TitleAbstractYear(sorted ascending)
in vitro susceptibility of avian mycoplasmas to enrofloxacin, sarafloxacin, tylosin, and vitro susceptibility of avian mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) to enrofloxacin, sarafloxacin, tylosin, and oxytetracycline was determined by a serial broth dilution method. the minimum inhibitory concentration (mic) was recognized by a conversion of the ph indicator phenol red in culture media to a yellow color. each isolate or type strain of mycoplasma was tested in two replicates. the mics of tylosin, enrofloxacin, sarafloxacin, and oxytetracycline against five iso ...200111417828
monitoring mycoplasma gallisepticum and mycoplasma synoviae infection in breeder chickens after treatment with enrofloxacin.three experimental strains of breeder chickens were accidentally exposed to mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms), presumably from a newly introduced group of leghorn-type pullets. the experimental strains subsequently became infected and were diagnosed positive for mg and ms by the serum plate agglutination (spa) test and confirmed by the hemagglutination inhibition (hi) test and the polymerase chain reaction (pcr) of tracheal swabs. treatment with 10 mg/kg enrofloxacin via ...200111417841
mycoplasmosis in evening and pine grosbeaks with conjunctivitis in outbreak of conjunctivitis affected evening grosbeaks (coccothraustes vespertinus) and pine grosbeaks (pinicola enucleator) in quebec (canada) during the winter 1998-99. one to 30% of the individuals from these two species were sick at 13 feeding stations. sick birds were thin and had unilateral or bilateral catarrhal and lymphoplasmacytic conjunctivitis and rhinitis, and mucopurulent infra-orbital sinusitis. mycoplasmal organisms were isolated in cultures in an affected evening grosbeak and ...200111763749
mycoplasmas and respiratory disease in pheasants and partridges.pheasants and partridges with signs of upper respiratory disease were cultured for mycoplasmas and were also examined for mycoplasma gallisepticum and mycoplasma synoviae using commercial polymerase chain reaction (pcr) kits. sixty-two incidents of disease were investigated in pheasants and 12 in partridges. m. gallisepticum was detected by culture in only four and three incidents in pheasants and partridges, respectively, but with pcr a further 15 m. gallisepticum-positive incidents were detect ...200119184924
trinucleotide gaa repeats dictate pmga gene expression in mycoplasma gallisepticum by affecting spacing between flanking regions.the pmga genes of the avian respiratory pathogen mycoplasma gallisepticum encode a family of hemagglutinins that are subject to phase variation. a trinucleotide gaa repeat region is located upstream of the pmga transcription start site. the length of the repeat region varies at a high frequency due to changes in the number of repeat units. previous studies have shown that pmga genes are transcribed when 12 gaa repeats are present but are not transcribed when the number of repeats is not 12. to f ...200211844762
infectious agents associated with respiratory disease in a case-control study of the infectious agents associated with natural outbreaks of respiratory disease in pheasants, 28 batches of birds from sites affected by disease and eight batches of birds from unaffected sites were examined by six veterinary laboratories in england, wales and scotland, and tested for mycoplasmas, other bacteria and viruses. sinusitis was the commonest sign of disease and was associated with mycoplasma gallisepticum as detected by pcr in the trachea (p < 0.05) and conju ...200212054135
domain-level differences in microsatellite distribution and content result from different relative rates of insertion and deletion mutations.microsatellites (short tandem polynucleotide repeats) are found throughout eukaryotic genomes at frequencies many orders of magnitude higher than the frequencies predicted to occur by chance. most of these microsatellites appear to have evolved in a generally neutral manner. in contrast, microsatellites are generally absent from bacterial genomes except in locations where they provide adaptive functional variability, and these appear to have evolved under selection. we demonstrate a mutational b ...200211875028
construction of mini-tn4001tet and its use in mycoplasma gallisepticum.the mollicutes are a group of cell-wall-less bacteria and are important plant and animal pathogens. progress toward analyzing their pathogenic mechanisms has been hampered by the few available genetic tools. of the two transposons shown to function in mycoplasmas, only tn4001 is readily amenable to modification and development. one disadvantage of using tn4001 in mycoplasmas has been independent insertion of the insertion sequence, is256, probably as a result of inadequate control of the transpo ...200211982334
characterization of mutations in dna gyrase and topoisomerase iv involved in quinolone resistance of mycoplasma gallisepticum mutants obtained in vitro.mycoplasma gallisepticum enrofloxacin-resistant mutants were generated by stepwise selection in increasing concentrations of enrofloxacin. alterations were found in the quinolone resistance-determining regions of the four target genes encoding dna gyrase and topoisomerase iv from these mutants. this is the first description of such mutations in an animal mycoplasma species.200211796386
the macrophage inflammatory protein-1beta in the supernatants of mycoplasma gallisepticum-infected chicken leukocytes attracts the migration of chicken heterophils and lymphocytes.chicken monocytes, macrophages, heterophils and thrombocytes were infected with mycoplasma gallisepticum, and their supernatants were collected and tested for the presence of chemotactic activities. the supernatants from mg-infected monocytes and macrophages were able to attract the migration of both heterophils and lymphocytes. the chemotactic activity in these supernatants could be abolished by antibodies prepared against the 10 amino acid peptides of the macrophage inflammatory protein (mip)- ...200211687266
effects of an s6 strain of mycoplasma gallisepticum challenge before beginning of lay on various egg characteristics in commercial layers.mycoplasma gallisepticum (mg) is a reproductive/respiratory disease in poultry implicated in suboptimum egg production and decreased hatchability. commercial layer hens raised in a controlled environment were inoculated with the s6 strain of mg at 10 wk of age. egg production and selected egg and egg quality parameters were quantitated over the entire lay cycle for inoculated and control birds. the s6 inoculation had no effect on bird weight, egg production, associated egg quality parameters, or ...200212243522
poor systemic antibody response after vaccination of commercial broiler breeders with mycoplasma gallisepticum vaccine ts-11 not associated with susceptibility to challenge.a live attenuated mycoplasma gallisepticum vaccine, ts-11, has been used for control of m gallisepticum in several countries. the rapid serum agglutination test is usually used as an indicator of flock response to vaccination; however, in some flocks, the detected response may be weak or absent. we investigated whether the low level, or lack, of systemic antibodies in ts-11-vaccinated flocks is correlated with susceptibility to infection after challenge with a virulent m. gallisepticum strain. b ...200212243526
a modified live mycoplasma gallisepticum vaccine to protect chickens from respiratory disease.the aim of this study was to assess the efficacy of a modified live mycoplasma gallisepticum vaccine (gt5) for the protection of chickens against infection and respiratory disease. gt5 was constructed by the reconstitution of the avirulent high passage r (r(high)) strain with the gene encoding the major cytadhesin gapa. gt5 expressed gapa on its surface yet retained the phenotypic characteristics of the parental r(high) strain. birds vaccinated with gt5 were protected upon challenge with the vir ...200212399199
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on performance and egg characteristics of commercial egg-laying hens.the effects of f-strain mycoplasma gallisepticum (fmg) inoculation during the pullet period on the subsequent performance and egg characteristics of commercial single combed white leghorn hens were evaluated. in two trials, bw, feed consumption, egg production (ep), egg weight, egg size class, relative eggshell water vapor conductance, and relative percentages of eggshell, yolk and albumen weights were determined through approximately 60 wk of age. in each trial, pullets at 12 wk of age were ran ...200212412912
mycoplasma gallisepticum rpoa gene cluster.two conservative gene clusters, the s10 ribosomal protein region and one (of the two) set of rrna genes, were split in a genome crossover rearrangement event in mycoplasma gallisepticum. as a result of the rearrangement the major part of the s10 ribosomal protein cluster is located upstream of genes for 23s-5s rrna (rrn23-5), but the genes infa-rpl36-rps13-rpoa-rpl17 are located immediately downstream of the isolated gene for 16s rrna (rrn16). a new ribosomal protein cluster infa-rpl36-rps13-rpo ...200211959450
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on digestive and reproductive organ characteristics of commercial egg laying hens.experimental inoculation with the f-strain of mycoplasma gallisepticum (fmg) between 8 and 18 wk of age is known to affect reproductive performance in commercial layers. therefore, two trials were conducted to determine if changes in digestive and reproductive organ characteristics also occur in commercial laying hens infected with fmg at 12 wk of age. in trial 1, liver weight, liver lipid and moisture contents, ovary weight, ovarian follicular hierarchy, and the weights, lengths, and histologie ...200212512582
the effects of 6/85 live mycoplasma gallisepticum vaccine in commercial layer hens over a 43-week laying cycle on egg production, selected egg quality parameters, and egg size distribution when challenged before beginning of each of two trials, 80 commercial leghorn-type pullets were separated into two treatments with four replicates of 10 chickens in each treatment. forty pullets were designated as controls and received no inoculation, whereas the remaining 40 pullets received the 6/85 vaccine strain of mycoplasma gallisepticum (mg) at 10 wk of age. hen-day egg production, egg weight, eggshell strength, haugh unit score, pimpling incidence, and blood/meat spot incidence were monitored and recorded weekly in each ...200212061653
haemagglutinins of pathogenic avian mycoplasmas.the pathogenic avian mycoplasmas, mycoplasma gallisepticum, mycoplasma synoviae, mycoplasma meleagridis, mycoplasma iowae and mycoplasma imitans, synthesize haemagglutinins that are immunogenic, variably expressed, surface proteins. the haemagglutinins of m. gallisepticum (pmga), m. synoviae (vlha) and m. imitans are lipoproteins, encoded by related multigene families that appear to have arisen by horizontal gene transfer. m. gallisepticum also has genes encoding cytadhesins in its genome but th ...200212593736
detection of antibodies to mycoplasma gallisepticum vaccine ts-11 by an autologous pmga enzyme-linked immunosorbent assay.mycoplasma gallisepticum is a poultry pathogen that causes respiratory disease and loss of egg production worldwide. a live attenuated vaccine, ts-11, has been used for control of m. gallisepticum in several countries. the rapid serum agglutination test is usually used as an indicator of flock response to vaccination; however, in some flocks, the detected response may be weak or absent. with the use of specific monoclonal antibodies against m. gallisepticum strain s6 pmga in immunoaffinity purif ...200212061651
[in vitro resistance acquisition in mycoplasma gallisepticum against ofloxacin, tylosin and spectinomycin].to clarify a mechanism of acquired resistance of two mycoplasma gallisepticum (mg) strains against ofloxacin (oflx) along with tylosin (ts) and spectinomycin (spcm) as the controls, in vitro resistance acquisition test was carried out for 10 subcultures of each strain with increasing the amount of antimicrobials, and maximum growth allowance concentrations (mac) in 10th and primary subcultures were compared. acquisition of resistance in the strains against oflx was moderate and mac of the 10th s ...200212199113
mycoplasma gallisepticum: influence of cell invasiveness on the outcome of experimental infection in chickens.recently we have shown that a low (r(low)) and a high laboratory passage (r(high)) of the poultry pathogen mycoplasma gallisepticum prototype strain r differ markedly in their capability to invade non-phagocytic eukaryotic cells. in the present study the infection traits of these two mycoplasma passages were compared in an in vivo setting. after aerosol inoculation of chickens, m. gallisepticum was re-isolated from the inner organs of birds infected with r(low), whereas no mycoplasma was recover ...200212423769
pathogenesis of avian pneumovirus infection in turkeys.avian pneumovirus (apv) is the cause of a respiratory disease of turkeys characterized by coughing, ocular and nasal discharge, and swelling of the infraorbital sinuses. sixty turkey poults were reared in isolation conditions. at 3 weeks of age, serum samples were collected and determined to be free of antibodies against apv, avian influenza, hemorrhagic enteritis, newcastle disease, mycoplasma gallisepticum, mycoplasma synoviae, mycoplasma meleagridis, ornithobacterium rhinotracheale, and borde ...200212014494
susceptibility of a naïve population of house finches to mycoplasma gallisepticum.since 1994 an epidemic of mycoplasmal conjunctivitis has spread throughout the eastern house finch (carpodacus mexicanus) population leading to a significant decline in this population. the infection has not yet been reported from house finch populations west of the great plains. we hypothesized that the western population, like the eastern population, is susceptible to infection, and we tested this hypothesis by experimentally infecting house finches from missoula, montana (usa) with the house ...200212038126
field evaluation of tylosin premix in layers previously vaccinated with a live mycoplasma gallisepticum vaccine.mycoplasma gallisepticum infection results in numerous clinical signs including a reduction in egg production in laying chickens. attempts to prevent mycoplasmosis have included vaccination with both killed and attenuated live m. gallisepticum strains. live vaccines provide reduction in clinical signs and have been shown to replace indigenous strains when used in a consistent program for several placements. antibiotic therapy is another option for controlling losses associated with mycoplasmosis ...200211922337
fluoroquinolone resistance in mycoplasma gallisepticum: dna gyrase as primary target of enrofloxacin and impact of mutations in topoisomerases on resistance level.resistant mutants of mycoplasma gallisepticum were selected in vitro by passaging strains 10 times in increasing concentrations of enrofloxacin. the regions of gyra/gyrb and parc/pare, encoding the quinolone resistance-determining regions (qrdrs) of dna gyrase and dna topoisomerase iv, respectively, of the mutants obtained during different passages were sequenced. several mutations were found in the four fluoroquinolone targets. substitution of ser-83-->arg in gyra and ser-80-->leu or trp in par ...200212356806
in vitro development of resistance to enrofloxacin, erythromycin, tylosin, tiamulin and oxytetracycline in mycoplasma gallisepticum, mycoplasma iowae and mycoplasma synoviae.the in vitro emergence of resistance to enrofloxacin, erythromycin, tylosin, tiamulin, and oxytetracycline in three avian mycoplasma species, mycoplasma gallisepticum, mycoplasma synoviae and mycoplasma iowae was studied. mutants were selected stepwise and their mics were determined after 10 passages in subinhibitory concentrations of antibiotic. high-level resistance to erythromycin and tylosin developed within 2-6 passages in the three mycoplasma species. resistance to enrofloxacin developed m ...200212119137
the necessity of combining genomic and enzymatic data to infer metabolic function and pathways in the smallest bacteria: amino acid, purine and pyrimidine metabolism in mollicutes.bacteria of the class mollicutes have no cell wall. one species, mycoplasma genitalium is the personification of the simplest form of independent cell-free life. its small genome (580 kbp) is the smallest of any cell. mollicutes have unique metabolic properties, perhaps because of their limited coding space and high mutability. based on 16s rrna analyses the mollicutes mycoplasma gallisepticum is thought to be the most mutable bacteria. enzyme activities found in most bacteria are absent from mo ...200212133816
development and application of a multiplex polymerase chain reaction for avian respiratory agents.a multiplex polymerase chain reaction (pcr) was developed and optimized to simultaneously detect 6 avian respiratory pathogens. six sets of specific oligonucleotide primers for infectious bronchitis virus (ibv), avian influenza virus (aiv), infectious laryngotracheitis virus (iltv), newcastle disease virus (ndv), mycoplasma gallisepticum (mg), and mycoplasma synoviae (ms) were used respectively in the test. with the use of agarose gel electrophoresis for detection of the pcr-amplified dna produc ...200212243534
prevalence of mycoplasma antibodies in lesser prairie-chicken sera.serologic testing by the serum plate agglutination (spa) procedure was performed to detect the presence of cross-reacting antibodies to mycoplasma meleagridis, mycoplasma synoviae, and mycoplasma gallisepticum in lesser prairie-chickens (tympanuchus pallidicinctus) trapped over a 2-yr period in finney and kearny counties of southwestern kansas. sera examined from birds (n = 50) obtained in march-april 2000 tested positive for m meleagridis, m. synoviae, and m. gallisepticum at levels of 6%, 10%, ...200212243537
serological monitoring of 40 swiss fancy breed poultry flocks.rapid serum agglutination, haemagglutination inhibition and enzyme-linked immunosorbent assays were used to screen swiss fancy breed chicken flocks for antibodies against 12 avian infectious agents. for this purpose, 1,002 blood samples from 40 flocks were collected and tested. ten percent of the samples were positive for salmonella gallinarum-pullorum and 62.5% of the flocks were affected. more than 75% of the flocks had antibodies against mycoplasma gallisepticum/mycoplasma synoviae, infectiou ...200212396360
polymerase chain reaction for detection of mycoplasma gallisepticum in environmental samples.the polymerase chain reaction (pcr) was used to detect mycoplasma gallisepticum in samples collected from the environment of experimentally or naturally infected poultry. culture was also used in the experimental infections. of 160 samples of food, drinking water, feathers, droppings or dust collected during experimental infection, 103 were positive using a m. gallisepticum-specific pcr (mg-pcr) and 68 were positive using a pcr (mycoplasma-pcr) that detects all species of the genera mycoplasma, ...200212396361
occurrence of conjunctivitis, sinusitis and upper region tracheitis in japanese quail (coturnix coturnix japonica), possibly caused by mycoplasma gallisepticum accompanied by cryptosporidium sp. infection.on a farm raising approximately 75,000 japanese quail (coturnix coturnix japonica) for egg production, the diseased quail showed clinical signs of swelling of the head, nasal discharge, increased lacrimation, and decreased egg production. the flock experienced a mortality rate of 5.7% per day. macroscopic observation revealed large, gelatinous masses of caseous exudate in the sinuses, egg peritonitis, and airsacculitis. microscopically, non-purulent or purulent inflammation accompanied by lympho ...200212396337
natural cases and an experimental study of h9n2 avian influenza in commercial broiler chickens of iran.since 1998, an epidemic of avian influenza has occurred in the iranian poultry industry. the agent was pathotyped as non-highly pathogenic and subtyped as an h9n2 avian influenza virus. therefore it did not require eradication. however, frequent incidences of high mortality were observed commonly on broiler farms. no other species of bird were affected. the circulation of the virus and mixed infection with other respiratory pathogens, particularly infectious bronchitis virus and mycoplasma galli ...200212396348
gapa and crma coexpression is essential for mycoplasma gallisepticum cytadherence and was previously demonstrated that avirulent mycoplasma gallisepticum strain r(high) (passage 164) is lacking three proteins that are expressed in its virulent progenitor, strain r(low) (passage 15). these proteins were identified as the cytadhesin molecule gapa, the putative cytadhesin-related molecule crma, and a component of a high-affinity transporter system, hata. complementation of r(high) with wild-type gapa restored expression in the transformant (gt5) but did not restore the cytadheren ...200212438360
emerging infectious diseases in wildlife.the processes which give rise to emerging infectious diseases of wildlife can be categorised as follows: ecosystem alterations of anthropogenic or natural origin; movement of pathogens or vectors, via human or natural agency; and changes in microbes or in the recognition of emerging pathogens due to advances in the techniques of epidemiology. these are simplistic divisions because factors influencing the emergence of diseases of wild animals generally fall into more than one category. mycoplasmo ...200211974625
cloning and analysis of the gene for a major surface antigen of mycoplasma gallisepticum.myplasma gallisepticum infects a wide variety of gallineaceous birds including chickens, turkeys, and pheasants. infection occurs both horizontally and vertically. thus, control of the spread of m. gallisepticum to noninfected flocks is difficult. continual monitoring is necessary to identify infected flocks even under the most stringent infectious control practices. monitoring, however, is usually performed by measuring hemagglutination activity (ha) in serum, an insensitive and variable test. ...200212495041
effects of genetic selection for high or low antibody response on resistance to a variety of disease challenges and the relationship of resource allocation.lines of white leghorn chickens were selectively bred for either a high (h) or low (l) antibody response to sheep erythrocytes. the parental lines, hh and ll, and reciprocal crosses, hl (sire line cited first and dam line second) and lh, were compared for their responses to various diseases. high antibody titers were associated with reduced body weight. lines and their crosses were challenged with infectious diseases. the ll line was most resistant to mycobacterium avium, whereas the hh line was ...200212495065
infectious disease survey of rio grande wild turkeys in the edwards plateau of texas.state wildlife agencies have translocated thousands of wild turkeys (meleagris gallopavo) since the 1930s to reestablish this species. because of threats to the domestic poultry industry and wild birds, screening for selected infectious agents has become routine since the early 1980s. one of the principal sources for rio grande wild turkeys (m. gallopavo intermedia) for translocation purposes was the edwards plateau of texas (usa). unfortunately, turkey abundance has declined in the southern edw ...200212528453
infectious disease survey of lesser prairie chickens in north texas.lesser prairie chicken (tympanuchus pallidicinctus) abundance, like that of most grassland birds, has declined rangewide for decades. although habitat loss and degradation are likely ultimate causes for this decline, infectious agents, particularly microparasites, could be proximate contributors. no surveys of pathogenic bacteria or viruses have been published for this species. we surveyed 24 free-living lesser prairie chickens from hemphill county, texas (usa), for evidence of exposure to salmo ...200212528454
chemotactic response of lymphocytes in chicken embryos infected with mycoplasma gallisepticum.a prominent feature of mycoplasma gallisepticum (mg) infection is a lymphoproliferative response at the site of infection. in this study, artificial air cells (aacs) were made in eggs containing 16-day old chicken embryos. an mg culture and supernates from mg-infected rp-9 cells, hd-11 cells and monocytes were separately deposited on the membranes of the aac. after incubation for 5 days, the eggs were opened and the aac membranes were collected for histopathological examinations. immunolabelling ...200312531685
phenotypic switching in mycoplasma gallisepticum hemadsorption is governed by a high-frequency, reversible point mutation.mycoplasma gallisepticum is a flask-shaped organism that commonly induces chronic respiratory disease in chickens and infectious sinusitis in turkeys. phenotypic switching in m. gallisepticum hemadsorption (ha) was found to correlate with phase variation of the gapa cytadhesin concurrently with that of the crma protein, which exhibits cytadhesin-related features and is encoded by a gene located downstream of the gapa gene as part of the same transcription unit. in clones derived from strain r(lo ...200312595441
isolation and characterization of a 6/85-like mycoplasma gallisepticum from commercial laying hens.eighty-three-week-old table egg layers with swollen sinuses were presented with a history of increased mortality. serology revealed positive titers to mycoplasma gallisepticum (mg). the birds were part of a flock in which some birds had been vaccinated with 6/85 live mg vaccine at 18 wk of age. tracheal cultures were obtained from both vaccinated and unvaccinated birds within the flock. the cultures were indistinguishable from 6/85 vaccine by both random amplified polymorphic dna analysis and dn ...200312887214
scanning electron microscopic studies of mycoplasma gallisepticum infection in embryonic tracheae.mycoplasma gallisepticum (mg) was used to infect chicken embryos, and scanning electron microscopy was used to examine the morphologic changes in the tracheae. tracheae harvested from embryos infected with mg for 5 days showed extensive deciliation, surface erosion, and inflammatory cell infiltration. embryonic tracheal explants infected with mg for 6 hr showed the same deciliation and surface erosion. the damage to the tracheal surface caused by mg at the embryonic stage might play a role in th ...200312713177
cytadherence-deficient mutants of mycoplasma gallisepticum generated by transposon mutagenesis.cytadherence-related molecules of mycoplasma gallisepticum strain r-low were identified by tn4001 transposon mutagenesis with the hemadsorption (ha) assay as an indicator for cytadherence. three gm(r) ha-negative (ha(-)) colonies displaying a stable ha(-) phenotype through several successive generations in which gentamicin selection was maintained were isolated from four independent transformation experiments and characterized. southern blot analysis showed that the transposon was inserted as a ...200312819064
diseases of free-ranging chickens in the qwa-qwa district of the northeastern free state province of south africa.a total of 177 free-ranging chickens from 19 qwa-qwa villages were bled from wing veins over a period of 6 months (june-november 2000). serological tests indicated that 5% of chickens tested had been exposed to newcastle disease, 43% to infectious bronchitis and 63% to mycoplasma gallisepticum infection. mcmaster and visser sieve techniques were used to determine helminth and coccidia from pooled fresh faecal samples. helminths isolated in 37% of the villages investigated were heterakis, ascarid ...200312836740
effects of f-strain mycoplasma gallisepticum inoculation on serum very low density lipoprotein diameter and fractionation of cholesterol among lipoproteins in commercial egg-laying hens.experimental inoculation with the f-strain of mycoplasma gallisepticum (fmg) at 12 wk of age has been shown to affect the performance, liver, reproductive organs, and yolk lipid characteristics of commercial layers. therefore, this study was conducted to determine the serum lipoprotein characteristics of commercial egg-laying hens at 16 wk of age and throughout lay after inoculation with fmg at 12 wk of age. mean diameters of very low density lipoproteins (vldl) were determined for the 10th, 50t ...200314601743
effects of an s6 strain of mycoplasma gallisepticum challenge at onset of lay on digestive and reproductive tract characteristics in commercial layers.mycoplasma gallisepticum (mg), a reproductive/respiratory pathogen in poultry, has been implicated in suboptimum egg production and decreased hatchability. commercial layer hens raised in a controlled environment were inoculated with the s6 strain of mg at 20 wk of age. the s6 inoculation had no effect on bird weight, egg production, digestive tract weight and length, or histopathologic lesion scores, although significant differences were noted in the lengths and weights of various portions of t ...200312713163
homologue of macrophage-activating lipoprotein in mycoplasma gallisepticum is not essential for growth and pathogenicity in tracheal organ cultures.while the genomes of a number of mycoplasma species have been fully determined, there has been limited characterization of which genes are essential. the surface protein (p47) identified by monoclonal antibody b3 is the basis for an enzyme-linked immunosorbent assay for serological detection of mycoplasma gallisepticum infection and appears to be constitutively expressed. its gene was cloned, and the dna sequence was determined. subsequent analysis of the p47 amino acid sequence and searches of ...200312670978
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on egg yolk composition in commercial egg laying two trials, the effects of f-strain mycoplasma gallisepticum (fmg) on the contents of egg yolks from commercial single comb white leghorn laying hens were investigated over a production cycle. ten hens were assigned to each of 8 (trial 1) or 16 (trial 2) negative pressure fiberglass biological isolation units. birds in half of the total units served as sham-inoculated controls, and those in the other half were inoculated with fmg at 12 wk of age. eggs were collected and yolks were harvested a ...200312710476
characterisation of mycoplasma gallisepticum strains involved in respiratory disease in pheasants and peafowl.two cases of mycoplasma gallisepticum infection in different avian species in backyard gamebird operations in slovenia were investigated. in the first case, m gallisepticum was associated with severe respiratory disease with almost 20 per cent mortality in pheasants, whereas the infection was less pathogenic for chickens and turkeys reared at the same site. the m gallisepticum isolates from pheasants had a unique pmga gene sequence containing a repeat of 12 nucleotides, and they contained only s ...200312625537
sensory properties of articular afferents following mycoplasma arthritis in the chicken.the physiological properties of joint capsule mechanical nociceptors of monoarthritic chickens (gallus domesticus) were studied by recording the electrical activity from single c (group iv) and a-delta (group iii) fibres dissected from the parafibular nerve. by injecting live mycoplasma gallisepticum cultures into the ankle joint a typical mycoplasma arthritis was induced which was restricted to a single joint. during the early stage of the disease (7-21 days after infection) there was histopath ...200312644261
mycoplasma gallisepticum-induced alterations in chicken red blood cells.incubation of mycoplasma gallisepticum with washed chicken red blood cells for 1 hr or 5 hr resulted in altered red blood cell surface morphology and perforations of the cells.200312887211
influences of supplemental dietary poultry fat and f-strain mycoplasma gallisepticum infection on the early performance of commercial egg laying hens.f-strain mycoplasma gallisepticum (fmg) may alter reproductive performance in layers through its effects on lipid metabolism. therefore, the influences of 1.5% supplemental dietary poultry fat (pf) and fmg infection on the early performance of commercial egg-laying hens were determined. birds were either sham- or fmg-inoculated at 12 wk, and experimental diets were initiated at 20 wk of age. body weight at 12, 20, and 24 wk, total daily egg mass, feed consumption and feed conversion at 20 and 24 ...200312710479
transposon mutagenesis of mycoplasma gallisepticum.there are few systems available for studying the genetics of the important avian respiratory pathogen, mycoplasma gallisepticum. these techniques are needed to develop a mechanism to study the molecular pathogenesis of m. gallisepticum. tn916 has the ability to transpose into the m. gallisepticum genome by both transformation and conjugation. in this study, peg-mediated transformation was employed for the transfer of tn916 into m. gallisepticum and create a transposon mutant library. transforman ...200312583999
survey of peafowl (pavo cristatus) for potential pathogens at three michigan zoos.blood samples collected from 31 free-roaming peafowl from three zoos in michigan were tested serologically. antibody titers were present against avian adenovirus and bordetella avium in 19.3% and 61.3% of the samples, respectively. serum plate agglutination tests were positive for mycoplasma meleagridis and mycoplasma synoviae in 3.2% and 38.7% of the samples, respectively. all birds were seronegative for avian influenza, newcastle disease virus, west nile virus, mycoplasma gallisepticum, salmon ...200315077714
the complete genome sequence of the avian pathogen mycoplasma gallisepticum strain r(low).the complete genome of mycoplasma gallisepticum strain r(low) has been sequenced. the genome is composed of 996,422 bp with an overall g+c content of 31 mol%. it contains 742 putative coding dna sequences (cdss), representing a 91 % coding density. function has been assigned to 469 of the cdss, while 150 encode conserved hypothetical proteins and 123 remain as unique hypothetical proteins. the genome contains two copies of the rrna genes and 33 trna genes. the origin of replication has been loca ...200312949158
effects of f-strain mycoplasma gallisepticum inoculation at twelve weeks of age on the blood characteristics of commercial egg laying two trials, the effects of an f-strain mycoplasma gallisepticum (fmg) inoculation at 12 wk of age on the blood characteristics of commercial single combed white leghorn laying hens were investigated throughout lay. variables measured in both trials were whole blood hematocrit, plasma protein (pp), and serum cholesterol, triglycerides (st), and calcium. in both trials, hematocrit at 20 wk of age was significantly increased in birds inoculated with fmg. in trial 1, st and pp were significantly ...200312967252
prevalence of infectious diseases in ring-necked pheasant flocks in poland.the health status of ring-necked pheasants in view of the prevalence of infectious diseases was estimated in polish pheasantries in the years 1997-2000. anatomicopathological, microbiological and serological examinations were carried out on birds derived from 26 pheasantries, including birds randomly selected from 18 flocks and sick or dead birds sent from 8 pheasantries. antibodies specific to the following viruses were detected in serum blood samples: he, ae, ap, reo, ai, adeno group 1, md, nd ...200314510048
effects of cyclosporin a on the immune responses and pathogenesis of a virulent strain of mycoplasma gallisepticum in chickens.immune responses to the virulent s6 strain of mycoplasma gallisepticum in immunocompetent and cyclosporin a (csa)-treated specific pathogen free chickens were investigated, and pathogenesis of the m. gallisepticum strain was also examined. ten-day-old specific pathogen free chickens were inoculated by eye-drop with m. gallisepticum, and a control uninfected group was inoculated with mycoplasma broth. blood was collected weekly for 4 weeks from five birds in each group and whole blood lymphocyte ...200314522705
characterization of a naturally occurring infection of a mycoplasma gallisepticum house finch-like strain in turkey outbreak of mycoplasma gallisepticum (mg) in commercial turkeys involving very mild clinical signs was difficult to confirm by routine methods. in the first part of this study (trial a), we conducted a bioassay to increase the likelihood of detecting mg. susceptible turkeys were inoculated with sinus exudates from four different affected commercial turkey flocks. turkeys were evaluated for clinical signs, as well as by serology and culture of tracheal swabs, at 21 and 42 days postchallenge. a ...200314562878
molecular variability of house finch mycoplasma gallisepticum isolates as revealed by sequencing and restriction fragment length polymorphism analysis of the pvpa gene.mycoplasma gallisepticum, a major pathogen of chickens and turkeys, has caused significant declines in house finch (carpodacus mexicanus) populations in the eastern united states since it was first observed in this species in 1994. there is evidence that m. gallisepticum infection is now endemic among eastern house finches, although disease prevalence has declined, suggesting an evolving host-parasite relationship. studies based on randomly amplified polymorphic dna (rapd) have documented the pr ...200314562892
real-time polymerase chain reaction for mycoplasma gallisepticum in chicken this work, we describe a rapid detection procedure for mycoplasma gallisepticum from chicken tracheal swabs by real-time polymerase chain reaction (pcr) by lightcycler system, where we were able to monitor the amplification of the newly synthesized m. gallisepticum-specific pcr product as a proportionally increasing fluorescent signal by using the double-stranded dna binding dye sybr green i and have identified m. gallisepticum-specific pcr products by dna melting curve analysis by plotting t ...200314562901
induction of a mycoplasma gallisepticum pmga gene in the chicken tracheal ring organ culture model.genetic and molecular methods to investigate the pathogenesis of the poultry respiratory pathogen mycoplasma gallisepticum are quite limited. therefore, the objective of this study was to design and evaluate a functional genomics approach to identify m. gallisepticum genes involved in colonization of the poultry respiratory tract. to serve as a transcriptional reporter, a promoterless lacz gene from escherichia coli was cloned into the tn4001 transposon. the transposon was used to randomly mutag ...200314562906
avian influenza (h9n2) outbreak in epidemic of avian influenza (ai) (h9n2) occurred in broiler chicken farms in iran during 1998-01. mortality between 20% and 60% was commonly observed on the affected farms. mixed infections of the influenza virus with other respiratory pathogens, particularly infectious bronchitis virus and mycoplasma gallisepticum, were thought to be responsible for such high mortality, which resulted in great economic losses. clinical signs included swelling of the periorbital tissues and sinuses, typical r ...200314575072
aerosolization of mycoplasma synoviae compared with mycoplasma gallisepticum and enterococcus order to study the airborne transmission of an arthropathic strain of mycoplasma synoviae, preliminary aerosol experiments were performed. they were conducted in duplicate in an empty isolator (1.3 m3) to assess the yield and viability of m. synoviae with time compared with mycoplasma gallisepticum and enterococcus faecalis. after aerosol generation air samples were taken with two different devices using gelatine or cellulose nitrate filters. there was no difference between the devices, but c ...200415276990
morphologic changes in chicken cells after in vitro exposure to mycoplasma gallisepticum.mycoplasma gallisepticum (mg) was used to expose chicken peripheral blood lymphocytes (pbls), red blood cells (rbcs), heterophils, and chicken tumor cells (msb-1 and hd-11 cells). incubation of pbls with mg for 3 hr resulted in extensive clumping of lymphocytes. incubation of the msb-1 cells with mg also caused clumping of the cells, with many of the cells showing perforations and others showing capping of the surface projections. incubation of rbcs with mg resulted in an altered cell surface mo ...200415529970
geneorder3.0: software for comparing the order of genes in pairs of small bacterial increasing number of whole viral and bacterial genomes are being sequenced and deposited in public databases. in parallel to the mounting interest in whole genomes, the number of whole genome analyses software tools is also increasing. geneorder was originally developed to provide an analysis of genes between two genomes, allowing visualization of gene order and synteny comparisons of any small genomes. it was originally developed for comparing virus, mitochondrion and chloroplast genomes. th ...200415128433
experimental infection of house finches with mycoplasma gallisepticum.mycoplasma gallisepticum (mg) has caused an endemic upper respiratory and ocular infection in the eastern house finch (carpodacus mexicanus) after the epidemic first described in 1994. the disease has been studied by a number of investigators at a population level and reports describe experimental infection in group-housed mg-free house finches. because detailed observation and evaluation of individual birds in group-housed passerines is problematic, we studied individually housed house finches ...200415137491
effects of mushroom and herb polysaccharides, as alternatives for an antibiotic, on the cecal microbial ecosystem in broiler in vivo experiment was conducted to study the potential prebiotic effects of mushroom and herb polysaccharide extracts, lentinus edodes extract (lene), tremella fuciformis extract, and astragalus membranaceus radix extract, on chicken growth and the cecal microbial ecosystem, as compared with the antibiotic apramycin (apr). this investigation was carried out in terms of a dose-response study. the chickens were naturally infected with avian mycoplasma gallisepticum prior to the experiment. the ...200414979567
health survey of house finches (carpodacus mexicanus) from wisconsin.we conducted a health survey of house finches (carpodacus mexicanus) without evidence of mycoplasma gallisepticum infection in order to establish baseline population health measures and estimate prevalence of potential pathogens likely to influence host susceptibility to mycoplasmosis. seasonal changes in several physiologic parameters were observed. weights were greater in winter compared with the breeding season (p < 0.01), fat scores were greater in winter than during fall migration (p < 0.01 ...200415077801
safety and efficacy of the avirulent mycoplasma gallisepticum strain k5054 as a live vaccine in poultry.a mycoplasma gallisepticum (mg) isolate from an atypically mild outbreak in turkey breeders was found to be similar to house finch isolates by dna analyses. a preliminary study in turkeys showed that this isolate (k5054) caused very mild lesions and protected turkeys against subsequent challenge with a virulent mg strain. in this study, k5054 was further evaluated as a potential vaccine strain in commercial layer-type chickens and turkeys. the safety of k5054 was evaluated by aerosol challenge f ...200415077802
effects of an s6 strain of mycoplasma gallisepticum inoculation before beginning of lay on the leukocytic characteristics of commercial layers.a clinical study was conducted on commercial layers housed in biological isolation units, within which exogenous stress factors potentially affecting bird performance were minimized. this set-up was devised in order to assess how a pre-lay inoculation of s6 strain mycoplasma gallisepticum affects the leukocytic properties of laying chickens. previous studies have demonstrated relative decreases in lymphocyte and relative increases in heterophil percentages in birds infected with other strains of ...200415077815
mycoplasma gallisepticum--induced alterations in cytokine genes in chicken cells and embryos.mycoplasma gallisepticum (mg) was used to infect the msb-1 cells, the hd-11 cells, and chicken embryos. the rna from these cells and the embryonic spleen cells were extracted and assayed for the expression of cytokine genes using reverse transcription-polymerase chain reaction. the results showed that mg infection suppressed the expression of the il-8 gene in the msb-1 cells and enhanced the expression of the il-8 and il-6 genes in the hd-11 cells; a slightly increased expression of macrophage i ...200415077819
induced expression of the antimicrobial peptide melittin inhibits experimental infection by mycoplasma gallisepticum in chickens.the in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with mycoplasma gallisepticum was studied. the plasmid vector pbi/mel2/rtta includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtta. aerosol administration of the vector, followed by infecting the chickens with m. gallisepticum 1226, is shown t ...200415158186
safety of mycoplasma gallisepticum vaccine strain 6/85 after backpassage in turkeys.the objective of this research was to evaluate the safety of the 6/85 strain vaccine strain of mycoplasma gallisepticum in turkeys by backpassing the vaccine strain up to 10 times by contact infection in turkeys and challenging turkeys with the resulting backpassaged strain. the vaccine strain, however, did not spread to in-contact turkeys, and it was necessary to reisolate the organism before challenging turkeys for the next passage. the challenge strain, therefore, was one that had been backpa ...200415529988
significance of interactions between escherichia coli and respiratory pathogens in layer hen flocks suffering from colibacillosis-associated mortality.this study aimed to examine the significance of interactions between escherichia coli and various respiratory pathogens during outbreaks of colibacillosis-associated mortality in layer hen flocks under field conditions. for this purpose, a case-control study involving 20 control flocks with baseline mortality and 20 flocks with increased mortality due to e. coli septicaemia and polyserositis, was conducted. in each colibacillosis flock, blood samples were taken from 20 hens at the onset of clini ...200415223556
molecular characterization of mycoplasma gallisepticum isolates from turkeys.mycoplasma gallisepticum was isolated from several turkey flocks at different locations in the united states that were clinically affected with respiratory disease. five of these isolates from four series of outbreaks had patterns similar to the 6/85 vaccine strain of m. gallisepticum by random amplified polymorphic dna (rapd) analysis using three different primer sets, whereas with a fourth primer set (opa13 and opa14), only two of the isolates were similar to 6/85. results obtained by sequenci ...200415529978
seasonality and wildlife disease: how seasonal birth, aggregation and variation in immunity affect the dynamics of mycoplasma gallisepticum in house finches.we examine the role of host seasonal breeding, host seasonal social aggregation and partial immunity in affecting wildlife disease dynamics, focusing on the dynamics of house finch conjunctivitis (mycoplasma gallisepticum (mg) in carpodacus mexicanus). this case study of an unmanaged emerging infectious disease provides useful insight into the important role of seasonal factors in driving ongoing disease dynamics. seasonal breeding can force recurrent epidemics through the input of fresh suscept ...200415615682
inactivation, storage, and pcr detection of mycoplasma on fta filter paper.we evaluated the feasibility of using flinders technology associates (fta) filter paper for the inactivation and storage of mycoplasma dna templates and their detection by the polymerase chain reaction (pcr). fta paper is a cotton-based cellulose membrane containing lyophilized chemicals that lyses most types of bacteria and viruses. mycoplasma gallisepticum (mg) and mycoplasma synoviae (ms) cultures were spotted at various volumes on the filter paper and stored at different temperatures for var ...200415666865
effects of mycoplasma gallisepticum on reproductive success in house finches.long known as a pathogen of poultry, mycoplasma gallisepticum (mg) was first detected in house finches in 1994. the disease rapidly spread throughout the eastern united states and canada and was associated with debilitating disease and high mortality in house finches. however, in the late 1990s, the proportion of infected finches dying as a result of infection with mg decreased, and asymptomatic infection was more common among wild birds than in the past. we documented mg infections in breeding ...200415666869
the effect of mycoplasmosis on carotenoid plumage coloration in male house finches.parasites are widely assumed to cause reduced expression of ornamental plumage coloration, but few experimental studies have tested this hypothesis. we captured young male house finches carpodacus mexicanus in alabama before fall molt and randomly divided them into two groups. one group was infected with the bacterial pathogen mycoplasma gallicepticum (mg) and the other group was maintained free of mg infection. all birds were maintained through molt on a diet of seeds with tangerine juice added ...200415143143
disposition kinetics of doxycycline in chickens naturally infected with mycoplasma gallisepticum.1. the pharmacokinetic properties of doxycycline were determined in healthy chickens and chickens naturally infected with mycoplasma gallisepticum after a single intravenous (i.v.) and oral administration of the drug at 20 mg/kg body weight. tissue residues of the tested drug after an oral dose of 20 mg/kg given twice daily for 5 consecutive days were also estimated in diseased chickens. 2. the plasma concentrations of doxycycline following single i.v. and oral administration were higher in heal ...200415484732
testing the efficacy of fermented wheat germ extract against mycoplasma gallisepticum infection of chickens.the effect of fermented wheat germ extract (fwge, immunovet-hbm) was studied in chickens challenged with mycoplasma gallisepticum. ninety m. gallisepticum- and m. synoviae-free 3-wk-old chickens were exposed to aerosol infection of m. gallisepticum. one group (30 birds) was treated with fwge, a second group with tiamulin, and a third group was untreated. the fourth group was exposed to pbs aerosol as a negative control. on d 9, all chickens were slaughtered and examined for the presence of gross ...200415554060
a serological survey for pathogens in old fancy chicken breeds in central and eastern part of the get an impression of the presence of pathogens in multi-aged flocks of old fancy chicken breeds in the netherlands, plasma samples originating from 24 flocks were examined for antibodies against 17 chicken pathogens. these flocks were housed mainly in the centre and east of the netherlands, regions with a high poultry density. the owners of the tested flocks showed their chicken at national and international poultry exhibitions. antibodies against avian influenza, egg drop syndrome '76 virus, ...200415185615
a putative transposase gene in the 16s-23s rrna intergenic spacer region of mycoplasma imitans.examination of the nucleotide sequences of the 16s-23s intergenic transcribed spacer (its) region of mycoplasma imitans and mycoplasma gallisepticum identified a putative transposase gene located only in the its of m. imitans, which can be used as a genetic marker to distinguish these two species. the relative size of the pcr products of the its region allowed a clear distinction to be made between strains of m. imitans and m. gallisepticum, both of which could be readily discriminated from the ...200415073311
molligen, a database dedicated to the comparative genomics of mollicutes.bacteria belonging to the class mollicutes were among the first ones to be selected for complete genome sequencing because of the minimal size of their genomes and their pathogenicity for humans and a broad range of animals and plants. at this time six genome sequences have been publicly released (mycoplasma genitalium, mycoplasma pneumoniae, ureaplasma urealyticum-parvum, mycoplasma pulmonis, mycoplasma penetrans and mycoplasma gallisepticum) and as the number of available mollicute genomes inc ...200414681420
shrinking genomics.two bacteria are featured this month, and both are at the lower end of the genome size scale. the first, mycoplasma gallisepticum, belongs to a group of bacteria that have been studied both as important human and animal pathogens and in the pursuit of understanding the essential functions of a self-replicating minimal cell. the second, nanoarchaeum equitans, is an obligate symbiont that only grows in co-culture with another archaeon. n. equitans seems to be the coelacanth of the microbial world- ...200415035003
carotenoid-based plumage coloration predicts resistance to a novel parasite in the house finch.the hamilton-zuk hypothesis proposes that the bright colours displayed by many species of birds serve as signals of individual resistance to parasites. despite the popularity of this hypothesis, only one previous study has tested whether plumage coloration predicts how individuals respond to a disease challenge. we inoculated 24 male house finches (carpodacus mexicanus) of variable plumage hue with a novel bacterial pathogen, mycoplasma gallicepticum (mg). we found no relationship between plumag ...200515558224
use of molecular diversity of mycoplasma gallisepticum by gene-targeted sequencing (gts) and random amplified polymorphic dna (rapd) analysis for epidemiological studies.a total of 67 mycoplasma gallisepticum field isolates from the usa, israel and australia, and 10 reference strains, were characterized by gene-targeted sequencing (gts) analysis of portions of the putative cytadhesin pvpa gene, the cytadhesin gapa gene, the cytadhesin mgc2 gene, and an uncharacterized hypothetical surface lipoprotein-encoding gene designated genome coding dna sequence (cds) mga_0319. the regions of the surface-protein-encoding genes targeted in this analysis were found to be sta ...200515941996
genetic diversity predicts pathogen resistance and cell-mediated immunocompetence in house finches.evidence is accumulating that genetic variation within individual hosts can influence their susceptibility to pathogens. however, there have been few opportunities to experimentally test this relationship, particularly within outbred populations of non-domestic vertebrates. we performed a standardized pathogen challenge in house finches (carpodacus mexicanus) to test whether multilocus heterozygosity across 12 microsatellite loci predicts resistance to a recently emerged strain of the bacterial ...200517148199
real-time polymerase chain reaction for the qualitative and quantitative detection of mycoplasma gallisepticum.the aim of this study was to evaluate the sensitivity and the detection limit of a real-time polymerase chain reaction (q-pcr) developed for the qualitative and quantitative detection of mycoplasma gallisepticum. no cross-reactivity was observed with dna from other important avian mycoplasmas, including mycoplasma synoviae and mycoplasma meleagridis. however, the q-pcr could not distinguish between m. gallisepticum and mycoplasma imitans. the q-pcr had detection limits 10 to 1000 times lower tha ...200516147572
re-exposure of captive house finches that recovered from mycoplasma gallisepticum infection.fourteen house finches were reinoculated (re-exposed) with 0.05 ml (3.24x10(5) colony forming units/ml) of mycoplasma gallisepticum (mg) in the conjunctival sac of each eye. all birds used in this reinoculation study had recovered from previous infection between 27 and 83 days after inoculation. recovery was based on the absence of clinical signs of conjunctivitis and/ or the inability to detect mg in conjunctival or choanal samples. birds were maintained in individual cages under controlled env ...200516107667
genotyping of mycoplasma gallisepticum and m. synoviae by amplified fragment length polymorphism (aflp) analysis and digitalized random amplified polymorphic dna (rapd) analysis.mycoplasma gallisepticum (mg) and m. synoviae (ms) are the cause of considerable economic losses in the poultry industry. molecular differentiation of avian mycoplasma strains may be helpful in tracing infections and in the evaluation of implemented intervention strategies. amplified fragment length polymorphism (aflp) has shown to be a powerful typing technique but the application for poultry mycoplasma strains is very limited. the aim of this study was to evaluate the reproducibility and discr ...200516236471
an acute inflammatory response alters bone homeostasis, body composition, and the humoral immune response of broiler quantify the effects of an acute phase response in broilers, chicks were injected with 1 mg/kg escherichia coli lipopolysaccharide (lps) at 15 and 23 d. lipopolysaccharide injection increased feed/gain (p = 0.03), increased liver weight (p = 0.09), and decreased tibia calcium (p = 0.05) and breaking strength (p < 0.04) by d 28. in a second experiment, 3 d postinjection of chicks at d 31, lps decreased bw (p < 0.01), breast weight (p = 0.08), and tibia breaking strength (p = 0.05), and increas ...200515844811
stress responses and disease in three wintering house finch (carpodacus mexicanus) populations along a latitudinal laboratory studies, stress hormones have been shown to impair immune functions, and increase susceptibility to diseases. however, the interactions between stress hormones and disease have rarely been studied in free-ranging populations. in this study, we measured concentrations of the avian stress hormone corticosterone across four winter months (december-march) over two years in three eastern north american house finch populations (carpodacus mexicanus) along a latitudinal gradient. because ...200515922346
mycoplasma gallisepticum hemagglutinin v1ha, pyruvate dehydrogenase pdha, lactate dehydrogenase, and elongation factor tu share epitopes with mycoplasma imitans homologues.mycoplasma gallisepticum is a major pathogen of poultry. mycoplasma imitans is genetically and antigenically closely related to m. gallisepticum, but so far, only a few proteins of m. imitans have been identified as sharing epitopes with m. gallisepticum. in this study, we identified three proteins of m. gallisepticum that share with m. imitans epitopes defined by monoclonal antibodies (mabs). mab 9d4 reacted with the 67-kd hemagglutinin v1ha (previously termed pmga) of m. gallisepticum and with ...200516404991
effects of s6-strain mycoplasma gallisepticum inoculation at ten, twenty-two, or forty-five weeks of age on the performance characteristics of commercial egg laying hens.experimental inoculation of commercial laying hens, maintained under controlled conditions, with the s6-strain of mycoplasma gallisepticum (s6mg) at 10 wk of age has previously been shown to affect the lengths and weights of various portions of the reproductive tract without affecting subsequent performance. two trials were conducted to compare the effects of s6mg inoculation at 10 wk of age (prior to lay), 22 wk of age (onset of lay), and 45 wk of age (during lay) on performance characteristics ...200516463961
transfer of maternal immunoglobulins and antibodies to mycoplasma gallisepticum and mycoplasma synoviae to the allantoic and amniotic fluid of chicken embryos.maternal antibodies can protect avian embryos against vertically transmitted pathogens during embryogenesis and also young birds after hatching. in contrast to the well-known transfer of maternal immunoglobulin (ig) g (also termed igy) from the yolk to embryonic blood, information about the transfer of iga, igg and igm from the egg albumen to the extra-embryonic fluids is very limited. in our study, iga, igg and igm to mycoplasma gallisepticum and mycoplasma synoviae were detected in oviduct was ...200516537160
duplex pcr to differentiate between mycoplasma synoviae and mycoplasma gallisepticum on the basis of conserved species-specific sequences of their hemagglutinin genes.we developed a duplex pcr assay targeting the hemagglutinin multigene families, vlha and pmga, of mycoplasma synoviae and mycoplasma gallisepticum, respectively. the assay proved to be specific and sensitive enough to justify its use for the simultaneous detection of the two major avian mycoplasma species from field isolates.200515695715
the vlha loci of mycoplasma synoviae are confined to a restricted region of the genome.mycoplasma synoviae, a major pathogen of poultry, contains a single expressed, full-length vlha gene encoding its haemagglutinin, and a large number of vlha pseudogenes that can be recruited by multiple site-specific recombination events to generate chimaeric variants of the expressed gene. the position and distribution of the vlha pseudogene regions, and their relationship with the expressed gene, have not been investigated. to determine the relationship between these regions, a physical map of ...200515758238
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