Detection Of Bovine Tuberculosis Research Articles

First detection of bovine tuberculosis by Ziehl-Neelsen staining and polymerase chain reaction at dairy farms in the Lekok Sub-District, Pasuruan Regency, and Surabaya region, Indonesia.

Bovine tuberculosis (TB) is a zoonotic disease of great public health importance, particularly in Indonesia, where control measures are limited or are not implemented. This study aimed to detect the presence of Mycobacterium pathogens in milk samples from dairy cattle in Pasuruan regency and Surabaya City, East Java, using Ziehl-Neelsen acid-fast staining and polymerase chain reaction (PCR). Milk samples were aseptically collected from 50 cattle in the Lekok Subdistrict, Pasuruan Regency, and 44 from dairy farms in the Lakarsantri Subdistrict, Wonocolo Subdistrict, Mulyorejo Subdistrict, and Kenjeran Subdistrict, Surabaya, East Java. To detect Mycobacteria at the species level, each sample was assessed by Ziehl-Neelsen staining and PCR using the RD1 and RD4 genes. The results of PCR assay from 50 samples in Lekok Subdistrict, Pasuruan Regency showed that 30 samples (60%) were positive for Mycobacterium tuberculosis and two samples (4%) were positive for Mycobacterium bovis, although Ziehl-Neelsen staining did not show the presence of Mycobacterium spp. In the Surabaya region, 31 samples (70.45%) were positive for M. tuberculosis and three samples (6.8%) were positive for M. bovis. Six samples (13.63%) from all PCR-positive samples could be detected microscopically with Ziehl-Neelsen. The presence of bovine TB in this study supports the importance of using a molecular tool alongside routine surveillance for a better understanding of the epidemiology of bovine TB in East Java.

Comparative analysis of tuberculin and defined antigen skin tests for detection of bovine tuberculosis in buffaloes (Bubalus bubalis) in Haryana state, India.

Bovine tuberculosis (bTB) is a chronic disease that results from infection with any member of the Mycobacterium tuberculosis complex. Infected animals are typically diagnosed with tuberculin-based intradermal skin tests according to World Organization of Animal Health which are presently in use. However, tuberculin is not suitable for use in BCG-vaccinated animals due to a high rate of false-positive reactions. Peptide-based defined skin test (DST) antigens have been identified using antigens (ESAT-6, CFP-10 and Rv3615c) which are absent from BCG, but their performance in buffaloes remains unknown. To assess the comparative performance of DST with the tuberculin-based single intradermal test (SIT) and the single intradermal comparative cervical test (SICCT), we screened 543 female buffaloes from 49 organized dairy farms in two districts of Haryana state in India. We found that 37 (7%), 4 (1%) and 18 (3%) buffaloes were reactors with the SIT, SICCT and DST tests, respectively. Of the 37 SIT reactors, four were positive with SICCT and 12 were positive with the DST. The results show that none of the animals tested positive with all three tests, and 6 DST positive animals were SIT negative. Together, a total of 43 animals were reactors with SIT, DST, or both, and the two assays showed moderate agreement (Cohen's Kappa 0.41; 95% Confidence Interval (CI): 0.23, 0.59). In contrast, only slight agreement (Cohen's Kappa 0.18; 95% CI: 0.02, 0.34) was observed between SIT and SICCT. Using a Bayesian latent class model, we estimated test specificities of 96.5% (95% CI, 92-99%), 99.7% (95% CI: 98-100%) and 99.0% (95% CI: 97-100%) for SIT, SICCT and DST, respectively, but considerably lower sensitivities of 58% (95% CI: 35-87%), 9% (95% CI: 3-21%), and 34% (95% CI: 18-55%) albeit with broad and overlapping credible intervals. Taken together, our investigation suggests that DST has a test specificity comparable with SICCT, and sensitivity intermediate between SIT and SICCT for the identification of buffaloes suspected of tuberculosis. Our study highlights an urgent need for future well-powered trials with detailed necropsy, with immunological and microbiological profiling of reactor and non-reactor animals to better define the underlying factors for the large observed discrepancies in assay performance, particularly between SIT and SICCT.

The impact of changing the cut-off threshold of the interferon-gamma (IFN-γ) assay for diagnosing bovine tuberculosis in Ireland

In Ireland, the interferon-gamma (IFN-γ) assay is routinely used as an ancillary test interpreted in parallel with the single intradermal comparative tuberculin test (SICTT) to maximize the detection of bovine tuberculosis (bTB) infected animals. Up until 2018, a positive test result was recorded in the IFN-γ ELISA assay following whole blood stimulation with purified protein derivative (PPD)-bovine (B), PPD-avian (A) and nil sample (N), using the interpretation criteria, B-N > 50 optical density units (OD), B > 100 and B-A > 0. Following a review of available data, the threshold of the B-A component changed to B-A > 80. As predicting the impact of changing the cut-off thresholds for the IFN-γ test de novo is challenging, the aims of this study were to follow animals that initially tested negative using the new IFN-γ assay interpretation criteria and investigate their future risk of disclosure with bTB, with a focus on animals that otherwise would have been removed when using the older interpretation criteria (0 < B-A ≤ 80). Enrolled animals (n = 28,669 cattle from 527 herds) were followed up for two years (2019–2021), or to point of bTB detection or death. At the end of follow-up, 1151 (4.0%) of enrolled animals were bTB cases. The majority of these cases were diagnosed using SICTT (80.5%). The cumulative number of positive animals that would have been removed if the old cut-off (0 < B-A ≤ 80) was used amounted to 1680 cattle (5.9% of the enrolled cohort). Of these, 127 (7.5%) were diagnosed with bTB during follow-up. In contrast, 1024 of the 1151 cattle which subsequently tested positive during the study period following a negative IFN-γ test would not have been identified with the old or new IFN-γ cut-off criteria. Survival analysis showed that animals that would have been removed under the old interpretation criteria were at increased risk of a positive diagnosis with bTB during follow-up compared to other test negative animals. A newly developed risk prediction model (using a Cox proportional hazard model) showed that age, animal number of SICTT tests, number of inconclusive SICTT tests, B-A (IFN-γ assay), B-N (IFN-γ assay), animals from store herds and the percentage of the rest of the herd that were positive during the breakdown were statistically significantly associated with bTB detection. However, inclusion of the IFN-γ OD variables did not show added value in terms of prediction performance of the model.

LAP-MALDI MS Profiling and Identification of Potential Biomarkers for the Detection of Bovine Tuberculosis.

Detecting bovine tuberculosis (bTB) primarily relies on the tuberculin skin test, requiring two separate animal handling events with a period of incubation time (normally 3 days) between them. Here, we present the use of liquid atmospheric pressure (LAP)-MALDI for the identification of bTB infection, employing a three-class prediction model that was obtained by supervised linear discriminant analysis (LDA) and tested with bovine mastitis samples as disease-positive controls. Noninvasive collection of nasal swabs was used to collect samples, which were subsequently subjected to a short (<4 h) sample preparation method. Cross-validation of the three-class LDA model from the processed nasal swabs provided a sensitivity of 75.0% and specificity of 90.1%, with an overall classification accuracy of 85.7%. These values are comparable to those for the skin test, showing that LAP-MALDI MS has the potential to provide an alternative single-visit diagnostic platform that can detect bTB within the same day of sampling.

Serological detection of bovine tuberculosis and John’s disease by Elisa in South Gujarat

Serological detection of bovine tuberculosis and John’s disease by Elisa in South Gujarat

Advantages of Real-time PCR and RD4-PCR as Molecular Methods for Rapid Detection of Bovine Tuberculosis in Bulgaria

Representatives of Mycobacterium tuberculosis complex (MTBC) are potential causative agents of tuberculosis in animals and humans, and Mycobacterium bovis is considered a major one among domestic and wild ruminants. In the last twenty years, the role of another representative of MTBC – Mycobacterium caprae, has been proven in the countries of Central and Southern Europe. Study sample included 121 diagnostic materials from lymph nodes and lungs from cattle, positively and doubtfully PPD tuberculin-reacted, originating from 6 farms belonging to the 4 regions in Northern and Southern Bulgaria. The bacteriological examination showed typical growth for mycobacteria for 110 (90.9%) samples, which was confirmed by qPCR. By RD4-PCR we proved that 102 (92.7%) of the mycobacterial strains were M. caprae and the remaining 8 strains (7.3%) were M. bovis. This defines M. caprae as a dominant species in the etiology of tuberculosis in cattle in Bulgaria.&#x0D; In conclusion, we confirmed that the application of real-time PCR is an accurate and convenient method for rapid detection of M. bovis from cattle in the Bulgarian settings. RD4-PCR provides a sufficiently high differentiation and can be used for first-line typing of M. bovis isolates in Bulgaria. This proves the need for the simultaneous application of both methods in the diagnosis of bovine tuberculosis in Bulgaria.

Differential detection of IgM and IgG antibodies to chimeric antigens in bovine tuberculosis

Recent studies have suggested the potential of innovative serologic tests for accurate and rapid detection of bovine tuberculosis (bTB). Dual Path Platform (DPP) technology has been used to develop rapid animal-side antibody tests for Mycobacterium bovis infection in a range of livestock and wildlife host species. The present study evaluated diagnostic performance of DPP BovidTB IgM/IgG assay designed for differential detection of bovine IgM and IgG antibodies against two chimeric antigens, DID38 and TBf2, respectively, using 662 well-characterized serum samples from M. bovis-infected and bTB-free cattle collected in the United States, Great Britain, France, and South Africa. Test sensitivity and specificity ranged from 71% to 100% and from 95% to 100%, respectively, depending on the country, with overall accuracy of 83%. No significant risk of cross-reactivity with serum samples from cattle infected with most relevant species of mycobacteria other than M. bovis was found. The DPP BovidTB IgM/IgG assay may be suitable for use in multi-test algorithms to improve current strategies for bTB surveillance.

Application of Multivariate Mapping in Classification of Diseases of Bunaji Cattle Slaughtered at Jos Abattoir, Plateau State, Nigeria

The study aimed at describing objectively, the interdependence among diseases of cattle slaughtered in Jos abattoir and mapping using multivariate techniques. In the study, slaughter health records of cattle slaughtered in Jos abattoir, Plateau State for ten years (2006-2016) was reviewed. The cases at ante-mortem and postmortem were based on examination of animals, organs and carcasses by Veterinary officers. We performed principal component and factor analysis using R 3.0.3 statistical software. Factor 1 was sensitive to lumpy skin disease, wound, mastitis, tuberculosis (TB), Contagious Bovine Pleuropneumonia (CBPP) and jaundice while factor 2 had high scores for abscess, helminthosis and TB. The appearance of TB in both factors implies that TB was a major public health threat among the cattle slaughtered in Jos abattoir from the year 2006 – 2011. From 2012-2016, however, mastitis, splenomegaly, hardware disease and TB were diseases and conditions observed to be more prevalent in Jos abattoir slaughter records. Bovine tuberculosis has been mapped to be the most prevalent disease with significant animal-human interface on the Plateau. Testing using molecular tools and development of algorithm tracker for the detection of bovine tuberculosis should be of great significance to public health in attempt to mitigate the wave of transmission of zoonotic diseases between animals and humans.

Genome-wide association studies for the identification of cattle susceptible and resilient to paratuberculosis.

Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease or paratuberculosis (PTB), with important animal health and economic implications. There are no therapeutic strategies to control this disease, and vaccination with inactivated vaccines is limited in many countries because it can interfere with the intradermal test used for bovine tuberculosis detection. Thus, infected animals either get culled after a positive ELISA or fecal PCR result or die due to clinical disease. In this study, we review recent studies aimed to discover genetic markers which could help to identify and select cattle less susceptible and more resilient to PTB. In recent years, the genotyping and subsequent imputation to whole-genome sequence (WGS) has allowed the identification of single-nucleotide polymorphisms (SNPs), quantitative trait loci (QTL), and candidate genes in the Bos taurus genome associated with susceptibility to MAP infection. In most of these genome-wide association studies (GWAS), phenotypes were based on ante-mortem test results including serum ELISA, milk ELISA, and detection of MAP by fecal PCR and bacteriological culture. Cattle infected with MAP display lesions with distinct severity but the associations between host genetics and PTB-associated pathology had not been explored until very recently. On the contrary, the understanding of the mechanisms and genetic loci influencing pathogen resistance, and disease tolerance in asymptomatic individuals is currently very limited. The identification of long-time asymptomatic cattle that is able to resist the infection and/or tolerate the disease without having their health and milk production compromised is important for disease control and breeding purposes.

Development and evaluation of a Mycobacterium bovis interferon-γ enzyme-linked immunospot (ELISpot) assay for detection of bovine tuberculosis

Bovine tuberculosis (bTB) caused by Mycobacterium bovis is an important zoonotic disease. This infection is difficult to control because of the limited ability of the tuberculin skin test (TST) and ancillary IFN-γ release assay to detect all infected animals. In this study, we aimed to develop an efficient assay based on the enzyme-linked immunospot (ELISpot) technique for the diagnosis of bTB, with IFN-γ monoclonal antibodies 3E9 and Bio-labeled 6F8 used as capture and detection antibodies, respectively. As expected, there were significantly more M. bovis-specific spot-forming units (SFU) in bTB-infected cattle than in healthy cattle when an M. bovis-specific antigen, CFP-10-ESAT-6 fusion protein (CE protein), was used. The M. bovis IFN-γ ELISpot assay demonstrated a high level of agreement (90.83%) with the BOVIGAM ELISA test (Thermo Fisher Scientific) for detecting bTB. Furthermore, 3 of 109 cattle tested negative by both the TST and the BOVIGAM ELISA tests, but positive by the ELISpot assay (TST- ELISA- ELISpot+). During subsequent long-term monitoring, these 3 cattle became TST+ ELISA+ ELISpot+. These results suggest that the M. bovis IFN-γ ELISpot assay we established could detect infected cattle earlier than the BOVIGAM ELISA test.

Potential for improved detection of bovine tuberculosis by targeting combined blood biomarkers in multi-test algorithms

Bovine tuberculosis (bTB) control programs can be improved by combined use of tests for humoral and cell-mediated immune responses targeting multiple biomarkers of Mycobacterium bovis. To further the diagnostic benefits of this approach, we used Dual Path Platform (DPP) technology to test sera from cattle with naturally acquired bTB in the United States (US) and Spain for the presence of M. bovis antigen, IgM and/or IgG antibodies to MPB70/MPB83 fusion antigen in conjunction with tuberculin skin tests (TST) or interferon-gamma release assays (IGRA). When TST was complemented with detection of IgM and IgG antibodies, the diagnostic sensitivity increased from 85.4% to 95.1% in the US and from 64.2% to 81.5% in Spain. Likewise, adding the DPP assays enhanced IGRA diagnostic sensitivity from 82.7% to 93.8% in Spain. Detection of circulating M. bovis antigen showed added value when used in combination with the DPP antibody assays but it was limited when analyzed in the context of TST or IGRA results. Present findings support the benefits of a multi-test approach for the ante-mortem diagnosis of bTB in cattle.

Tuberculin test errors and its effect on detection of bovine tuberculosis

Bovine tuberculosis is an endemic disease in Egypt, a notable gap exists between limited cases identified by single intradermal tuberculin test performed through the national control program and higher detected cases at abattoirs. Therefore, this study aimed to investigate epidemiological situation and causes of the previously mentioned gap in Middle-Delta Region. A total of 25 emergency-slaughtered animals of unknown tuberculosis-status were investigated by cocktail-antigens ELISA and post-mortem examination. Five visible tuberculous-lesion cases were detected and confirmed by PCR, ELISA was sensitive and predictive of the existence of tuberculous-lesions; 4(80%) out of 5 visible-lesion cases were seropositive. True prevalence among the slaughtered animals was 27%. In addition, tuberculin-testing of 400 animals during the national control program was evaluated, many technical and procedural errors were detected, and all animals were negative.Out of them, 55 animals were tested by ELISA before the application of tuberculin test, 30 (54.5%) animals were seropositive. To confirm the effect of the reported errors on reliability of tuberculin test, reference serum of 20 tuberculosis-positive animals that were tested by standard-procedures tuberculin test and their status were confirmed by PCR after slaughtering, were tested by ELISA. A complete matching was evident, the 20 standard-tuberculin positive animals were all seropositive. In conclusion, bovine tuberculosis is endemic at high levels in the study area, reported errors of tuberculin test during national control program may be the cause for missing tuberculosis cases and not tuberculin test itself and finally, a further wide-scale funded study is required to discover the situation throughout Egypt.

Detection of bovine tuberculosis in cattle and buffaloes in three districts of Punjab by immunological and molecular techniques

Detection of bovine tuberculosis in cattle and buffaloes in three districts of Punjab by immunological and molecular techniques

Using of Gamma Interferon γ-IFN and Multiplex PCR (m-PCR) for Detection of Bovine Tuberculosis in Dairy Herds in Egypt

Many diagnostic tools are essential for Mycobacterium bovis (M. bovis) eradication program. This study aimed to apply γ-IFN assay to detect bovine tuberculosis and multiplex PCR (m-PCR) for rapid identification of Mycobacterial isolates. A total no. of 150 cattle in 10 small farms at different Governorates in Egypt, were previously gave suspected results with comparative cervical tuberculin test (SICCT), they retested after 60 days later again with SICCT and bovine gamma-interferon (γ-IFN) immunoassay. Eighty-seven (58%) out of total 150 animals were +ve reactors by SICCT test while 80 (53.3%) animals gave +ve γ-IFN assay. The isolated M. bovis by conventional culturing and identification tests were +ve 55 (63.2%) out 87. The γ-IFN assay sensitivity and specificity gave 82.9% and 93.8% respectively. For rapid identification of different mycobacterial isolates using m-PCR two set of primers were used. The first set gave 123bp DNA PCR product expressing IS6110 insertion element for Mycobacterium tuberculosis (MTBC). The other one gave 500bp from RvD1Rv2031c genomic sequence definite to M. bovis. M-PCR findings were in a concordance with results of conventional culturing and identification tests with high sensitivity and specificity (100%). From this study, it is concluded that diagnosis of bovine tuberculosis (BTB) used tuberculin test and γ-IFN assay with m-PCR for rapid identification M. bovis isolates in living herds.

Study on supplemental test to improve the detection of bovine tuberculosis in individual animals and herds

BackgroundBovine tuberculosis (bTB), is a worldwide disease caused by Mycobacterium bovis (M. bovis). The success of bTB eradication and control programs is based on early detection and the removal of reactors from a herd thus routine testing and cull strategy have been applied globally. Since the late nineteenth century, the Tuberculin Skin Test (TST) has been the primary antemortem test available to support bTB eradication campaigns. Due to the TST limitations in terms of Se and Sp, the credibility of the diagnosis is frequently questioned given the occurrence of false-positive and false-negative reactions, therefore, it is necessary to confirm reactive animals using other methods, ensuring the reliability of the diagnosis. The aim of this study was to evaluate the sensitivity and specificity of a multiplex enzyme-linked immunosorbent assay (ELISA) relative to the tuberculin test used for the diagnosis of tuberculosis in cattle in Brazil.ResultsLack of agreement between comparative cervical tuberculin test and ELISA IDEXX TM was observed. The 2 animals positive on the comparative cervical tuberculin test did not react at the ELISA IDEXX TM and 22 negative reactors by comparative cervical tuberculin test were positive by the ELISA IDEXX TM. The ELISA IDEXX TM showed sensitivity that is significantly lower than the official screening test the single cervical tuberculin. ELISA IDEXX TM also detected infected animals and herds undetected by the comparative cervical tuberculin test. The parallel use of comparative cervical tuberculin test and ELISA IDEXX TM increased sensitivity and the feasibility bTB screening.ConclusionsThe results obtained here suggest that the ELISA IDEXX TM may be a supplemental test for the detection of Mycobacterium bovis infection in regions without routine testing and slaughter, where the disease generally progresses to more advanced stages and antibody responses are likely to be more prevalent. Evidence to support the validation of the ELISA IDEXX™ as a supplemental test for bTB eradication programs was provided.

Evaluation of the performance of slaughterhouse surveillance for bovine tuberculosis detection in Castilla y Leon, Spain

Post-mortem inspection (PMI) of routinely slaughtered cattle in abattoirs is an extremely valuable tool for detecting bovine tuberculosis (bTB) infected herds that can supplement active surveillance activities. However, its true performance is difficult to assess due to the multiple factors that may affect it. Here, we determined relative efficiencies in the detection of bTB-compatible lesions and probabilities of subsequent laboratory confirmation of abattoirs located in Castilla y Leon, one of the regions with the largest cattle population in Spain, between 2010 and 2017. The slaughtered animal population was split based on the results of the ante-mortem tests (reactors or non-reactors), and two generalized linear multivariable mixed models were fitted to each subpopulation to calculate the risk of lesion detection and laboratory confirmation per abattoir while accounting for the effect of potential confounding variables.Throughout the 8-year period, ∼30,000 reactors and >2.8 million non-reactor animals in the ante-mortem tests were culled in the abattoirs under study. Bovine TB compatible lesions were detected in 4,710 (16%) reactors and 828 (0.03%) non-reactor animals, of which >95% were confirmed as infected through bacteriology. The probability of disclosure of bTB-like lesions was associated with the animal subpopulation, type of source unit, the herd size, the year of slaughter, the breed and age of the animal, and/or the season of slaughter. The probabilities of detection of bTB-like lesions varied largely depending on the abattoir in both subpopulations, ranging from 603 to 3,070 per 10,000 animals for the reactors and 0.2–16.1 per 10,000 animals for the non-reactor animals.Results obtained here will help to quantify the performance of PMI in abattoirs in Castilla y Leon and the between-abattoir variability, and to identify animals at increased risk of having bTB-like lesions detected during PMI based on animal- and farm-related factors.

Development of a lateral flow immunochromatography test for the rapid detection of bovine tuberculosis

Detection of specific antibodies would be a useful test strategy for bovine tuberculosis (bTB) as a complement to the single skin test. We developed a lateral flow immunochromatography (LFIC) test for rapid bTB detection based on the use of a conjugate of gold nanoparticles with a recombinant G protein. After evaluating 3 Mycobacterium bovis (MB) antigens: ESAT-6, CFP-10 and MPB83 for the control line, we selected MPB83 given it was the most specific. The performance of the test was analyzed with 820 bovine sera, 40 sera corresponding to healthy animals, 5 sera from animals infected with Mycobacterium avium subsp. paratuberculosis (MAP) and 775 sera of animals from herds with bTB. All these sera were also submitted to a validated bTB-ELISA using whole-cell antigen from MB. From the 775 sera of animals from herds with bTB, 87 sera were positive by the bTB-ELISA, 45 were positive by LFIC and only 5 animals were positives by skin test (TST). To confirm bTB infection in the group of TST (−), bTB-ELISA (+) and LFIC (+) animals, we performed postmortem examination in 15 randomly selected animals. Macroscopically, these 15 animals had numerous small and large yellow-white granulomas, characteristic of bTB, and the infection was subsequently confirmed by PCR in these tissues with lesions (gold standard).No false positive test result was detected with the developed LFIC either with the sera from healthy animals or from animals infected with MAP demonstrating that it can be a useful technique for the rapid identification of animals infected with bTB.

Biopsy and Tracheobronchial Aspirates as Additional Tools for the Diagnosis of Bovine Tuberculosis in Living European Bison (Bison bonasus).

Simple SummaryIn this study, additional methods of collecting material for bovine tuberculosis diagnosis in living European bison were introduced. We showed a potential usage of tracheobronchial aspirates and ultrasound-guided biopsies from lateral retropharyngeal lymph nodes in living animals for diagnostics. We confirmed that the isolation of Mycobacterium caprae in living European bison is possible, as is the respiratory shedding of viable M. caprae in this host. This study is important as tuberculosis is a real threat for European bison which is an endangered species and the improvement of diagnostics can help with better health monitoring and further restitution. The diagnosis of bovine tuberculosis (BTB) in living wildlife remains a complex problem, and one of particular importance in endangered species like European bison (Bison bonasus). To identify infection and avoid the unnecessary culling of such valuable individuals, current best practice requires the collection and culture of material from living animals, as mycobacteria isolation remains the gold standard in BTB diagnosis. However, such isolation is challenging due to the need for the immobilization and collection of appropriate clinical material, and because of the sporadic shedding of mycobacteria. In the present study, we evaluated the potential of sampling for the detection of BTB in a group of seven living European bison suspected of being infected with Mycobacterium caprae. The specimens were collected both as swabs from the nasal and pharyngeal cavities, tracheobronchial aspirates (TBA), ultrasound-guided biopsies from lateral retropharyngeal lymph nodes, and post mortem, from mandibular, retropharyngeal and mediastinal lymph nodes. Clinical samples were tested for mycobacterial species via mycobacteriological culture and PCR. M. caprae was isolated from collected material in two out of four living infected individuals (TBA, biopsy) and mycobacterial DNA was detected in three out of four (TBA, pharyngeal swab) bison. This is the first report of isolation of M. caprae in living European bison. Our findings demonstrate the value of diagnostic tests based on both molecular testing and culture in European bison and confirm the respiratory shedding of viable M. caprae in this host species.

Interactive web-based tool for evaluating the spread of bovine tuberculosis and brucellosis in Colombia

Background: Bovine tuberculosis (BTB) and brucellosis are associated with devastating losses in the livestock sector in Colombia and even in developed countries. Real-time disease surveillance is a key strategy to control and eradicate infectious disease outbreaks. Objective: To design an epidemiological tool for monitoring BTB and brucellosis in Colombia. Methods: An interactive platform for disease mapping of BTB and brucellosis during an observation period between years 2004 and 2019 was designed. Results: Our analysis showed that the provinces of Cundinamarca and Valle del Cauca are regions affected by BTB and brucellosis epidemics, respectively (p&lt;0.001). Furthermore, increased case detection of BTB was reported in 2012 and brucellosis in 2019 (p&lt;0.001). Conclusions: This epidemiological platform allows tracking BTB and tuberculosis hotspots, identifying trends over time, and provides useful information to animal health authorities for designing new strategies in control programs.

Development of a flow cytometry assay for bovine interleukin-2 and its preliminary application in bovine tuberculosis detection

Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), poses a risk of infection for livestock, humans, and wildlife. An interferon (IFN)-γ release assay has been used with tuberculin skin tests to detect bTB; however, infected animals may still be missed. Previous studies have suggested that bovine interleukin-2 (BoIL-2) may act as a potential biological marker for the diagnosis of bovine infectious diseases. However, a detailed evaluation of IL-2 as a diagnostic target for bTB is lacking. Therefore, we established hybridoma cell lines that produced monoclonal antibodies (mAbs) recognizing the native BoIL-2 and developed a flow cytometry assay, based on the BoIL-2 mAbs, for detecting M. bovis-specific IL-2. Subsequently, the method was utilized for a preliminary investigation of bTB in cattle; significantly (P < 0.0001) more CD4+IL-2+ T cells were detected in infected cattle than in healthy animals when a specific mycobacterial antigen CFP-10–ESAT-6 fusion protein was used. Moreover, our method demonstrated high coincidence rates with the BOVIGAM® test and an IFN-γ flow cytometry assay for the diagnosis of bTB. These findings show that the present method may be useful for detecting bTB.