Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “paratuberculosis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources
PubMed2002

[Paratuberculosis eradication programs in Northrhine-Westfalia].

Since 1993 a voluntary eradication program for bovine paratuberculosis is established in Northrhine-Westfalia. After an effectivity control of the serological diagnostics it is combined with the fecal culture since August of 2000. Parallel use of both methods is necessary for a successful eradication. It could be monitored that a high percentage of the newly bought cattle in the herds participating in the eradication program was considered positive. Since paratuberculosis eradication is time and cost extensive besides intensive eradication programs the spread of the disease must be stopped.

Animals↗
PubMed2004

[Considerations concerning diagnostic certainties and cut-off values for a bulk milk ELISA for Mycobacterium avium ssp. paratuberculosis].

Serological tests for the examination of individual samples from single animals are evaluated based on their ability to detect true positives above a defined threshold value. If results are obtained not from an individual but from a bulk sample this concept usually is adopted such that the threshold is set to allow the detection of a single positive sample within the pool. In conjunction with the development of a diagnostic paratuberculosis ELISA for the examination of bulk milk samples it is discussed which interpolations of this concept are justified when defining the true status of a herd based on the test parameters and the seroprevalence within the herd. Here, bulk milk from up to 50 animals each and the corresponding individual samples of 4241 dairy cows from 28 herds in the state of Brandenburg are investigated, and results are subjected to different evaluation approaches. Based on epidemiological considerations and test parameters a "critical prevalence" is defined which then serves as basis for the deduction of a cut-off value to be used for bulk milk samples. Finally, the practical relevance of this approach is demonstrated by suggesting an initial scheme for paratuberculosis classification of dairy herds with respect to possible control measures.

Animals↗
PubMed2004

Susceptibility of Mycobacterium avium sbsp paratuberculosis to monensin sodium or tilmicosin phosphate in vitro and resulting infectivity in a murine model.

This study was designed to determine the susceptibility in vitro and infectivity of 1 field isolate of Mycobacterium avium sbsp paratuberculosis after exposure to monensin sodium and tilmicosin phosphate. Minimum inhibitory concentrations (0.39 microg monensin sodium/mL; 1.60 microg tilmicosin phosphate/mL) were determined in quintuplicate. Organisms were then incubated with 3 different concentrations of each medication for 3 different lengths of time, then washed and resuspended in sterile physiologic saline and injected intraperitoneally into mice that were genetically susceptible to infection. Mice were euthanatized 50 d later and the number of hepatic granulomas was used as the indicator of infectivity. Neither time of incubation nor concentration of medication had any effect on the infectivity of the organisms. Monensin sodium significantly reduced the number of hepatic granulomas in genetically susceptible mice while tilmicosin phosphate did not. Antimycobacterial activity of monensin sodium suggests that the role of monensin in the control of bovine paratuberculosis should be evaluated further.

Animals↗
PubMedDate not supplied

Intracellular invasion and persistence: survival strategies of Streptococcus suis and Mycobacterium avium ssp. paratuberculosis.

Streptococcus (S.) suis and Mycobacterium avium ssp. paratuberculosis (MAP) differ substantially in their host specificity and tissue tropism. S. suis is a facultative pathogen in swine, which mainly colonises the upper respiratory tract and can cause meningitis, septicemia, arthritis and pneumonia. In contrast, MAP is an obligatory pathogen causing paratuberculosis in ruminants, and shows high tropism for the intestinal tract. Both pathogens are able to invade and persist in host cells. In S. suis, the significance of invasion for pathogenesis is a matter of controversial discussions. In vitro it has been shown that S. suis is internalized by epithelial cells and survives intracellularly for at least 24 h. However, at present there is no evidence that S. suis invades epithelial cells also in vivo. In MAP, on the other hand, persistence in macrophages is generally considered a crucial step in pathogenesis, but it remains to be elucidated, how it contributes to pathophysiology of the disease. The two pathogens exemplify how intracellular invasion and persistence might play different roles in pathogenesis. In S. suis, intracellular life may represent only a transient retreat phase, whereas in MAP it is the predominant in vivo niche of the pathogen.

Animals↗
PubMed1992

Effects of mycobactin J and lactoferrin supplementation of drinking water on the in vivo multiplication of Mycobacterium paratuberculosis in gnotobiotic mice.

In this study the effect of supplementation of drinking water with mycobactin J or lactoferrin on the multiplication of Mycobacterium paratuberculosis in gnotobiotic mice was investigated. The results indicated that neither mycobactin J nor lactoferrin, at the doses used, appeared to have any effect on fecal shedding or tissue burdens of M. paratuberculosis.

Administration, Oral↗
PubMedDate not supplied

[From farm to fork--Mycobacterium avium ssp. paratuberculosis (MAP) as zoonotic agent?].

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of the paratuberculosis (Para Tb) in ruminants. In addition, this pathogen has been suspected to be implicated in the pathogenesis of Morbus Crohn disease (MC), causing chronic inflammatory intestine changes of humans. The participation of MAP in this illness is discussed intensively and has very contradictory opinions. On the one hand several times succeeded in proving MAP DNA in changed human tissues as well as, in recent time, the bacteria has been isolated from patient's blood. On the other hand there are many publications which support the opposite opinion. In critical evaluation of already available data, therefore the hypothesis can be formulated that MAP could possibly take part in the MC of humans. The reliable verification of this hypothesis will only be possible, if the diagnostic procedures can be refined upon the substantial deficit concerning the sensitivity and/or specificity of the diagnostic methods. In addition, till now there is lack of optimized statistically case control studies. The conceivable transmission of the bacteria to humans by the direct animal contact has been considered as possible vector, furthermore, MAP has been detected in pasteurised milk and other food of animal origin. The prevalence data, usually estimated by ELISA for milk cattle stock show over 80% prevalence in many counties of the Federal Republic of Germany with an individual case prevalence ranging between 1% and 17% in different stocks. Comparable data are present also from other countries as well as for small ruminants. MAP has been concerned as a global problem, moreover the high spreading rate of MAP in wild animal populations as well as the considerable ability of the bacteria to survive in different stages of the infectious- and contamination-cycle, which might hardly be broken through. Thus it requires intensive research efforts for the development of the methodical diagnostic process as basis for valid epidemiological investigations of animals, humans and food.

Animals↗
PubMed2005

Molecular typing of Mycobacterium avium subspecies paratuberculosis strains from different hosts and regions.

The IS1311 polymerase chain reaction-restriction endonuclease analysis was used to detect genetic differences among 38 Mycobacterium avium subsp. paratuberculosis (Map) isolates from cattle, sheep, goats and bison from distinct regions of Spain, India and the United States of America (USA). In Spain, all eight bovine isolates, three out of six caprine isolates and one of ten ovine isolates were of the C type, while the other nine ovine isolates and three caprine isolates were of the S type. In India, all five ovine isolates and six caprine isolates were of the B type, and so were all three isolates from bison (Bison bison) from the USA. These results show that there are genetic differences between Map isolates related to geographic and host factors that have a potential use in the epidemiological tracing of new paratuberculosis isolates.

Animals↗
PubMed1991

Associations between dairy production indices and lipoarabinomannan enzyme-immunoassay results for paratuberculosis.

Data from an epidemiological study in Ontario, involving 304 dairy herds, were used to identify associations between selected production indices and lipoarabinomannan antigen serological test results for paratuberculosis (LAM-ELISA). Analyses were conducted at both the herd and individual cow levels of organization. After analytically controlling for management and cow factors in the respective regression models, positive serological paratuberculosis status (as defined by the LAM-ELISA test), was associated with higher milk somatic cell counts at both the herd average (p less than 0.01), and individual cow levels of organization (p less than 0.0001). In contrast, LAM-ELISA test results were consistently not associated with calving intervals in either the herd average or individual cow level analyses. Associations between LAM-ELISA results and milk production were inconsistent. No associations were found at the herd level of organization, and LAM-ELISA results were not associated with a change in breed class average (BCA) for milk, between the previous and the most recent lactations of individual cattle. However, at the individual cow level, LAM-ELISA results were positively associated with higher milk production as measured by the current BCA (p less than 0.05), and individual cow average kg of milk produced per year of life since two years of age (p less than 0.0001).

Animals↗
PubMed1994

Mycobacterium paratuberculosis infection in two llamas.

Mycobacterium paratuberculosis was diagnosed in 2 llamas by bacteriologic culturing and DNA probe testing of fecal and intestinal specimens. Diarrhea and weight loss were observed in both animals. Lesions in the gastrointestinal tracts of the 2 llamas were similar to pathologic changes reported in cattle infected with M paratuberculosis.

Animals↗
PubMed1994

Herd prevalence and geographic distribution of, and risk factors for, bovine paratuberculosis in Wisconsin.

A random sample of Wisconsin dairy herds, stratified by herd size, were tested for paratuberculosis by use of an absorbed ELISA procedure. The ELISA was optimized for overall accuracy by means of receiver operating characteristic curve analysis, and had a sensitivity and specificity of 50.9 and 94.9%, respectively. Herd prevalence was analyzed for correlation with responses to a management practices questionnaire completed by the herd owners. One hundred and fifty-eight herds and 4,990 cattle were tested. Of these, 50% of herds and 7.29% of cattle had positive test results. Calculation of true prevalence from the apparent prevalence indicated that 4.79% of cattle and 34% of the Wisconsin dairy herds tested had serologic evidence of paratuberculosis. Among the 54 herds classified as positive on the basis of true prevalence estimation, the mean number of test positive cattle was 20.3%. The geographic distribution of herds with positive results was not uniform. More infected herds were found in the southern and western districts of Wisconsin than in the eastern district. The west-central district had a larger number of infected herds than did other districts. By use of chi 2 analysis, the only management factor found to be significantly associated with herd prevalence was housing of calves after weaning (P = 0.03). Specifically, in herds with higher prevalence, calves were separated after weaning into calf barns and hutches rather than into pens in the cow barn more often than in herds with lower prevalence. This factor was also considered significant by use of logistic regression analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Husbandry↗
PubMed1996

Comparison of milk with serum ELISA for the detection of paratuberculosis in dairy cows.

OBJECTIVE: To compare milk with serum ELISA for detection of antibodies to Mycobacterium paratuberculosis. DESIGN: Epidemiologic survey. ANIMALS: 821 Missouri dairy cattle of 12 herds that were brucellosis certified and Dairy Herd Improvement Association members. PROCEDURE: Milk and serum samples obtained concurrently from Missouri dairy herds were tested by use of a standard ELISA procedure. Concurrent collection of milk and serum samples controlled for interactions such as colostral antibodies and the effect of time. On the basis of milk and serum ELISA values, disease prevalence and correlation between milk and serum test results were determined. RESULTS: Correlation measures on individual animals indicated low correlation of milk and serum ELISA values. McNemar's chi 2 of 7.6 was significant (P = 0.05). Analysis correlation was low (kappa = 0.08), as was regression analysis (R2 = 0.02). CLINICAL IMPLICATIONS: Milk ELISA for the detection of exposure to M paratuberculosis lacked correlation with serum ELISA. Further evaluation to determine sensitivity and specificity of milk ELISA will augment the usefulness of milk ELISA as a herd screening test.

Animals↗
PubMed1995

Isolation of Mycobacterium paratuberculosis from colostrum and milk of subclinically infected cows.

Mycobacterial culture was performed on colostrum, milk, and feces from 126 clinically normal cows of a single herd with high prevalence of Mycobacterium paratuberculosis infection. Thirty-six (28.6%) cows were determined to be shedding the organism in the feces. Of the 36 fecal Culture positive cows, M paratuberculosis was isolated from the colostrum of 8 (22.2%) and from the milk of 3 (8.3%). Cows that were heavy fecal shedders were more likely to shed the organism in the colostrum than were light fecal shedders.

Animals↗
PubMedDate not supplied

Use of an experimental chicks model for paratuberculosis enteritis (Johne's disease).

Developments in the diagnosis and treatment of paratuberculosis is constrained by the lack of an experimental animal model. To investigate this problem conventional chicks immunodepressed by a Cyclophosphamide injection and concurrent inoculation of Infectious Bursal Disease Virus (IBDV) were infected with Mycobacterium paratuberculosis and kept for 4 months. The immunodepressed chicks eliminated mycobacteria with their faces from the first month until the third month and developed typical intestinal lesions of mycobacterial infection characterized by aggregation of macrophages with monocytes and lymphocytes. Diarrhoea was absent. The number of lymphocytes decreased by about 80%. The serological tests carried out with Complement Fixation test were negative. For the positive bacteriology and typical granulomatous lesions, the conventionally reared chicks proved to be a useful laboratory model for reproduction of Johne's disease.

Animals↗
PubMed1999

Relation between pathologic findings and cellular immune responses in sheep with naturally acquired paratuberculosis.

OBJECTIVE: To investigate the relation between lesions and cellular immune response-based tests in sheep with naturally acquired paratuberculosis and to evaluate efficacy of an interferon-gamma (IFN-gamma) assay and the intradermal skin test. ANIMALS: 110 and 88 adult sheep were used to evaluate the IFN-gamma assay and skin test, respectively. PROCEDURE: Before euthanasia, heparinized blood was collected and incubated with avian purified protein derivative (PPD). Interferon-y production was assessed, using a commercial enzyme immunoassay. Skin testing in the caudal fold also was performed, using avian PPD. Sensitivity and specificity of these techniques were evaluated, using histopathologic findings as reference. RESULTS: Of the sheep examined, 61 (55.4%) had lesions that were classified in 5 categories, according to location, extension, cellular types, and presence of acid-fast bacilli. Regarding cellular immunity test results, 55.4% of sheep with and 6.1 % without pathologic changes had positive results of the IFN-gamma assay. Skin test sensitivity (55.6%) and specificity (100%) were slightly greater. CONCLUSION: Close association between pathologic findings and cellular immune response was apparent. Most sheep with focal (tuberculoid) and some with diffuse lesions (borderline tuberculoid), all with scant or no acid-fast bacilli in the intestine, had positive results of the IFN-gamma assay and skin test. Most sheep with diffuse lesions and high numbers of bacilli (borderline lepromatous) were test negative. CLINICAL RELEVANCE: Cellular immune response-based and serologic tests are useful tools for seeking evidence of paratuberculosis. Each technique detects different types of immune-reacting sheep, and their simultaneous use may detect most infected animals.

Animals↗
PubMed1995

Ex vivo induction of TNF-alpha and IL-6 mRNA in bovine whole blood by Mycobacterium paratuberculosis and mycobacterial cell wall components.

Johne's disease is a chronic enteritis of cattle and other ruminant species that is of worldwide economic importance. The cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) have been associated with granuloma formation and wasting in other disease syndromes. The potential role of these cytokines in the development and progression of Johne's disease has not been investigated. Using reverse transcriptase polymerase chain reaction (RT-PCR) and specific bovine oligonucleotide cytokine primers and probes for bovine TNF-alpha and IL-6, we examined the ex vivo expression of mRNA for these inflammatory cytokines in whole blood from healthy cattle. Cytokine mRNA levels increased after a brief incubation of bovine whole blood with Mycobacterium paratuberculosis or its lipoarabinomannan (LAM). Muramyl dipeptide (MDP) and Escherichia coli LPS also stimulated TNF-alpha and IL-6 mRNA expression. Several strains of M. paratuberculosis were tested and found to have similar abilities to stimulate TNF-alpha and IL-6 mRNA expression. Several strains of the closely related Mycobacterium avium, and the unrelated saprophyte, Mycobacterium phlei, had somewhat less ability to stimulate TNF-alpha and IL-6 mRNA expression.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1991

Antibodies to Mycobacterium paratuberculosis in patients with Crohn's disease.

IgG antibodies against Mycobacterium paratuberculosis protoplasmic antigen were looked for by an enzyme immunosorbent assay in patients with Crohn's disease, Ulcerative colitis, active pulmonary tuberculosis, past pulmonary tuberculosis, and in healthy controls. Serum reactivity for these antibodies was not correlated to PPD skin test positivity without history of mycobacterial disease. A cutoff based on the mean absorbance value of a pool of healthy blood donors was chosen. Positive values were found in 12/24 (50%) patients with active pulmonary tuberculosis and 2/10 (20%) skin-test-positive subjects with past pulmonary tuberculosis as expected, because antigenic sharing is common among different mycobacteria. The control group of blood donors showed borderline positivities in 3/149 cases (2.01%). Positive values were found in 4/108 (3.70%) patients with Crohn's disease and 2/40 (5%) with ulcerative colitis. We conclude that our data do not support a causal relationship between the M. paratuberculosis and Crohn's disease, but occasional patients with inflammatory bowel diseases show unexpected positivities for these mycobacterial antibodies.

Adolescent↗
PubMed1999

Characterization of Mycobacterium paratuberculosis p36 antigen and its seroreactivities in Crohn's disease.

Recent data using improved cultural, molecular, and serological techniques have strengthened the association of Mycobacterium paratuberculosis with Crohn's disease, an inflammatory bowel disease (IBD) with unknown etiology. To provide more evidence of an etiological association, antibody reactivities of Crohn's disease patients were tested by immunoblotting against M. paratuberculosis-recombinant antigens. A clone containing a 1,402-bp insert and expressing a 36K-antigen (p36) was analyzed. No homology was found between the deduced amino acid sequence of p36 and any protein sequences compiled in the GenBank indicating that p36 is a novel mycobacterial protein. The reactivity of 199 serum samples was tested against the p36 by immunoblotting technique. Sera from 77 of 89 (86.5%) Crohn's disease patients and 16 of 18 (89%) sera from patients with tuberculosis and leprosy reacted with p36 compared to 5 of 42 (12%) ulcerative colitis and non-IBD control sera (p < 0.0001). In addition, p36 reacted to all sera from 10 normal controls that were Bacillus Calmette-Guerin (BCG)-immunized and only to 10% of 40 normal controls that were not BCG-immunized. The fact that sera from Crohn's disease patients reacted to p36 with the same high frequency as the sera from patients that were exposed to mycobacterial antigens further supports the hypothesis of the mycobacterial etiology in Crohn's disease.

Antibodies, Bacterial↗