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in vitro antimicrobial activities of capuramycin analogues against non-tuberculous mycobacteria.to determine antibacterial activity of capuramycin analogues sq997, sq922, sq641 and rks2244 against several non-tuberculous mycobacteria (ntm).201020952419
localization of mycobacterium avium subspecies paratuberculosis in artificially inoculated milk and colostrum by fractionation.the purpose of the study was to determine the distribution of mycobacterium avium ssp. paratuberculosis (map) across the main milk and colostrum fractions (cream, curd, and whey). raw milk and colostrum were inoculated with 1 of 2 map strains, atcc 19698 or s-23, yielding initial concentrations of 10(6) to 10(7) cfu/ml. after fractionation, for milk as well as for colostrum, 80 to 90% of the recovered map cells were found in the curd fraction and 10 to 20% in the cream fraction. total map colony ...201020855006
high prevalence of viable mycobacterium avium subspecies paratuberculosis in crohn's disease.to examine the detection rate of viable mycobacterium avium subspecies paratuberculosis (map) in patients with inflammatory bowel disease [crohn's disease (cd) and ulcerative colitis (uc)].201020857526
herd management practices and the transmission of johne's disease within infected dairy herds in victoria, australia.a retrospective cohort study involving 137 dairy herds randomly selected from all 390 participating in the victorian test and control program for bovine johne's disease was undertaken to gain insight into the relationships between calf rearing practices and the occurrence of bovine johne's disease on infected dairy farms. each study farm was visited between july 2005 and january 2006 and a structured survey examining herd management and calf rearing practices was completed. the resultant data, a ...201020554069
age at which dairy cattle become mycobacterium avium subsp. paratuberculosis faecal culture positive.age at which cattle become faecal culture positive for mycobacterium avium subsp. paratuberculosis (map) can be used as a proxy parameter for age at onset of faecal shedding, which is an important parameter in the control of map in cattle herds. to investigate the age at becoming faecal culture positive, survival analysis methods were applied. the analyses were carried out on asynchronous interval censored data of faecal culture results of samples collected from 18,979 female holstein-frisian ca ...201020708807
correlation between herrold egg yolk medium culture and real-time quantitative polymerase chain reaction results for mycobacterium avium subspecies paratuberculosis in pooled fecal and environmental samples.real-time quantitative polymerase chain reaction (qpcr) testing for mycobacterium avium subspecies paratuberculosis (map) in fecal samples is a rapid alternative to culture on herrold egg yolk medium (heym), the traditional antemortem reference test for map. although the sensitivity and specificity of these 2 tests have been estimated based on dichotomized test results, the correlation between real-time qpcr threshold cycle (ct) values and colony-forming units (cfu) on heym for fresh and thawed ...201020807920
mycobacterium avium paratuberculosis and the etiology of crohn's disease: a review of the controversy from the clinician's perspective.mycobacterium avium paratuberculosis (map) is an obligate intracellular organism that has frequently been associated with crohn's disease (cd). because cd is a chronic inflammatory condition, many researchers have speculated that an infectious agent must be the cause of cd. map has often been proposed to be one such agent; however, despite considerable research, the evidence remains inconclusive. higher levels of map have been found in the tissues and blood of cd patients than in controls, formi ...201021037992
different mycobacterium avium subsp. paratuberculosis miru-vntr patterns coexist within cattle herds.a better understanding of the biodiversity of mycobacterium avium subsp. paratuberculosis (map) offers more insight in the epidemiology of paratuberculosis and therefore may contribute to the control of the disease. the aim of this study was to investigate the genetic diversity in bovine map isolates using pcr-based methods detecting genetic elements called variable-number tandem repeats (vntrs) and mycobacterial interspersed repetitive units (mirus) to determine if multiple map strains can coex ...201021035277
growth rate retardation and inhibitory effect of para-jem(r) blue on mycobacterium avium subspecies paratuberculosis.the effect of para-jem(r) blue on mycobacterium avium subspecies paratuberculosis (map) inoculated into broth-based culture media was evaluated by using 84 fecal samples with known map status. results showed that growth of the organism in samples inoculated into the broth without the para-jem blue was detectable 1-35 days (average of 6 days) earlier in 35 of the samples (42%) compared with the same samples inoculated in broth with para-jem blue. four additional samples (5%) that were map positiv ...201020807930
primary transcriptomes of mycobacterium avium subsp. paratuberculosis reveal proprietary pathways in tissue and macrophages.mycobacterium avium subsp. paratuberculosis (map) persistently infects intestines and mesenteric lymph nodes leading to a prolonged subclinical disease. the map genome sequence was published in 2005, yet its transcriptional organization in natural infection is unknown. while prior research analyzed regulated gene sets utilizing defined, in vitro stress related or advanced surgical methods with various animal species, we investigated the intracellular lifestyle of map in the intestines and lymph ...201020939887
epitopes of mycobacterium avium ssp. paratuberculosis 70kda heat-shock protein activate bovine helper t cells in outbred cattle.the recombinant 70kda heat-shock protein of mycobacterium avium subspecies paratuberculosis (map hsp70) has been shown to be an immunodominant antigen and a subunit vaccine candidate for bovine paratuberculosis. the aim of the present study was to define map hsp70 specific t cell epitopes in cows immunized with map hsp70 and cows experimentally infected with map. nine peptides were shown to induce proliferation and interferon-gamma production by lymphocytes from map hsp70 immunized cattle. from ...201020600507
veterinarians' perspective on a voluntary johne's disease prevention program in ontario and western canada.a survey was conducted to assess the beliefs of veterinarians on johne's disease (jd) and their attitudes towards the canadian, risk assessment based, jd prevention program. the veterinarians surveyed believed mycobacterium avium subsp. paratuberculosis may have zoonotic potential, liked the risk assessment based program, and thought it could lead to the prevention of other on-farm diseases.201020592831
lack of association between the occurrence of crohn's disease and occupational exposure to dairy and beef cattle herds infected with mycobacterium avium subspecies paratuberculosis.a cross-sectional survey was conducted to identify associations between crohn's disease (cd) and mycobacterium avium ssp. paratuberculosis (map) exposure. a questionnaire was used to collect information on exposure to cattle infected with map, and personal and family history of cd in dairy and beef cattle producers with and without map-infected herds, and in veterinarians who did or did not have contact with map-infected herds. cases of cd were selected from respondents and matched 1:4 with cont ...201020494145
estimated prevalence of mycobacterium avium subspecies paratuberculosis infection in herds of dairy goats in france.a study of the prevalence of mycobacterium avium subspecies paratuberculosis (map) infection in dairy goats was carried out in france, using a serological elisa. one hundred and five herds were randomly selected in different regions, and all the goats aged six months or older (11,847 goats) were sampled. an estimation had previously been made of the accuracy of the elisa, and the rogan-gladen estimator was used to convert apparent prevalence values into estimates of true prevalence values. given ...201020834001
development of an immunocapture-polymerase chain reaction assay using igy to detect mycobacterium avium subsp. paratuberculosis.a diagnostic assay using immunomagnetic separation was developed to capture mycobacterium avium subsp. paratuberculosis (map) from bovine feces by means of igy derived from chicken eggs. the antibody was coupled directly onto the surface of magacell cellulose/iron oxide beads or indirectly by being mixed with magabeads and a rabbit igg linker against chicken antigen. optimization parameters for the immunocapture included incubation time, temperature, volume, and type of immunocapture beads. anal ...201020592839
bayesian estimation of the receiver operating characteristic curve for a diagnostic test with a limit of detection in the absence of a gold standard.the receiver operating characteristic (roc) curve is commonly used for evaluating the discriminatory ability of a biomarker. measurements for a diagnostic test may be subject to an analytic limit of detection leading to immeasurable or unreportable test results. ignoring the scores that are beyond the limit of detection of a test leads to a biased assessment of its discriminatory ability, as reflected by indices such as the associated area under the curve (auc). we propose a bayesian approach fo ...201020603894
peyer's patch-deficient mice demonstrate that mycobacterium avium subsp. paratuberculosis translocates across the mucosal barrier via both m cells and enterocytes but has inefficient dissemination.mycobacterium avium subsp. paratuberculosis, the agent of johne's disease, infects ruminant hosts by translocation through the intestinal mucosa. a number of studies have suggested that m. avium subsp. paratuberculosis interacts with m cells in the peyer's patches of the small intestine. the invasion of the intestinal mucosa by m. avium subsp. paratuberculosis and mycobacterium avium subsp. hominissuis, a pathogen known to interact with intestinal cells, was compared. m. avium subsp. paratubercu ...201020498259
comparison of the activities of the lantibiotics nisin and lacticin 3147 against clinically significant mycobacteria.the aim of this study was to use the microtitre alamarblue assay to investigate and compare the antimycobacterial potential of the lantibiotics nisin and lacticin 3147 against a representative cohort of clinically significant mycobacteria, i.e. mycobacterium tuberculosis h37ra, mycobacterium avium subsp. paratuberculosis (map) atcc 19698 and mycobacterium kansasii cit11/06. lacticin 3147 displayed potent activity against all strains of mycobacteria, with mic(90) values (lowest concentration of l ...201020547041
assessment of food as a source of exposure to mycobacterium avium subspecies paratuberculosis (map).the national advisory committee on microbiological criteria for foods assessed the importance of food as a source of exposure to mycobacterium avium subspecies paratuberculosis (map). map is the causative agent of johne's disease, which affects primarily the small intestine of all ruminants. the significance of map as a human pathogen is unknown and is being investigated by several research groups. this document also reviews the efficacy of current detection methods, processing interventions, an ...201020615354
specific detection of unamplified mycobacterial dna by use of fluorescent semiconductor quantum dots and magnetic beads.here we present the development of a specific dna detection method using fluorescent semiconductor quantum dots (qds) and magnetic beads (mbs) for fast detection of mycobacterium spp., dispensing with the need for dna amplification. two biotinylated oligonucleotide probes were used to recognize and detect specific complementary mycobacterial target dna through a sandwich hybridization reaction. cadmium selenite qds conjugated with streptavidin and species-specific probes were used to produce a f ...201020554817
b-cell epitope specificity of carboxy terminus of mycobacterium paratuberculosis modd.epitope mapping of modd of mycobacterium paratuberculosis was performed using overlapping peptides. in total, 80 overlapping peptides, covering the entire mature modd, were commercially synthesized. each peptide spanned 14 amino acids with an offset of 4 amino acids, i.e., with an overlap of 10 amino acids. synthetic peptide antigenicity was evaluated by enzyme-linked immunosorbent assay (elisa) using rabbit antisera to culture filtrate (cf) of m. avium or m. paratuberculosis or recombinant modd ...201020623405
ovine immune parameters following immunisation against mycobacterium avium ssp. paratuberculosis using a lipid-based live-cell vaccine.current commercial sheep vaccines against mycobacterium avium subspecies paratuberculosis (map) are based on the use of live or killed cells from avirulent map strains. these stimulate a mixed immune response, featuring both antibody-based and cell-mediated immunity, and can only confer partial protection against johne's disease but do not prevent infection. this study aimed to identify immune responses in sheep following immunisation with a novel lipid-based live-cell vaccine, drawing compariso ...201020627411
effect of johne's disease status on reproduction and culling in dairy cattle.among the costs attributed to mycobacterium avium ssp. paratuberculosis (map) infection in dairy cattle, the effects on reproduction and culling are the least documented. to estimate the cost of map infections and johne's disease in a dairy herd, the rates of calving and culling were calculated for cows in each stage of map infection relative to uninfected cows. data from 6 commercial dairy herds, consisting of 2,818 cows with 2,754 calvings and 1,483 cullings, were used for analysis. every cow ...201020655419
presence of mycobacterium avium subsp. paratuberculosis in environmental samples collected on commercial dutch dairy farms.mycobacterium avium subsp. paratuberculosis, the causative agent of johne's disease in cattle, was identified in settled-dust samples of dutch commercial dairy farms, both in the dairy barn and in the young stock housing. bioaerosols may play a role in within-farm m. avium subsp. paratuberculosis transmission.201020656861
absorbed evelisa: a diagnostic test with improved specificity for johne's disease in cattle.the use of enzyme-linked immunosorbent assays (elisas) is recommended for johne's disease (jd) control in dairy herds. in 2006, we developed a novel elisa test for jd, named evelisa (elisa using ethanol extract of mycobacterium avium subsp. paratuberculosis), which showed higher sensitivity than commercial elisa tests. to further investigate the performance of evelisa, we obtained 38 serum samples from cattle in a jd-free herd with suspected cases of serological false-positive reactions. when th ...201020704508
genetic loci involved in antibody response to mycobacterium avium ssp. paratuberculosis in cattle.mycobacterium avium subsp. paratuberculosis (map) causes chronic enteritis in a wide range of animal species. in cattle, map causes a chronic disease called johne's disease, or paratuberculosis, that is not treatable and the efficacy of vaccine control is controversial. the clinical phase of the disease is characterised by diarrhoea, weight loss, drop in milk production and eventually death. susceptibility to map infection is heritable with heritability estimates ranging from 0.06 to 0.10. there ...201020559561
intracellular ph of mycobacterium avium subsp. paratuberculosis following exposure to antimicrobial compounds monitored at the single cell level.mycobacterium avium subsp. paratuberculosis (map) is the etiologic agent of johne's disease; moreover, it seems to be implicated in the development of crohn's disease in humans. in the present study, fluorescence ratio imaging microscopy (frim) was used to assess changes in intracellular ph (ph(i)) of one strain of map after exposure to nisin and neutralized cell-free supernatants (ncss) from five bacteriocin-producing lactic acid bacteria (lab) with known probiotic properties. the evaluation of ...201020573414
inter-laboratory comparison of radiometric culture for mycobacterium avium subsp. paratuberculosis using raw milk from known infected herds and individual dairy cattle in victoria.to compare the results of radiometric culture conducted in three australian laboratories for mycobacterium avium subsp. paratuberculosis (mptb) using bulk vat and individual animal milk samples.201020579029
a principal component regression based genome wide analysis approach reveals the presence of a novel qtl on bta7 for map resistance in holstein cattle.bovine johne's disease (jd), caused by mycobacterium avium spp. paratuberculosis (map), causes significant losses to the dairy and beef cattle industries. effective vaccination or therapeutic strategies against this disease are currently unavailable and infected animals either get culled or die due to clinical disease. an alternative strategy to manage the disease is to selectively breed animals with enhanced resistance to map infection. therefore, the objective of this study was to identify gen ...201020060464
the role of infection in the aetiology of inflammatory bowel disease.we have greatly increased our understanding of the genetics of inflammatory bowel disease (ibd) in the last decade; however, migrant studies highlight the importance of environment in disease risk. the possibility that ibd is an infection has been debated since the first description of crohn's disease. mycobacterium avium paratuberculosis was the first organism to be suggested as an ibd pathogen, and it has been argued that it fulfils koch's postulates and could be designated the cause of crohn' ...201020076977
molecular detection and typing of mycobacterium avium subspecies paratuberculosis from milk samples of dairy animals.genotyping of mycobacterium avium subspecies paratuberculosis (map) is important for precise classification of bacterium and for understanding the molecular epidemiology. the present study reports detection and typing of the map from milk. on the basis of clinical signs of diarrhea and/or weakness, the dairy animals suspected for johne's disease were screened by ziehl-neelsen staining of fecal samples. the milk samples from 13 selected animals were processed for dna extraction and direct is900 p ...201020082257
surveys for disease agents in introduced elk in arkansas and kentucky.surveys for disease agents were conducted in introduced free-ranging elk (cervus elaphus nelsoni) in arkansas and kentucky. elk had been captured in colorado and nebraska and released in arkansas during 1981-1985. from 1997 through 2002 elk were captured in arizona, kansas, north dakota, new mexico, oregon, and utah and released in southeastern kentucky. specimens were collected from 170 hunter-killed elk in arkansas during 1998-2006, and 44 elk in kentucky during 2001-2004. significant findings ...201020090032
comparison of three methods for extraction of mycobacterium avium subspecies paratuberculosis dna for polymerase chain reaction from broth-based culture systems.conventional and real-time polymerase chain reaction (pcr) assays were used to measure the recovery of dna from mycobacterium avium subspecies paratuberculosis (map) extracted with 3 different methods (magmax, dneasy(r), and phenol-chloroform) after growth in a broth-based culture system. of the 304 samples tested, bacterial dna was detected in 197 (65%) of samples after magmax, 156 (51%) after phenol-chloroform, and 123 (40%) after dneasy extractions. by acid-fast stain, 177 (58%) of the sample ...201020093685
partial proteome of mycobacterium avium subsp. paratuberculosis under oxidative and nitrosative stress.the growth pattern and protein expression profiles of sheep (s) and cattle (c) strains of mycobacterium avium subsp. paratuberculosis (map) under oxidative and nitrosative stress were characterised. oxidative stress was induced using 0.05% (v/v) h(2)o(2) in bactec medium, and was lethal for an inoculum of 10(4) cells. however, an inoculum of 10(7) cells survived and proteomic changes were observed at 7 days. nitrosative stress was induced using 1mm nano(2); it slowed the growth of an inoculum of ...201020413229
isolation of mycobacterium avium subspecies paratuberculosis from muscle and peripheral lymph nodes using acid-pepsin digest prior to bactec culture.meat has received little attention regarding human exposure to mycobacterium avium subsp. paratuberculosis, a possible infectious trigger of crohn's disease. meat has less contamination with other organisms than gut tissues, facilitating modifications to existing decontamination protocols prior to bactec culture that could increase analytical sensitivity. using spiked meat samples we trialled enzymatic and chemical digestion techniques to concentrate larger starting samples, and modifications to ...201020363569
is mycobacterium avium subsp. paratuberculosis, the cause of johne's disease in animals, a good candidate for crohn's disease in man?mycobacterium avium subspecies paratuberculosis (map) causes johne's disease or paratuberculosis, a gastro intestinal inflammatory condition in ruminants and other animals, which is similar to crohn's disease (cd) that occurs in man. the role of map in the causation of cd has been under intense investigation in the last few decades. this review summarizes the status of map in animals and the food chain and its association with cd in man.201020443099
proposing a relationship between mycobacterium avium subspecies paratuberculosis infection and hashimoto's thyroiditis.humans are widely exposed to mycobacterium avium subspecies paratuberculosis (map), a proven multi-host chronic enteric pathogen that has recently been linked to autoimmune diabetes. in the present study we used a map species-specific polymerase chain reaction with the insertion element is900-specific probe to detect map infection in members of the same family suffering from hashimoto's thyroiditis.201020429717
crohn's disease and ruminant farming. got lactase?crohn's disease (cd) is a well known chronic pathological condition whose aetiology has remained unrecognized for nearly a century. complex immune mechanisms in a specific genetic background causing an abnormal local inflammatory response are thought to be directly responsible for the clinical picture, but no external factor triggering such host responses has been identified. humans lose the capability of breaking down milk lactose early in life and, afterwards, ingestion of large amounts of lac ...201020451331
identification of single nucleotide polymorphisms in the bovine solute carrier family 11 member 1 (slc11a1) gene and their association with infection by mycobacterium avium subspecies paratuberculosis.johne's disease is a chronic enteritis caused by mycobacterium avium ssp. paratuberculosis (map) that causes substantial financial losses for the cattle industry. susceptibility to map infection is reported to be determined in part by genetic factors, so marker-assisted selection could help to obtain bovine populations that are increasingly resistant to map infection. solute carrier family 11 member 1 (slc11a1) was adjudged to be a potential candidate gene because of its role in innate immunity, ...201020338449
consecutive excretion of mycobacterium avium subspecies paratuberculosis in semen of a breeding bull compared to the distribution in feces, tissue and blood by is900 and f57 quantitative real-time pcr and culture examinations.paratuberculosis (johne's disease) has emerged as one of the most important diseases in cattle. the role of infected bull semen in the spread of infection remains unclear, as the correlation between the amount of excreted mycobacterium avium subsp. paratuberculosis (semen and feces) and the infection load (blood and tissues) has not been defined. the aim of the present study was to study by culture, and a quantitative real-time polymerase chain reaction, the presence of bacteria in consecutive s ...201020460836
assessing virulence of vaccine strains of mycobacterium avium subspecies paratuberculosis in a calf model.the purpose of this investigation was to characterise the virulence of two mycobacterium avium subspecies paratuberculosis (m.a. paratuberculosis) vaccine strains and compare them with a recent virulent isolate in new born calves over a time course of 8 months post-inoculation. paratuberculosis-free new born calves were inoculated orally with either a vaccine strain (2e or 316f) or a wild type strain (f13) of m.a. paratuberculosis. blood and faecal samples were collected throughout the experimen ...201020472374
genetic association between bovine nod2 polymorphisms and infection by mycobacterium avium subsp. paratuberculosis in holstein-friesian cattle.nucleotide-binding oligomerization domain 2 (nod2) has been reported to be a candidate gene for mycobacterium avium subsp. paratuberculosis (map) infection in a bos taurus × bos indicus mixed breed based on a genetic association with the c.2197t>c single nucleotide polymorphism (snp). nevertheless, this snp has also been reported to be monomorphic in the b. taurus species. in the present work, 18 snps spanning the bovine nod2 gene have been analysed in a genetic association study of two independ ...201020477790
a large-scale study of differential gene expression in monocyte-derived macrophages infected with several strains of mycobacterium avium subspecies paratuberculosis.mycobacterium avium subspecies paratuberculosis (map) is a significant concern to the american and european dairy industries and possibly to human health. map possesses the rare ability to survive and replicate in infected macrophages, cells that are typically able to destroy pathogens. little is known about what changes occur in map-infected macrophages that prevent phagosome maturation and lead to intracellular survival of the bacteria. in this study, a bovine immunologically specific cdna mic ...201020495212
gsea-snp identifies genes associated with johne's disease in cattle.snp-based gene-set enrichment analysis from single nucleotide polymorphisms, or gsea-snp, is a tool to identify candidate genes based on enrichment analysis of sets of genes rather than single snp associations. the objective of this study was to identify modest-effect genes associated with mycobacterium avium subsp. paratuberculosis (map) tissue infection or fecal shedding using gsea-snp applied to kegg pathways or gene ontology (go) gene sets. the illumina bovine snp50 beadchip was used to geno ...201020706723
evidence for age susceptibility of cattle to johne's disease.calf rearing programs for the control of bovine johne's disease (bjd) in dairy farms have been widely adopted globally and are based on evidence that the most significant risk factor for developing the disease is exposure of young calves to infectious doses of the causative organism mycobacterium avium subsp. paratuberculosis (mptb). hygienic calf rearing practices aim to break the transmission cycle of mptb by removing neonatal calves from their dams within 12h of birth and segregating replacem ...201019246220
the early lymphocyte proliferation response in sheep exposed to mycobacterium avium subsp. paratuberculosis compared to infection status.johne's disease (jd) is an enteric mycobacterial infection of ruminants that has significant global economic impact. not all individuals exposed to pathogenic mycobacteria succumb to disease. therefore although early detection of infectious individuals is vital, it is equally important to distinguish how the host response differs in those that are able to successfully clear or control mycobacterial infection and those that are unable to do so. to further our understanding of this issue we studie ...201019264377
expression of nramp1 and inos in mycobacterium avium subsp. paratuberculosis naturally infected cattle.paratuberculosis (ptb) is a chronic disease caused by m. avium subsp. paratuberculosis (map) that affects several animal species, and some studies have suggested that there may be a relationship between crohn's disease and ptb. significant aspects of ptb pathogenesis are not yet completely understood, such as the role of macrophages. natural resistance-associated macrophage protein 1 (nramp1) and the inducible nitric oxide synthase (inos) molecules have shown nonspecific effects against several ...201019345998
on the evolution of 'indian bison type' strains of mycobacterium avium subspecies paratuberculosis.mycobacterium avium subspecies paratuberculosis (map), the causative agent of johne's disease (jd) in animals, has also been linked with crohn's disease in human beings. lack of indigenous diagnostics and vaccine hampered control of jd in india. designing effective control strategies require thorough understanding of the etiological agent at phenotypic and molecular levels. on the basis of cultural phenotypes and is1311 pcr-rea typing, map strains have been genotyped as 'cattle type', 'sheep typ ...201019442500
presence, characterization, and genotype profiles of mycobacterium avium subspecies paratuberculosis from unpasteurized individual and pooled milk, commercial pasteurized milk, and milk products in india by culture, pcr, and pcr-rea methods.mycobacterium avium subspecies paratuberculosis (map) causes johne's disease in ruminants, a chronic enteritis evocative of human inflammatory bowel disease. in industrialized countries map has been cultured from pasteurized milk, compounding the increasing concern that map may be zoonotic. the purpose of this study was to evaluate commercially available unpasteurized and pasteurized milk and its products for the presence of viable map or map dna from an area of northern india with a population ...201019576834
the gammadelta cells as marker of non-seroconverted cattle naturally infected with mycobacterium avium subspecies paratuberculosis.early diagnosis of map infection is a pressing need to enable efficient intervention with the spread of map infection in herds. hence, study of lymphocyte subsets and their expressed adhesion molecules could contribute in defining a distinct diagnostic marker (or markers) at the subclinical period of the infection that could in turn facilitate the development of effective diagnostic approach. in accordance with this objective, milk and blood samples were collected from two groups of cattle natur ...201019589549
identification of immune parameters to differentiate disease states among sheep infected with mycobacterium avium subsp. paratuberculosis.johne's disease, a chronic enteritis of ruminants, is caused by infection with mycobacterium avium subsp. paratuberculosis. three distinct forms have been observed in sheep: paucibacillary disease (pb), multibacillary disease (mb), and asymptomatic infection (as). in this study, immune parameters for animals naturally infected with m. avium subsp. paratuberculosis and identified postmortem as having pb, mb, or as were compared to provide a further understanding of the immunological reactivity co ...201019923568
survival of mycobacterium avium subsp. paratuberculosis in biofilms on livestock watering trough materials.mycobacterium avium subsp. paratuberculosis (map) is the causative agent of johne's disease, a chronic enteric infection that affects ruminants. despite the ubiquitous occurrence of mycobacterium sp. in nature and the fact that johne's disease has been reported worldwide, little research has been done to assess its survival in agricultural environments. the goal of this 365-day study was to evaluate the ability of map to persist in mixed-community biofilms on materials commonly used to construct ...201019717251
a mycobacterium avium subsp. paratuberculosis luxr regulates cell envelope and virulence.mycobacterium avium subsp. paratuberculosis adapts to the environment via the regulation of genes affecting its envelope's composition. bacteria grown in milk (in vivo conditions) presented differences in the cell wall-associated lipids and in the expression of genes involved in lipid metabolism (fade8, fade6 and map1420) and host cell invasion (map1203, lprl). a different lipid profile was also observed in the envelope of intracellular bacteria after 1 h of infection. intracellular bacteria sho ...201019710090
the use of mpb70 and mpb83 to distinguish between bovine tuberculosis and paratuberculosis.in order to demonstrate the potential to distinguish paratuberculosis (ptb) from bovine tuberculosis infection (tb), elisas with m. bovis-specific mpb70 or mpb83 as capture antigens were developed and tested on two groups of cattle: group a comprised 23 animals positive for mycobacterium avium paratuberculosis (map) and tb free. group b comprised 48 animals from a map free herd during the previous 5 years, but confirmed as tuberculous by positive results on ppd testing and m. bovis culture. resu ...201019735941
associations between reproductive performance and seropositivity for bovine leukemia virus, bovine viral-diarrhea virus, mycobacterium avium subspecies paratuberculosis, and neospora caninum in canadian dairy cows.our objective was to investigate effects of seropositivity for bovine leukemia virus (blv), type 1 bovine viral-diarrhea virus (bvdv), mycobacterium avium subspecies paratuberculosis (map), and neospora caninum (nc), and their possible interactions, on reproductive efficiency (specifically, first-service conception [fsc], and calving interval [ci]) in dairy cows. the sample population included up to 30 randomly selected animals from 179 randomly selected farms in five provinces in canada, from w ...201020015556
lack of evidence for fecal shedding of mycobacterium avium subsp. paratuberculosis in calves born to fecal culture positive dams.the objective was to detect presence of calves excreting mycobacterium avium subsp. paratuberculosis (map) in their feces as a consequence of being born to map fecal culture positive (vs. negative) dams. for each cow that was about to calf, approximately 10g of feces was collected manually by the herdsmen from the rectum using a disposable plastic examination sleeve within 48-72h prior to actual calving. between 1 and 3d of birth, herd personnel collected approximately 10g of fecal samples follo ...201020015557
age susceptibility of red deer (cervus elaphus) to paratuberculosis.the aim of this study was to measure the relative susceptibility of three age classes of red deer (cervus elaphus) to the various manifestations of infection and disease states due to mycobacterium avium subsp. paratuberculosis (map) after experimental oral challenge. three groups of seronegative female deer (30 three-month-old weaners, 20 fifteen-month-old yearlings and 20 adults) received four oral doses of approximately 10(9) colony forming units (cfu) of a bovine strain of map. they were mon ...201020005645
detection of mycobacterium avium subsp. paratuberculosis in tissue samples of cattle and buffaloes.tissue samples were collected at random from cattle (bos taurus) and buffalo (bubalus bubalis) from an abattoir of the district of lahore and were analyzed for the presence of mycobacterium avium subsp. paratuberculosis and mycobacterium bovis through acid-fast staining and polymerase chain reaction (pcr). body condition of animals and diarrhea were recorded. most of the animals were emaciated. diarrhea was noticed in 15.6% of buffaloes and 19.2% of cattle. intestinal pathology was observed in 2 ...201019816784
molecular identification of mycobacterium avium subspecies paratuberculosis in an italian patient with hashimoto's thyroiditis and melkersson-rosenthal syndrome. 201019797462
a comparison of methods for the construction of confidence interval for relative risk in stratified matched-pair designs.a stratified matched-pair study is often designed for adjusting a confounding effect or effect of different trails/centers/ groups in modern medical studies. the relative risk is one of the most frequently used indices in comparing efficiency of two treatments in clinical trials. in this paper, we propose seven confidence interval estimators for the common relative risk and three simultaneous confidence interval estimators for the relative risks in stratified matched-pair designs. the performanc ...201019856277
identification of seroreactive proteins in the culture filtrate antigen of mycobacterium avium ssp. paratuberculosis human isolates to sera from crohn's disease patients.the etiology of crohn's disease (cd) is unresolved, but it is likely that an interplay of host genetic factors and environmental triggers is relevant. mycobacterium paratuberculosis (map) has been focused upon as one of these triggers because it causes a similar chronic inflammatory bowel disease in animals. however, the differences among map antigens isolated from humans (h-map) and cattle (b-map) have not been well characterized. in this study, culture filtrate (cf) proteins from map isolates ...201019878316
thermal inactivation profiles of mycobacterium avium subsp. paratuberculosis in lamb skeletal muscle homogenate fluid.mycobacterium avium subsp. paratuberculosis (map) causes johne's disease in livestock and there is a debate about its role in humans in chronic inflammatory bowel disorders such as crohn's disease, but the relationship remains unproven. nevertheless livestock health authorities in many countries aim to lower the prevalence of this infection to reduce potential contamination of the human food supply. map may occur in bovine milk and data on thermal inactivation suggest pasteurisation is an effect ...201019896745
mycobacterium avium subsp. paratuberculosis detection in individual and bulk tank milk samples from bovine herds and caprine flocks.paratuberculosis, or johne's disease, is caused by mycobacterium avium subsp. paratuberculosis (map), and it generates great economic losses for the dairy industry worldwide. in humans, map has been associated with crohn's disease. mexico has unknown paratuberculosis prevalence, and yet, control programs have not been applied. this study aimed to determine the presence of map in milk samples from seropositive goats and cows and bulk tank milk samples from herds previously designated map-infected ...201019911881
mycobacterium avium subsp. paratuberculosis in muscle, lymphatic and organ tissues from cows with advanced johne's disease.blood, liver, kidney, lymph nodes and muscle tissue were obtained from the carcasses of five cows with advanced johne's disease. samples from the raw tissues, from cooked muscle tissues and from cooked hamburger patties that contained chopped mesenteric lymph nodes were collected aseptically. each sample was divided into two portions, one of which was decontaminated. both portions were homogenized. homogenates were spread on selective agar for the recovery of mycobacterium avium subsp. paratuber ...201019923028
susceptibility to paratuberculosis infection in cattle is associated with single nucleotide polymorphisms in toll-like receptor 2 which modulate immune responses against mycobacterium avium subspecies paratuberculosis.paratuberculosis is a chronic intestinal infection in ruminants, caused by mycobacterium avium subspecies paratuberculosis (map). to study the role of host genetics in disease susceptibility, the toll-like receptor 2 (tlr2) gene, selected based on its potential role in immunity to mycobacterial infections, was analyzed for single nucleotide polymorphisms (snp) and their potential association with disease. for snp discovery and to study snp association with disease, a case-control study including ...201020005587
a specific induction of interleukin-10 by the map41 recombinant ppe antigen of mycobacterium avium subsp. paratuberculosis.interleukin-10 (il-10) is not only an essential immunoregulator in host immunity, but also it accounts for the intracellular survival of mycobacteria because of its inhibitory activity against anti-mycobacterial functions of macrophage. it has been also indicated that blood cells from calves infected with mycobacterium avium subsp. paratuberculosis (map) produce a large amount of il-10 after stimulation with map antigen, and it leads to suppression of interferon-gamma (ifn-gamma) production in t ...201020018382
experimental infection model for johne's disease using a lyophilised, pure culture, seedstock of mycobacterium avium subspecies paratuberculosis.johne's disease is a severe chronic enteritis of ruminants caused by mycobacterium avium subspecies paratuberculosis (map). repeatable infections of known duration are required for validation of new diagnostic tests, evaluation of pathogenesis and development of improved vaccines. in the first study of its type, a standardised experimental model for johne's disease was developed based on a lyophilised, low passage, pure culture, seedstock of map. experimental inoculations of sheep with accuratel ...201019815353
mycobacterium avium subsp. paratuberculosis (map) as a modifying factor in crohn's disease.crohn's disease (cd) is a multifactorial syndrome with genetic and environmental contributions. mycobacterium avium subspecies paratuberculosis (map) has been frequently isolated from mucosal tissues of patients with cd but the cellular immune response to this bacterium has been poorly described. our aim was to examine the influence of map on t-cell proliferation and cytokine responses in patients with inflammatory bowel disease (ibd).201019824071
reduced transcript stabilization restricts tnf-alpha expression in raw264.7 macrophages infected with pathogenic mycobacteria: evidence for an involvement of lipomannan.despite the critical role that tnf-alpha plays in the containment of mycobacterial infection, the mechanisms involved in regulation of its expression by mycobacteria are poorly defined. we addressed this question by studying map, which causes a chronic enteritis in ruminants and is linked to human crohn's disease. we found that in map infected macrophages, tnf-alpha gene expression was substantially lower than in macrophages infected with nonpathogenic ms or stimulated with lps. tnf-alpha transc ...201019850884
optimisation of culture of mycobacterium avium subspecies paratuberculosis from blood samples.mycobacterium avium subspecies paratuberculosis (map) is the causative agent of johne's disease or paratuberculosis, a chronic enteritis of ruminants, and has been suggested to play a role in crohn's disease in humans. while disease expression is primarily in the gastrointestinal tract, isolation of map or map dna at distant sites indicates that disseminated infections also occur. this is the first study to compare, optimise and critically evaluate different methods of concentrating map from spi ...201019932719
an economic decision support tool for simulating paratuberculosis control strategies in a uk suckler beef herd.a dynamic, deterministic, economic simulation model was developed to estimate the costs and benefits of controlling mycobacterium avium subsp. paratuberculosis (johne's disease) in a suckler beef herd. the model is intended as a demonstration tool for veterinarians to use with farmers. the model design process involved user consultation and participation and the model is freely accessible on a dedicated website. the 'user-friendly' model interface allows the input of key assumptions and farm spe ...201020004032
detection of spatial and temporal spread of mycobacterium avium subsp. paratuberculosis in the environment of a cattle farm through bio-aerosols.environmental samples were collected to investigate the spatial and temporal spread of mycobacterium avium subsp. paratuberculosis (map) in a dairy cattle barn before and after the introduction of two groups of map-shedding animals. samples collected off the floor of the barn reflected the moment of sampling whereas samples collected by microfiber wipes at a minimal of 3m height contained the accumulated settled dust over a 3-week period. samples were analysed by is900 qpcr for the presence of m ...201020036081
assessment of live candidate vaccines for paratuberculosis in animal models and macrophages.mycobacterium avium subsp. paratuberculosis (basonym m. paratuberculosis) is the causative agent of paratuberculosis, a chronic enteritis of ruminants. to control the considerable economic effect that paratuberculosis has on the livestock industry, a vaccine that induces protection with minimal side effects is required. we employed transposon mutagenesis and allelic exchange to develop three potential vaccine candidates, which were then tested for virulence with macrophages, mice, and goats. all ...201020038535
a bayesian weibull survival model for time to infection data measured with delay.survival analysis methods can be used to identify factors associated with the time to induction of infection. in the absence of a perfect test, detection of infection is generally delayed and depends on the duration of the latent infection period. we assess, via simulations, the impact of ignoring the delayed detection of infection on estimated survival times and propose a bayesian weibull regression model, which adjusts for the delayed detection of infection. the presence of non-differential de ...201020129683
sensitivity, specificity, and confounding factors of novel serological tests used for the rapid diagnosis of bovine tuberculosis in farmed red deer (cervus elaphus).in this study, novel serological tests were used to detect tuberculosis (tb) in groups of farmed red deer (cervus elaphus) varying in disease status or possible confounding factors. groups of deer naturally or experimentally infected with mycobacterium bovis and animals vaccinated against paratuberculosis were studied, as were uninfected animals and animals naturally or experimentally infected with mycobacterium avium subsp. paratuberculosis. sera were assayed using two rapid lateral-flow tests, ...201020164247
association between mycobacterium avium subspecies paratuberculosis infection and milk production in two california dairies.the association between mycobacterium avium ssp. paratuberculosis (map) and milk production was estimated on 2 california dairies using longitudinal data from 5,926 cows. both study herds had moderate map seroprevalence, housed cows in freestalls, and had johne's disease control programs. cow map status was determined using both serum elisa and fecal culture results from cows tested at dry-off and from whole-herd tests. potential confounders were evaluated based on a causal diagram. mixed models ...201020172223
culture-independent techniques applied to food industry water surveillance--a case study.culture-independent techniques were used for the detection of pathogenic bacteria in drinking water at potentially critical control points along the production lines at a german dairy company and a spanish dry cured ham company. denaturing gradient gel electrophoresis (dgge) was used to describe bacterial population shifts indicating biological instability in the drinking water samples. autochthonous bacteria were identified by sequencing the excised dgge dna bands. more specifically, real-time ...201020363042
bacterial flora in inflammatory bowel disease.the pathogenesis of inflammatory bowel disease (ibd) involves an interaction between host susceptibility (which is partly genetically determined), mucosal immunity and the intestinal milieu. micro-organisms have physiological effects on mucosal structure, epithelial turnover, the intestinal immune cells and, thus, on many intestinal functions. toll-like receptors and nucleotide oligomerisation-binding domain proteins in host cells recognise specific bacterial molecules and modify the immune resp ...201020203504
optimization of a whole blood gamma interferon assay for the detection of sheep infected with mycobacterium avium subspecies paratuberculosis.the capacity of a commercially available gamma interferon (ifngamma) assay to detect infected sheep early in the pathogenesis of johne's disease enables the removal of such animals from the flock before bacterial shedding and pasture contamination. however, nonspecific ifngamma responses in the assay have meant that to achieve high-test specificity, there has been a reduction in sensitivity. although the optimal conditions for the use of the assay in cattle have been well documented, there have ...201020224078
rapid assessment of the viability of mycobacterium avium subsp. paratuberculosis cells after heat treatment, using an optimized phage amplification assay.thermal inactivation experiments were carried out to assess the utility of a recently optimized phage amplification assay to accurately enumerate viable mycobacterium avium subsp. paratuberculosis cells in milk. ultra-heat-treated (uht) whole milk was spiked with large numbers of m. avium subsp. paratuberculosis organisms (10(6) to 10(7) cfu/ml) and dispensed in 100-microl aliquots in thin-walled 200-microl pcr tubes. a primus 96 advanced thermal cycler (peqlab, erlangen, germany) was used to ac ...201020097817
attitudes towards biosecurity practices relevant to johne's disease control on beef cattle farms.the success of control programs can be improved when producers' attitudes towards these programs are positive. implementation of control programs for chronic diseases are more challenging than those for acute diseases because of the absence of the "cues-to-action" that are associated with acute diseases. johne's disease (jd) is a chronic diarrheal disease of ruminants, and national voluntary control programs exist in several countries. we used a mailed cross-sectional survey to describe the atti ...201020102783
absence of mycobacterium avium ss paratuberculosis-specific is900 sequence in intestinal biopsy tissues of indian patients with crohn's disease.the role of mycobacterium avium ss paratuberculosis (map) in the etiopathology of crohn's disease (cd) remains controversial, because of conflicting reports demonstrating the presence of map-specific insertion sequence from intestinal biopsy tissues of patients clinically diagnosed for the disease. the present study was carried out to investigate the presence of map dna in the intestinal tissues of cd patients to ascertain the relevance of map in indian patients with cd.201020107965
molecular characterization of mycobacterium avium subspecies paratuberculosis types ii and iii isolates by a combination of miru-vntr loci.mycobacterial interspersed repetitive units and variable number tandem repeats typing (miru-vntr) is a useful technique that has been recently applied to characterize members of the mycobacterium avium complex (mac). the aim of this study was to examine the genetic variability among a collection of spanish m. avium subspecies paratuberculosis (m. a. paratuberculosis) isolates with a combination of miru-vntr loci. for this purpose we tested six miru-vntr loci (miru-2, miru-3, vntr-25, vntr-32, vn ...201020116185
rapid identification and differentiation of mycobacterium avium subspecies paratuberculosis types by use of real-time pcr and high-resolution melt analysis of the map1506 locus.high-resolution melt (hrm) analysis can identify sequence polymorphisms by comparing the melting curves of amplicons generated by real-time pcr amplification. we describe the application of this technique to identify mycobacterium avium subspecies paratuberculosis types i, ii, and iii. the hrm approach was based on type-specific nucleotide sequences in map1506, a member of the ppe (proline-proline-glutamic acid) gene family.201020129970
prevalence of mycobacterium avium subsp. paratuberculosis infection in adult danish non-dairy cattle sampled at slaughter.a voluntary, risk-based control program for paratuberculosis in dairy herds was started in 2006 in denmark. the program does not include non-dairy herds, and the occurrence of mycobacterium avium subsp. paratuberculosis (map) in these herds is unknown. the objective of this study was to establish the prevalence of map infected adult non-dairy cattle in denmark. serum samples were collected between october, 2008 and january, 2009 from every 6th animal over 24 months of age, sent to slaughter to d ...201020153536
paradigm redux--mycobacterium avium subspecies paratuberculosis-macrophage interactions show clear variations between bovine and human physiological body temperatures.the physiological conditions encountered by pathogenic mycobacteria inside their hosts significantly influence their adaptation, virulence, and gene expression. current in vitro models investigating host-pathogen interactions of mycobacterium avium subsp. paratuberculosis use 37 degrees c, the normal body temperatures of mice and humans. however since the physiological temperature of map's natural host is 39 degrees c, we hypothesized that host and pathogen behavior to vary considerably in compa ...201020188816
effect of changes in testing parameters on the cost-effectiveness of two pooled test methods to classify infection status of animals in a herd.monte carlo simulation was used to determine optimal fecal pool sizes for identification of all mycobacterium avium subsp. paratuberculosis (map)-infected cows in a dairy herd. two pooling protocols were compared: a halving protocol involving a single retest of negative pools followed by halving of positive pools and a simple protocol involving single retest of negative pools but no halving of positive pools. for both protocols, all component samples in positive pools were then tested individual ...201020207038
investigation of the association of the slc11a1 gene with resistance/sensitivity of goats (capra hircus) to paratuberculosis.slc11a1 (solute carrier family 11 member a1) protein is located on the phagolysosome membrane of macrophages and participates in bacterial killing. here we have extended our previous work on the investigation of the potential association of polymorphisms of the 3'untranslated region (utr) of slc11a1 gene with test-positivity of goats to mycobacterium avium subsp. paratuberculosis (map). blood, serum and faeces were collected from 223 adult goats, from nine goat farms from greece with a long-term ...201020188496
experimental validation of a nested polymerase chain reaction targeting the genetic element ismap02 for detection of mycobacterium avium subspecies paratuberculosis in bovine colostrum.colostrum samples experimentally inoculated with mycobacterium avium subsp. paratuberculosis (map; strain k-10) at increasing concentrations between 1 x 10(1) and 1 x 10(9) cells/ml were tested for recovery of map dna using a nested ismap02 target polymerase chain reaction initially developed for detecting map dna in fecal samples. the following detection rates were achieved for sample replicates inoculated with unsonicated map pure stock: 100% between 1 x 10(7) and 1 x 10(9) cells/ml, 75% betwe ...201020224087
estimation of sensitivity and flock-sensitivity of pooled faecal culture for mycobacterium avium subsp. paratuberculosis in sheep.pooled faecal culture (pfc) is a widely used test in ovine johne's disease (ojd) control programmes in australia but information about its characteristics is limited. we conducted this study to estimate sensitivity and flock-sensitivity of pfc in sheep with different ojd histopathological lesions in simulated flocks with a range of infection prevalence levels. initially, a known quantity of faeces from sheep with pauci- or multibacillary lesions was pooled with uncontaminated faeces from confirm ...201020430455
evaluation of the cell-mediated immune response to reduced doses of mycobacterium avium ssp. paratuberculosis vaccine in cattle.vaccination against johne's disease with an inactivated, oil-adjuvanted mycobacterium avium ssp. paratuberculosis (map) bacterin can reduce clinical signs in infected herds; however, the development of indurated swelling at the injection site limits vaccine acceptability to producers. this study determined whether a reduced dose of vaccine antigen, with a full dose of adjuvant, would produce comparable t cell-mediated immune responses with smaller lesions. t cell responses induced by in vitro st ...201020193967
successful control of johne's disease in nine dairy herds: results of a six-year field trial.the objective was to evaluate if a standardized johne's disease control program significantly reduced the prevalence of cattle infected with mycobacterium avium ssp. paratuberculosis in dairy herds with a moderate to high initial infection prevalence of >or=10% elisa-positive adult cattle. nine wisconsin dairy herds of diverse sizes and management styles completed the 6-yr study. the control program involved changes to heifer rearing practices in combination with a routine testing program. for h ...201020338441
map in the environment of dairy herds - a comment. 201020357935
strain diversity within mycobacterium avium subspecies paratuberculosis--a review.mycobacterium avium subspecies paratuberculosis (map), is the etiological agent of johne's disease (or paratuberculosis) in animals and has also been linked with crohn's disease of human beings. extreme fastidious nature of the organism (map) has hampered studies on diversity within the organism. studies based on phenotypic properties like growth rate, pigmentation, lipid profile etc., are unable to provide complete information on diversity of map organism in nature. however, with the advent of ...201020358861
mycobacterium avium subsp. paratuberculosis viability determination using f57 quantitative pcr in combination with propidium monoazide treatment.mycobacterium avium subsp. paratuberculosis (map) is known to be a very slow-growing organism. the fact that cells typically need several weeks to form visible colonies severely compromises the suitability of plate counting for assessment of viable cell counts. this problem might be overcome by the application of fast molecular methods containing a viability component. we have evaluated a promising technology combining sample treatment with propidium monoazide (pma) prior to dna extraction for s ...201020385417
characteristics of an extensive mycobacterium avium subspecies paratuberculosis recombinant protein set.in the first step of a comprehensive large-scale antigen discovery project, 651 genes of mycobacterium avium subspecies paratuberculosis were expressed in escherichia coli. all of these were purified by affinity chromatography, dialyzed in phosphate buffered saline, and analyzed on sds-page gels. collectively, these purified recombinant proteins represent 14.9% of the total m. avium subsp. paratuberculosis proteome. this volume of protein expression and purification has yielded unique observatio ...201020359537
a survey to detect the presence of mycobacterium avium subspecies paratuberculosis in kangaroo island macropods.the aim of this study was to determine whether mycobacterium avium subspecies paratuberculosis (m. a. paratuberculosis) infection was present in macropods grazing with infected sheep on kangaroo island in 2001-2002, and to assess the likely role of such infection in the epidemiology of ovine paratuberculosis. ileum and associated lymphatics from 482 macropods were examined using radiometric culture followed by pcr for is900 and restriction endonuclease analysis (rea) for species identification, ...201020400245
effect of classifying disease states in genetic association studies for paratuberculosis.genetic association studies are a means to elucidate underlying genetic regulation of host-pathogen interaction, immune response, and the fate of infection. diseases such as paratuberculosis in cattle lack definitive diagnostic criteria, thereby complicating the definition of infection status as an outcome for genetic association studies. a study was performed to evaluate the potential bias in estimates of effect and differences in statistical power associated with parallel test interpretation, ...201020363040
genetic parameters of milk elisa scores for johne's disease.the objective of this study was to estimate genetic parameters of antibody response to mycobacterium avium ssp. paratuberculosis using routinely collected minnesota dairy herd improvement milk elisa tests. after all edits, 25,809 tests from 21,514 holstein cows in 282 johne's positive herds were available for analysis. the johne's test results were analyzed both as a binary trait (positive or negative) and as a linear trait as the transformed elisa optical density [ln(od)]. significant fixed eff ...201020338451
stochastic simulations of a multi-group compartmental model for johne's disease on us dairy herds with test-based culling intervention.infection elimination may be an important goal of control programs. only in stochastic infection models can true infection elimination be observed as a fadeout. the phenomena of fadeout and variable prevalence are important in understanding the transmission dynamics of infectious diseases and these phenomena are essential to evaluate the effectiveness of control measures. to investigate the stochastic dynamics of mycobacterium avium subsp. paratuberculosis (map) infection on us dairy herds with ...201020347851
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