique. mycoplasmas solubilized with tween 20 were used as antigen. cross-reactivity between m. hyopneumoniae and m. flocculare was indicated by elisa and it was demonstrated by immunoblotting, which revealed that the predominant cross-reactive antigens were c ...19883252616
[fluorescence serological and culture detection of mycoplasma hyopneumoniae and mycoplasma hyorhinis in swine lungs].the present paper compares the fluorescence-serological detection of m. hyopneumoniae and m. hyorhinis in frozen sections with cultural procedures. in 161 lungs of swine the agent of enzootic pneumonia, m. hyopneumoniae, was found almost exclusively in frozen sections (22 times). only one strain was cultivable. m. hyorhinis was detected 59 times by culture but only 18 times in the sections. for the detection of m. hyopneumoniae therefore the fluorescence-serological investigation of lung section ...19892647076
in vitro evaluation of various quinolone antibacterial agents against veterinary mycoplasmas and porcine respiratory bacterial pathogens.the in vitro activities of 12 quinolones and four antibiotics were determined against 15 veterinary mycoplasmal species and four species of bacteria commonly involved in respiratory infections in pigs. the newer quinolones were markedly more active in vitro against a wide range of mycoplasmas than nalidixic acid and the earlier quinolones. against mycoplasma hyopneumoniae ciprofloxacin was the most active quinolone with a geometric mean minimal inhibitory concentration (mic) against 16 strains o ...19892704885
hemagglutination and hemagglutination inhibition of turkey red blood cells with mycoplasma hyopneumoniae.the ability of mycoplasma hyopneumoniae to agglutinate rbc was evaluated to develop an in vitro cytadsorption assay. using swine rbc in a microtitration hemagglutination test, no agglutination or partial agglutination was detected. comparison of rbc from various other species indicated that improved hemagglutination was obtained with rbc from turkeys. this hemagglutination was detected only when mycoplasma cells used in the assay had been frozen and thawed, heated at 50 c for 30 minutes, or trea ...19892774322
a gene probe to detect mycoplasma hyopneumoniae, the etiological agent of enzootic porcine pneumonia.enzootic porcine pneumonia is caused by mycoplasma hyopneumoniae. since the disease is of world-wide importance it is important to detect and identify the causative agent. in experience laboratories this mycoplasma can usually be detected by culture but its identification still is difficult and time consuming. we have cloned random eco r1 fragments of m. hyopneumoniae dna to m13mp19 and used the resultant recombinant to produce a probe capable of detecting approximately 10 pg of the mycoplasma d ...19892797007
protection against enzootic pneumonia of pigs: intraperitoneal inoculation with live lkr strain of mycoplasma hyopneumoniae.pigs obtained from a mycoplasma-free piggery were randomised into 4 groups of 9. groups 1 and 2 were injected by the intraperitoneal route with liquid culture of the lkr strain of mycoplasma hyopneumoniae. group 1 was injected once and group 2 twice. group 3 was made up of pigs inoculated by the intranasal route with the virulent beaufort strain of m. hyopneumoniae; they served as the source of infection for the challenge. group 4 were uninfected, uninjected controls. six weeks after the last in ...19892930394
preparation of mycoplasma hyopneumoniae antigen for the enzyme-linked immunosorbent assay.methods of preparation of mycoplasma hyopneumoniae antigens for the enzyme-linked immunosorbent assay to detect specific antibody, and properties of the antigens, are described. the reactivity and specificity of antigen prepared by sephacryl s-300 column chromatography after treatment of m. hyopneumoniae cells with tween 20 (s-300 antigen) were superior to those of antigen prepared by sephadex g-25 column chromatography after treatment with tween 20, or to lipid antigen. there were no difference ...19892523756
[the influence of previous infections on the development of experimental swine pleuropneumonia in specific pathogen free pigs].this study was designed to determine in six-week old specific pathogen free pigs, the effect of previous experimental exposure to mycoplasma hyopneumoniae and transmissible gastroenteritis virus on a challenge infection with actinobacillus pleuropneumoniae. pigs exposed simultaneously to m. hyopneumoniae and transmissible gastroenteritis virus appeared more resistant to challenge (one week later) with a. pleuropneumoniae. four pigs out of a group of ten died following the challenge infection, co ...19892531628
[pathologic consequences of a severe influenza outbreak (swine virus a/h1n1) under natural conditions in the non-immune sow at the beginning of pregnancy].pathological consequences of a severe outbreak of swine influenza (h1n1 virus) in the non immune sow at the beginning of pregnancy, under natural conditions. a sudden acute outbreak of fever, depression, anorexia and coughing in a group of nulliparous sows from a herd that was currently under epidemiological investigation lead to build a particular disposal of observation. the clinical signs were daily recorded including rectal temperature. blood was taken from the sows at the beginning of the t ...19892550169
a mycoplasma genetic element resembling prokaryotic insertion sequences.nucleotide sequence analysis of two mycoplasma hyopneumoniae-derived copies of a repetitive genetic element revealed structural similarities to typical prokaryotic insertion sequences. this is the first such sequence identified in the class mollicutes. the element spans approximately 1550bp, with 28bp inverted terminal repeats. two open reading frames occur within the sequence, one potentially encoding a protein with a size-variant alpha-helical domain containing heptameric leucine periodicity. ...19892552257
enzootic pneumonia in feeder pigs: observations on causal factors.a number of factors were studied in eight feeder pig herds, affected with severe or mild enzootic pneumonia, in order to identify those associated with this disease. piggeries with poor facilities and management and where procurement of piglets was from sales barns were more severely affected with enzootic pneumonia than were those with good facilities and where pigs originated directly from breeding units. serological tests and virus isolation revealed that all herds had been exposed to mycopla ...198917423261
enzootic pneumonia in feeder pigs: association with transmissible gastroenteritis virus infection.infection with transmissible gastroenteritis virus (tgev) was present in some pigs on arrival at a feeder pig farm and was well established three weeks later. tge infection preceded mycoplasma hyopneumoniae infection, which was not detected until three weeks after arrival. severe lesions of enzootic pneumonia were observed at the end of the fattening period.a trial was subsequently done in six-week-old-pigs in order to evaluate the potentiating effect of tgev infection on experimental m. hyopneu ...198917423290
evaluation of the elisa and comparison to the complement fixation test and radial immunodiffusion enzyme assay for detection of antibodies against mycoplasma hyopneumoniae in swine serum.an enzyme-linked immunosorbent assay (elisa) was evaluated for detection of antibodies (ab) against mycoplasma hyopneumoniae and m. flocculare in sera from swine experimentally infected with these agents. in addition, the elisa was compared with the complement fixation test (cft), and radial immunodiffusion enzyme assay (ridea) for the demonstration of ab against m. hyopneumoniae. twenty two 6-week-old swine from a respiratory disease-free herd were divided into five groups. two or three pigs fr ...19902126409
effect of growth in cell cultures and strain on virulence of mycoplasma hyopneumoniae for swine.in an attempt to develop better methods for consistent induction of pneumonia in naturally born swine, using cultures of mycoplasma hyopneumoniae, fifty 6-week-old, naturally born pigs from a respiratory disease-free herd were used in 3 trials. pigs inoculated with mycoplasma hyopneumoniae strain 232 (passage 21) grown for 1 passage or 5 passages in eagle minimal essential medium plus 20% porcine serum, with or without human lung fibroblasts, had a mean (+/- sd) value range between 5.4 +/- 3.6 a ...19902180349
serum antibody response to mycoplasma hyopneumoniae measured by enzyme-linked immunosorbent assay after experimental and natural infection of pigs.studies were conducted under experimental and field conditions to determine the effect of infection with m. hyopneumoniae on the immune response in serum as measured by elisa. following intratracheal challenge or contact exposure, serologically negative pigs derived from mycoplasma-free piggeries developed an immune response within 10 days. this response continued to rise for a further 50 days. in a field study in a commercial piggery, no animals (0/44) were observed to have m. hyopneumoniae ant ...19902188644
treatment of experimental enzootic pneumonia of the pig by norfloxacin or its 6-chloro analogue.the 6-chloro analogue of norfloxacin (compound a) administered continuously in the feed at 400 ppm for 21 days markedly reduced the extent and activity of pneumonic lesions in pigs with pneumonia induced experimentally with an homogenate of pneumonic lung and broth cultures of mycoplasma hyopneumoniae. norfloxacin at 100 ppm or compound a at 200 ppm in the feed did not reduce the extent of lung lesions, although half the pigs treated with norfloxacin had lesions which appeared histologically to ...19902236918
the growth response of mycoplasma hyopneumoniae and mycoplasma flocculare based upon atp-dependent luminometry.cultures of mycoplasma hyopneumoniae and m. flocculare in friis' broth grew faster and to higher titers in air than in 8% co2; cultures in air grew better when shaken than when stationary. under the optimal conditions, both species have generation times of about 10 h and achieve maximum titers of at least 10(9) organisms per ml. maximum growth was reached near ph 7.0, before the phenol red indicator had noticeably changed colour. changes in growth were readily detected by an atp assay based upon ...19902238459
effects of mycoplasma hyopneumoniae and actinobacillus (haemophilus) pleuropneumoniae infections on alveolar macrophage functions in swine.alveolar macrophages were collected at necropsy from pigs inoculated with mycoplasma hyopneumoniae or actinobacillus pleuropneumoniae or both and were tested for phagocytic capabilities, using in vitro techniques. macrophages from noninoculated littermates were used as controls. alveolar macrophages from pigs inoculated with either m hyopneumoniae or a pleuropneumoniae had significantly (p less than 0.05 to p less than 0.0025) higher phagocytic capacity than that of noninoculated controls. macro ...19902301832
adherence of mycoplasma hyopneumoniae to cell monolayers.this work was an attempt to develop an in vitro adherence model for mycoplasma hyopneumoniae, using monolayers of human and porcine lung fibroblasts and porcine kidney cells. mycoplasma hyopneumoniae grown in friis mycoplasma broth was radiolabeled with 35[s]-methionine, washed, concentrated, and inoculated on the monolayers. after 15 minutes of centrifugation to facilitate adherence, monolayers were washed 3 times, dissolved with 0.1n naoh, and suspended in scintillation liquid, and the radioac ...19902316909
human ureaplasmas show diverse genome sizes by pulsed-field electrophoresis.contour clamped homogeneous field (chef) agarose gel electrophoresis (age), ramped to give linear separation of dna molecules of 600-1600 kilobase pairs (kbp), was used to determine mobilities for full-sized genomic dna of the serotype standard strains of the human genital mollicutes, ureaplasma urealyticum relative to yeast chromosomal dna markers. indicated genome sizes (in kbp) were 760 for the four biotype 1 strains and 840-1140 for eleven biotype 2 strains. other estimates were: 720 for myc ...19902326188
humoral and cellular immune responses of pigs inoculated with mycoplasma hyopneumoniae.cellular and humoral immune responses of pigs inoculated with mycoplasma hyopneumoniae were investigated at postinoculation weeks (piw) 2, 4, and 6. the response of blood lymphocytes (bl) and bronchial lymph node lymphocytes (lnl) to stimulation by m hyopneumoniae antigens was evaluated by a lymphocyte-stimulation test. specific antibodies in serum and lung washing samples were assayed by elisa. immunoglobulin-positive cells in lungs and bronchial lymph nodes were identified by indirect fluoresc ...19902405753
identification and mapping of an immunogenic region of mycoplasma hyopneumoniae p65 surface lipoprotein expressed in escherichia coli from a cloned genomic fragment.a previously characterized lipid-modified amphiphilic surface protein of mycoplasma hyopneumoniae, p65, has been defined by its reaction with a surface-binding monoclonal antibody (mab) and by its exclusive partitioning into the detergent phase during triton x-114 phase fractionation (k. s. wise and m. f. kim, j. bacteriol. 169:5546-5555, 1987). in the current study, polyclonal mouse antibody (pab) to gel-purified p65 was used to identify recombinant phage plaques expressing p65-related epitopes ...19901695206
bronchiolar metaplasia and ulex europaeus agglutinin i (uea-i) affinity in mycoplasma hyopneumoniae-infected lungs of six pigs. 19911722926
use of antibodies against the p36 protein of mycoplasma hyopneumoniae for the identification of m. hyopneumoniae strains.mycoplasma hyopneumoniae, the principal aetiological agent of porcine enzootic pneumonia, synthesizes a 36 kda protein (p36) which is an early and strong immunogenic factor in experimentally and naturally infected swine. polyclonal antibodies were made against the recombinant p36 protein in rabbits and used for the identification of m. hyopneumoniae by the immunoblot technique. the proteins from the m. hyopneumoniae reference strains and from 13 m. hyopneumoniae field strains isolated from natur ...19911723490
morphological and ultrastructural studies of mycoplasma flocculare and mycoplasma hyopneumoniae in vitro.cells of mycoplasma flocculare were found to vary in size and shape, especially in the later phases of growth, whereas those of mycoplasma hyopneumoniae were fairly uniform irrespective of growth phases. filamentous cells were present in cultures of m flocculare in the stationary and declining phases, but were never found in cultures of m hyopneumoniae. the filamentous and bizarre forms observed when mycoplasmas were suspended in phosphotungstic acid probably result from the action of the hypoto ...19911724093
serological response to actinobacillus pleuropneumoniae serovar 7 infection in a commercial pig herd.serological responses to actinobacillus pleuropneumoniae serovar 7 infection were monitored by enzyme-linked immunosorbent assay in a cohort of 66 pigs between weaning and market. antibody concentrations were high (63/65 seropositive) at 4 weeks of age but declined to low levels from 8 to 12 weeks. mean antibody concentrations rose significantly (p less than 0.001) between 12 and 23 weeks. between 8 and 23 weeks of age, 33 (51.5%) of 64 surviving pigs seroconverted to a pleuropneumoniae serovar ...19911776931
intraperitoneal vaccination of pigs to control mycoplasma hyopneumoniae.in a field trial at a commercial piggery 22 pigs were vaccinated intraperitoneally, at 30 days and 60 days old, with formalin-killed mycoplasma hyopneumoniae plus adjuvant. two other groups of the same size, one receiving a ration containing antibiotics, were not vaccinated. the mean enzyme-linked immunosorbent assay (elisa) ratio of the vaccinated group increased significantly (p less than 0.001) after 30 days, and continued to rise until day 156 of life. in the other two groups the elisa ratio ...19911780583
epidemiological associations between mycoplasma hyopneumoniae and actinobacillus pleuropneumoniae antibody titers and lung lesions in prince edward island swine herds.a survey of anteroventral (av) lung lesions, pleuritis and serology for mycoplasma hyopneumoniae (mh) and actinobacillus pleuropneumoniae (ap) was conducted on a minimum of 25 slaughter hogs from each of 18 randomly sampled prince edward island farms (producing over 1,000 market hogs per year). the data were analyzed to evaluate the potential role of these two agents as risk factors for the two conditions, using crude and multivariable techniques, as well as individual and herd data. anteroventr ...19911790490
preparation of enteric-coated microspheres of mycoplasma hyopneumoniae vaccine with cellulose acetate phthalate: (ii). effect of temperature and ph on the stability and release behaviour of microspheres.the in vitro stability (temperature and ph) and dissolution study (ph 7.4 phosphate buffer solution and ph changed medium) of the enteric-coated microspheres containing mycoplasma hyopneumoniae vaccine (mhv) were examined. the mhv microspheres were thermally more stable than the unencapsulated mhv. more than 90% of antigenicity was retained in the mhv microspheres for 3 weeks when stored at 4 degrees c. the mhv microspheres in ph 1.2 and ph 3.0 medium were more stable than the unencapsulated mhv ...19911798023
[immunobiological characteristics of mycoplasma hyopneumoniae antigens and the diagnosis of infection caused by this organism].the paper presents the developed variants of enzyme immunoassay (eia) using two m. hyopneumoniae (r-14 strain) antigens obtained by biomass freezing and thawing and two tween-dissolved antigens by gel chromatography. to identify the cultures isolated, an indirect immunofluorescence reaction was proposed by employing agar blocks. the developed methods made it possible to identify 23 bovine-isolated cultures as m. hyopneumoniae antigens. the latter were detected by eia in diagnostically significan ...19911927043
preparation of enteric-coated microspheres of mycoplasma hyopneumoniae vaccine with cellulose acetate phthalate: i. formation condition and micromeritic properties.the solvent evaporation method was employed to encapsulate mycoplasma hyopneumoniae vaccine (mhv) using cellulose acetate phthalate (cap) as an enteric coating material. glucose was used as a diluent. the effect of some factors, such as encapsulating temperature, surfactant concentration, mechanical agitation and cap concentration on the formation condition, particle size distribution, morphology, surface topography and antigen content of mhv microspheres, was investigated. the result indicates ...19911941438
an abattoir survey of pneumonia and pleuritis in slaughter weight swine from 9 selected herds. i. prevalence and morphological description of gross lung lesions.the prevalence and pathomorphology of gross lung lesions were studied in 855 slaughter weight pigs from 9 selected herds in south-eastern norway. pneumonic or pleuritic lesions were found in 84% of the lungs, ranging from 37% in the least affected herd to 97% in the one most affected. bronchopneumonia indicative of a primary mycoplasma hyopneumoniae infection was found in 70% of the lungs, ranging from 9% to 82% in the individual herds. the amount of bronchopneumonic lesions in individual lungs ...19911950852
an abattoir survey of pneumonia and pleuritis in slaughter weight swine from 9 selected herds. ii. enzootic pneumonia of pigs: microbiological findings and their relationship to pathomorphology.lungs from 191 slaughter pigs with gross lesions indicative of enzootic pneumonia of pigs (epp) and 80 grossly normal lungs, all originating from 9 different herds, were subjected to microbiological and pathological examinations. the microbiological studies included both bacterial and mycoplasmal culture and also testing for mycoplasma hyopneumoniae antigen in tissue by indirect immunofluorescent technique. m. hyopneumoniae, pasteurella multocida and mycoplasma hyorhinis were detected in 83%, 43 ...19911950853
an abattoir survey of pneumonia and pleuritis in slaughter weight swine from 9 selected herds. iii. serological findings and their relationship to pathomorphological and microbiological findings.blood samples from 777 pigs, originating from 9 different herds, were collected at slaughter and examined for antibodies to mycoplasma hyopneumoniae and actinobacillus (haemophilus) pleuropneumoniae by the indirect hemagglutination assay (iha) and the complement fixation (cf) test, respectively. results were compared to pathological and microbiological findings. antibodies to m. hyopneumoniae in positive titers of 1/80 or higher were found in 62% of the samples. the relationship between positive ...19911950854
interactions of mycoplasma hyopneumoniae membranes with porcine lymphocytes.nonspecific mitogenicity of mycoplasma hyopneumoniae membranes for blood lymphocytes (bl) and bronchial lymph node lymphocytes (lnl) from swine was investigated. additionally, the influence of respiratory tract exposure to the same membrane preparation on responsiveness of these cells was evaluated. membranes utilized in lymphocyte transformation tests and for inoculation of swine were prepared by osmotic lysis of mycoplasma cells. conventionally reared and cesarean-derived, colostrum-deprived s ...19911952341
cloning and expression of a species-specific early immunogenic 36-kilodalton protein of mycoplasma hyopneumoniae in escherichia coli.mycoplasma hyopneumoniae, the etiologic agent of porcine enzootic pneumonia, synthesizes a 36-kda protein which is an early and strong immunogenic factor in experimentally and naturally infected swine. the gene encoding this protein was cloned by screening a gene library of m. hyopneumoniae dna with rabbit hyperimmune serum made against whole m. hyopneumoniae cells and convalescent-phase swine serum. analysis of the recombinant protein expressed in escherichia coli by immunoblot techniques showe ...19912004806
detection of mycoplasma hyopneumoniae dna by the polymerase chain reaction.dna amplification by the polymerase chain reaction (pcr) was examined to detect dna of mycoplasma hyopneumoniae, an etiological agent of porcine pneumonia. a pair of synthetic primers was selected that specify the amplification of a 520-basepair dna fragment in a reiterative sequence of m. hyopneumoniae genome. the pcr product was detected by direct gel electrophoresis or by blot hybridization to a synthetic oligonucleotide probe. the specificity of pcr for m. hyopneumoniae was confirmed by lack ...19912072931
identification of mycoplasma hyopneumoniae with a dna probe.from a genomic library of mycoplasma hyopneumoniae a 1.3 kb dna fragment was cloned which showed specific southern hybridization and dot hybridization with the type strain of several porcine and bovine mycoplasma species. this probe selectively recognized m. hyopneumoniae sequences in purified dna or in broth-grown organisms. the 35s-labelled probe could detect as little as 100 pg of dna or 10(5) colour changing units. this is a possible alternative diagnostic procedure for enzootic pneumonia of ...19911368700
phylogenetic relationships of three porcine mycoplasmas, mycoplasma hyopneumoniae, mycoplasma flocculare, and mycoplasma hyorhinis, and complete 16s rrna sequence of m. flocculare.the nucleotide sequence of the 16s rrna gene of mycoplasma flocculare was determined and was compared with the sequence of a related porcine mycoplasma, mycoplasma hyopneumoniae. while the overall level of dna-dna homology was approximately 11%, sequence alignment of the two 16s rrna genes yielded a homology value of more than 95%, emphasizing the highly conserved nature of the 16s rrna gene. multiple sequence alignments with other mollicutes indicated that m. flocculare, m. hyopneumoniae, and m ...19921374621
specificity of oligonucleotide probes complementary to evolutionarily variable regions of 16s rrna from mycoplasma hyopneumoniae and mycoplasma hyorhinis.mycoplasma is the common name for the smallest free-living microorganisms, the mollicutes. mycoplasma hyopneumoniae is of great importance in veterinary medicine, causing enzootic pneumonia in pigs. m hyorhinis can cause polyserositis and may cause pneumonia in piglets. oligonucleotides complementary to variable regions of 16s rrna from these mycoplasmas were designed and used as probes for detection and identification of these mycoplasmas. the probe complementary to 16s rrna of m hyorhinis gave ...19921374926
detection of mycoplasma hyopneumoniae by using rrna-oligodeoxynucleotide hybridization.a system that uses rrna-oligodeoxynucleotide hybridization was developed for the detection of mycoplasma hyopneumoniae. synthetic oligonucleotide mhp1 was hybridized specifically with m. hyopneumoniae. furthermore, the detection of m. hyopneumoniae in clinical samples, such as bronchoalveolar lavage fluid and lung lesions from experimentally infected pigs, was evaluated by this assay. the evidence obtained from the assay indicated that the system can be used to efficiently diagnose mycoplasmal p ...19921378059
construction of the physical maps of mycoplasma hyopneumoniae and mycoplasma flocculare and the location of rrna genes on these maps.the genomes of mycoplasma flocculare and mycoplasma hyopneumoniae, two mycoplasmas of the porcine respiratory system, were studied. based upon antigenic cross-reactivity and dna-dna hybridization, these species have given indication of a close genetic relationship. by using field-inversion gel electrophoresis and employing the restriction digest fragments obtained from the gels as the probes, physical maps of the genomes of the two species were constructed. mycoplasma hyopneumoniae is similar to ...19921382823
evaluation of a monoclonal blocking elisa and iha for antibodies to mycoplasma hyopneumoniae in spf-pig herds.a monoclonal blocking enzyme-linked immunosorbent assay (elisa) and an indirect haemagglutination assay (iha) were applied to serum samples from 124 specific pathogen-free (spf) breeding and multiplying herds, which participate in the routine serological surveillance of the danish spf programme. clinical and pathological observations of the herds and microbiological culturing of mycoplasma hyopneumoniae were used to calculate herd sensitivity, herd specificity and herd predictive values for the ...19921386483
detection of mycoplasma hyopneumoniae by using rrna-oligodeoxynucleotide hybridization. 19921401035
protective effects of an oral microencapsulated mycoplasma hyopneumoniae vaccine against experimental infection in pigs.oral microencapsulated mycoplasma hyopneumoniae vaccines were tested for their ability to prevent mycoplasmal pneumonia in pigs. eighteen four-week-old specific pathogen free pigs were divided into six groups of three. each pig of groups 1 to 4 was inoculated intramuscularly with formalin-inactivated m hyopneumoniae in adjuvant and boosted orally 14 days later with four different microencapsulated vaccine microspheres. group 5 was used as a positive control. all 15 pigs of groups 1 to 5 were cha ...19921410817
histochemical and morphologic changes of porcine airway epithelial cells in response to infection with mycoplasma hyopneumoniae.mycoplasma hyopneumoniae causes pneumonia in pigs. the effect of infection by this organism on histochemical characteristics of airway mucin within epithelial cells was studied. seven- to 10-week-old pigs were inoculated intratracheally with m hyopneumoniae or culture broth, and lung tissues were collected from inoculated and control pigs at 2, 4, and 6 weeks after inoculation. tissue sections were stained with periodic acid-schiff/alcian blue, ph 2.5 or high iron diamine/alcian blue. histologic ...19921416380
in vitro colonization of porcine trachea by mycoplasma hyopneumoniae.porcine tracheae maintained in culture were used in order to study the colonization by mycoplasma hyopneumoniae. rings excised from tracheae of newborn piglets were infected with m hyopneumoniae strain bq 14 and, after different incubation times, were examined by light and electron microscopy. non-infected tracheal mucosae maintained a normal appearance for several days. infected tracheal rings showed progressive colonization with concomitant progressive damage to the mucosal surface. early on d ...19921416728
evaluation of an enzyme-linked immunosorbent assay for the detection of mycoplasma hyopneumoniae antibody in porcine serum.an enzyme-linked immunosorbent assay (elisa) for detecting antibody to mycoplasma hyopneumoniae in porcine serum is described. the results are presented as an elisa ratio, calculated by dividing the absorbance of the test sample by the mean absorbance of control negative sera. in known infected pigs, the elisa ratio was highest when the serum concentration applied to the elisa plate was diluted 1 in 20 in pbs - tween. mean elisa ratios ranged from 1.2 +/- 0.3 for pigs without porcine enzootic pn ...19921445072
in vitro stimulation of antibody production to mycoplasma hyopneumoniae by porcine peripheral blood mononuclear cells.a method to stimulate and detect the in vitro production of antibodies to mycoplasma hyopneumoniae by porcine peripheral blood mononuclear cells (pbmc) was established. pbmc were cultured in microtiter plates coated with a sonicated m. hyopneumoniae whole cell antigen and the amount of antibody bound to the coating antigen was determined by an enzyme linked immunosorbent assay (elisa). in addition, the amount of non-bound antibody was determined by testing the culture supernatants in the elisa w ...19921455630
a specific dna probe for detecting mycoplasma hyopneumoniae in experimentally infected piglets.mycoplasma hyopneumoniae is the primary agent of swine enzootic pneumonia. because of fastidious growth requirements and its serological cross-reactions with other porcine mycoplasmas, we developed a specific dna probe for its detection. a partial genomic library of m. hyopneumoniae was constructed in plasmid pbr 322 using hind iii chromosomal fragments. the recombinant plasmids were screened by differential hybridization with m. flocculare and m. hyorhinis genomic dna probes. one non-hybridizin ...19921474981
a monoclonal blocking elisa detecting serum antibodies to mycoplasma hyopneumoniae.a monoclonal blocking enzyme-linked immunosorbent assay (elisa) for detection of antibodies to mycoplasma hyopneumoniae in porcine serum has been developed. the monoclonal antibody (mab) reacts with an m. hyopneumoniae specific epitope on a molecule of approximately 74 kda. only sera from m. hyopneumoniae infected pigs were able to block the binding of the mab although antibodies from m. flocculare infected pigs also recognized a 74 kda molecule. sera from experimentally infected pigs as well as ...19921531562
electron microscopic observation of the respiratory tract of spf piglets inoculated with mycoplasma hyopneumoniae.seven hysterectomy derived piglets were repeatedly challenged with mycoplasma hyopneumoniae during the first week of life. samples of trachea, bronchi and lung tissue collected 2-11 weeks post-inoculation (p.i.) were examined using light and electron microscopy. autoradiography was used to study in more detail the site of m. hyopneumoniae multiplication. gross lesions were observed in lung tissue and were characterized by hyperplasia of the epithelium and an increased mononuclear cell accumulati ...19921533978
immunological and pathological reactions in piglets experimentally infected with mycoplasma hyopneumoniae and/or mycoplasma flocculare.the aim of this work was to examine in vivo whether infection with mycoplasma hyopneumoniae (m. hyop) and/or mycoplasma flocculare (m. floc) would interact and influence the severity of enzootic pneumonia in piglets. specific pathogen-free, hysterectomy-derived piglets were allocated to six groups and experimentally inoculated with m. hyop. and/or m. floc at the age of 2 or 8 weeks. clinical symptoms, frequency of coughing and temperature measurement were noted daily. lung lesions were recorded ...19921570675
chromosomal heterogeneity of various mycoplasma hyopneumoniae field strains.restriction enzyme digestion and field inversion gel electrophoresis were used to analyze the chromosomes of strains of mycoplasma hyopneumoniae and the related organism mycoplasma flocculare. the chromosome size for the m. hyopneumoniae type strain was calculated from individual fragments to be 1,011.3 +/- 32.9 kbp. the chromosomes of m. hyopneumoniae field strains were approximately the same size. the restriction patterns obtained for the chromosomes of phenotypically similar m. hyopneumoniae ...19921316139
morphologic features and hydrophobicity of the cell surface of mycoplasma hyopneumoniae.cell surface hydrophobicity of mycoplasma hyopneumoniae was evaluated by phase partitioning in a hydrocarbon-aqueous mixture, by hydrophobic interaction chromatography, and by salting out with ammonium sulfate. results obtained by use of these techniques gave evidence that the cell surface of m hyopneumoniae is weakly hydrophobic, compared with strongly hydrophobic staphylococcus aureus cowan i and hydrophilic klebsiella pneumoniae. after treatment of the organisms with trypsin, m hyopneumoniae ...19921323225
antigenic characteristics and stability of microencapsulated mycoplasma hyopneumoniae vaccine.the in vitro stability (temperature, ph, and trypsin) of mycoplasma hyopneumoniae antigen (mha) with and without enteric-coated microencapsulation were examined. microencapsulation of mha with cellulose acetate phthalate (cap) is an effective route to produce enteric-coated vaccine microspheres for oral administration. the effect of temperature on the rate of inactivation of mha was studied by exposing mha to various temperatures, such as 25, 37, 50 and 60 degrees c. the mha microspheres were th ...199218601105
dna sequence determination and biochemical analysis of the immunogenic protein p36, the lactate dehydrogenase (ldh) of mycoplasma hyopneumoniae.the dna sequence of the gene encoding the early and specific immunogenic protein p36 of mycoplasma hyopneumoniae has been determined. comparison of the dna sequence and the deduced amino acid sequence of p36 with known genes and proteins in data banks indicated that p36 is a l-lactate dehydrogenase (ldh) (ec 1.1.1.27). biochemical analysis of protein p36 expressed from the cloned gene in escherichia coli confirmed that p36 has l-lactate dehydrogenase activity. protein p36 of m. hyopneumoniae the ...19937679720
adherence of mycoplasma hyopneumoniae to porcine ciliated respiratory tract cells.adherence of mycoplasma hyopneumoniae to the mucosa of the distal portion of the respiratory tract of swine is an important initial event in development of mycoplasmal pneumonia. a suitable in vitro model of adherence would be useful for investigation of mycoplasmal and host cell factors involved in this process. we have developed an adherence assay, using suspensions of porcine respiratory tract ciliated epithelial cells and m hyopneumoniae. tracheal epithelial cells, collected by use of cytolo ...19938214893
development of polymerase chain reaction primers to detect mycoplasma hyopneumoniae.mycoplasma hyopneumoniae (mhp) is the etiologic agent of mycoplasma pneumonia in swine. the purpose of this study was to develop a species-specific polymerase chain reaction (pcr)-based diagnostic reagent for the identification of mhp. based upon dna sequence analysis of a cloned fragment of mhp dna, pcr primers were constructed and tested against different strains of mhp, mycoplasma flocculare, other mycoplasma species, and non-mollicute micro-organisms which commonly inhabit the respiratory tr ...19938264672
adaptation of the sensititre broth microdilution technique to antimicrobial susceptibility testing of mycoplasma hyopneumoniae.a broth microdilution technique is described for determining the antimicrobial susceptibility of mycoplasma hyopneumoniae, using commercially prepared sensititre plates. twenty-five field isolates and two reference strains (j & 232), were tested against seven antimicrobials. field isolates were tested in duplicate and reference strains, four times to estimate reproducibility. ninety-seven percent of the duplicate mic results for the field isolates were in agreement, or within one log2 dilution. ...19938273275
serum and mucosal antibody responses against mycoplasma hyopneumoniae following intraperitoneal vaccination and challenge of pigs with m hyopneumoniae.pigs were immunised intraperitoneally when six weeks old and again at about 10 weeks old with killed mycoplasma hyopneumoniae antigen prepared in an oil adjuvant. the pigs were challenged with live m hyopneumoniae (beaufort strain) at between 11 and 15 weeks old. antigen specific antibody levels for both igg and iga classes in serum and respiratory tract secretion were monitored over time. in serum anti-m hyopneumoniae antibody was detected shortly after the second intraperitoneal vaccination an ...19938284503
increased levels of tumor necrosis factor and interleukin 1 in bronchoalveolar lavage fluids from pigs infected with mycoplasma hyopneumoniae.we examined the levels of tumor necrosis factor (tnf)-alpha and interleukin-1 (il-1) in bronchoalveolar lavage fluids (balf) from pigs experimentally infected with mycoplasma hyopneumoniae using biological assays with wehi-164 cells and d10.g4.1 cells, respectively. increased tnf-alpha and il-1 in balf were found in infected pigs with gross and/or microscopic lesions. a time-course study suggested tnf-alpha and il-1 to be persistently elevated in infected pigs. their presence in balf would thus ...19938291203
aerosol vaccination of pigs against mycoplasma hyopneumoniae infection.aerosol vaccination is used effectively to immunize poultry against newcastle disease, but to the authors' knowledge, this vaccination procedure is not well studied in other species. the efficacy of im and aerosol vaccination of pigs against mycoplasma hyopneumoniae infection was evaluated. twenty-one pigs from a mycoplasma-free herd were randomly allotted by litter and body weight into 3 groups. one group was given aerosolized phosphate-buffered saline solution (pbss) by inhalation. the second ...19938291766
mycoplasma hyopneumoniae infection in pigs: duration of the disease and resistance to reinfection.forty-eight hysterectomy produced piglets reared in a pathogen-free environment were housed in 4 separate units. three groups were intratracheally challenged with m hyopneumoniae at 2 wk, or at 16 wk, or at 2 and 16 wk of age. the fourth group was uninfected and received broth medium. coughing started 2 weeks after the first infection but the booster infection did not induce any coughing. macroscopic lesions, typical of mycoplasmal pneumonia, were noted 1 wk post-infection. after 7-9 wk, piglets ...19938319010
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