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The Eurasian wild boar ( Sus scrofa ) is a key wildlife host for tuberculosis (TB) in central and southwestern Spain, posing a challenge to TB eradication in livestock. New strategies, including the use of beneficial microbes, are being explored to mitigate wildlife diseases. This study evaluated the effect of oral supplementation with postbiotic antimycobacterial metabolites produced using Ingulados' lactic acid bacteria (LAB) collection on TB development in wild boar. A total of 20 game estates in mid-western Spain were divided into two groups: one fed with standard feed containing the postbiotic product and a control group fed without postbiotics. Data were collected from wild boar during hunting events pre- and post-supplementation. The presence of TB-like lesions (TBLLs), lesion severity and seropositivity against Mycobacterium bovis were assessed. Postbiotic supplementation led to a 36.87% reduction in TBLLs and a 35.94% decrease in seropositivity. Notably, young wild boar showed a 64.72% reduction in TBLLs and an 81.80% drop in seropositivity, suggesting reduced transmission. These findings support the potential of postbiotics as a safe, feasible and sustainable tool to control TB in wild boar, offering a promising addition to broader TB eradication efforts.

Background: Wild boar is an important reservoir of Mycobacterium tuberculosis variant bovis , the main causative agent of bovine tuberculosis (bTB). A proportion of tuberculosis (TB)-affected wild boars shed M tuberculosis by nasal route, favouring the maintenance of bTB in a multihost scenario. The aim of this work was to assess if M tuberculosis nasal excretion is influenced by factors commonly associated with high TB prevalence in wild boar., Methods: TB diagnosis and M tuberculosis isolation were carried out in 112 hunted wild boars from mid-western Spain. The association between the presence of M tuberculosis DNA in nasal secretions and explanatory factors was explored using partial least squares regression (PLSR) approaches., Results: DNA from M tuberculosis was detected in 40.8 per cent nasal secretions of the TB-affected animals. Explanatory factors provided a first significant PLSR X's component, explaining 25.70 per cent of the variability observed in M tuberculosis nasal shedding. The presence of M tuberculosis in nasal secretions is more probable in animals suffering from generalised TB and mainly coinfected with Metastrongylus species and porcine circovirus type 2, explaining nearly 90 per cent of the total variance of this model., Conclusion: Measures aiming to control these factors could be useful to reduce M tuberculosis shedding in wild boar., Competing Interests: Competing interests: None declared., (© British Veterinary Association 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Research on management of bovine tuberculosis (bTB) in wildlife reservoir hosts is crucial for the implementation of effective disease control measures and the generation of practical bTB management recommendations. Among the management methods carried out on wild species to reduce bTB prevalence, the control of population density has been frequently used, with hunting pressure a practical strategy to reduce bTB prevalence. However, despite the number of articles about population density control in different bTB wildlife reservoirs, there is little information regarding the application of such measures on the Eurasian wild boar (Sus scrofa), which is considered the main bTB wildlife reservoir within Mediterranean ecosystems. This study shows the effects of a management measure leading to a radical decrease in wild boar population density at a large hunting estate in Central Spain, in order to assess the evolution of bTB prevalence in both the wild boar population and the sympatric fallow deer population. The evolution of bTB prevalence was monitored in populations of the two wild ungulate species over a 5-year study period (2007-2012). The results showed that bTB prevalence decreased in fallow deer, corresponding to an important reduction in the wild boar population. However, this decrease was not homogeneous: in the last season of study there was an increase in bTB-infected male animals. Moreover, bTB prevalence remained high in the remnant wild boar population., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Mycobacterium bovis infections in fallow deer have been reported in different countries and play an important role in the epidemiology of bovine tuberculosis (bTB), together with other deer species. There is little knowledge of the pathogenesis of bTB in fallow deer. The aim of this study was to perform a histopathological characterisation of the granulomas induced by M. bovis in this species and the immunohistochemical distribution of different cell subsets (CD3+, CD79+, macrophages) and chemical mediators (iNOS, TNF-α, IFN-γ) in the different developmental stages of granulomas. Stage I/II granulomas showed a marked presence of macrophages (MAC387+) expressing high iNOS levels while stage III/IV granulomas showed a decrease in the number of these cells forming a rim surrounding the necrotic foci. This was correlated with the presence of IFN-γ expressing cell counts, much higher in stage I/II than in stage III/IV. The number of B cells increased alongside the developmental stage of the granuloma, and interestingly the expression of TNF-α was very low in all the stages. This characterisation of the lesions and the local immune response may be helpful as basic knowledge in the attempts to increase the vaccine efficacy as well as for disease severity evaluation and for the development of improved diagnostic tools. Immunohistochemical methods using several commercial antibodies in fallow deer tissues are described., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Non-tuberculous mycobacteria ( NTM) are widely distributed in the environment, particularly in wet soil, marshland, rivers or streams, but also are causative agents of a wide variety of infections in animals and humans. Little information is available regarding the NTM prevalence in wildlife and their effects or significance in the bovine tuberculosis ( bTB) epidemiology and diagnosis. This research shows the most frequently NTM isolated in lymph nodes of wild boar ( Sus scrofa) from southern Spain, relating the NTM presence with the individual characteristics, the management of animals and the possible misdiagnosis of Mycobacterium bovis in concurrent infections. A total of 219 NTM isolates were obtained from 1249 wild boar mandibular lymph nodes sampled between 2007 and 2011. All but 75 isolates were identified by the PCR-restriction analysis- hsp65, and a partial sequencing of the 16S r DNA was carried out to identify the rest of the isolates. Results showed that Mycobacterium chelonae was the most frequently isolated NTM specie (133 isolates, 60.7%), followed by Mycobacterium avium (24 isolates, 11%). No relation was found regarding sex, body condition and management, but M. chelonae was more frequently detected in adults, whereas M. avium was more prevalent in subadults. The high NTM prevalence observed in the studied wild boar populations could make difficult the b TB diagnostic. [ABSTRACT FROM AUTHOR]

The potential role of wild animals in the maintenance and spread of tuberculosis (TB) infection in domestic livestock is of particular importance in countries where eradication programs have substantially reduced the incidence of bovine tuberculosis but sporadic outbreaks still occur. Mycobacterium bovis is the agent mainly isolated in wildlife in Spain, but recently, infections by Mycobacterium caprae have increased substantially. In this study, we have analysed 43 mandibular lymph nodes samples containing TB-like lesions from 43 hunted wild boar from Madrid and Extremadura (central and south-western regions of Spain). After isolation, identification and typing of Mycobacterium tuberculosis complex isolates, we found that 23 mandibular lymph nodes involved M. caprae infections and 20 M. bovis. The lesions were compared for histopathology (different granuloma stage and number of multinucleated giant cells (MNGCs)), and acid-fast bacilli (AFBs) were quantified in the Ziehl-Neelsen-stained slides. Granulomas produced by M. caprae showed more stage IV granulomas, more MNGCs and higher AFBs counts than those induced by M. bovis. In conclusion, lesions caused by M. caprae would be more prone to the excretion of bacilli, and infected animals result as a high-risk source of infection for other animals. [ABSTRACT FROM AUTHOR]

Background: Deer tuberculosis is a chronic zoonotic infectious disease, despite the existence of socio-economic and zoonotic risk factors, but at present, there has been no systematic review of deer tuberculosis prevalence in mainland China. The aim of this meta-analysis was to estimate the overall prevalence of deer TB in mainland China and to assess possible associations between potential risk factors and the prevalence of deer tuberculosis. Methodology: This study was searched in six databases in Chinese and English, respectively (1981 to December 2023). Four authors independently reviewed the titles and abstracts of all retrieved articles to establish the inclusion exclusion criteria. Using the meta-analysis package estimated the combined effects. Cochran's Q-statistic was used to analyze heterogeneity. Funnel plots (symmetry) and used the Egger's test identifying publication bias. Trim-andfill analysis methods were used for validation and sensitivity analysis. we also performed subgroup and meta-regression analyses. Results: In this study, we obtained 4,400 studies, 20 cross-sectional studies were screened and conducted a systematic review and meta-analysis. Results show: The overall prevalence of tuberculosis in deer in mainland China was 16.1% (95% confidence interval (CI):10.5 24.6; (Deer tuberculosis infected 5,367 out of 22,215 deer in mainland China) 5,367/22215; 1981 to 2023). The prevalence in Central China was the highest 17.5% (95% CI:14.0-21.9; 63/362), and among provinces, the prevalence in Heilongjiang was the highest at 26.5% (95% CI:13.2-53.0; 1557/4291). Elaphurus davidianus was the most commonly infected species, with a prevalence of 35.3% (95% CI:18.5-67.2; 6/17). We also assessed the association between geographic risk factors and the incidence of deer tuberculosis. Conclusion: Deer tuberculosis is still present in some areas of China. Assessing the association between risk factors and the prevalence of deer tuberculosis showed that reasonable and scientific-based breeding methods, a suitable breeding environment, and rapid and accurate detection methods could effectively reduce the prevalence of deer tuberculosis. In addition, in the management and operation of the breeding base, improving the scientific feed nutrition standards and establishing comprehensive standards for disease prevention, immunization, quarantine, treatment, and disinfection according to the breeding varieties and scale, are suggested as ways to reduce the prevalence of deer tuberculosis. [ABSTRACT FROM AUTHOR]

Animal tuberculosis, caused by Mycobacterium bovis, presents a significant threat to both livestock industries and public health. Mycobacterium bovis tests rely on detecting antigen specific immune responses, which can be influenced by exposure to non-tuberculous mycobacteria, test technique, and duration and severity of infection. Despite advancements in direct M. bovis detection, mycobacterial culture remains the primary diagnostic standard. Recent efforts have explored culture-independent PCR-based methods for identifying mycobacterial DNA in respiratory samples. This study aimed to detect M. bovis in nasal swabs from goats (Capra hircus) cohabiting with M. bovis-infected cattle in KwaZulu-Natal, South Africa. Nasal swabs were collected from 137 communal goats exposed to M. bovis-positive cattle and 20 goats from a commercial dairy herd without M. bovis history. Swabs were divided into three aliquots for analysis. The first underwent GeneXpert® MTB/RIF Ultra assay (Ultra) screening. DNA from the second underwent mycobacterial genus-specific PCR and Sanger sequencing, while the third underwent mycobacterial culture followed by PCR and sequencing. Deep sequencing identified M. bovis DNA in selected Ultra-positive swabs, confirmed by region-of-difference (RD) PCR. Despite no other evidence of M. bovis infection, viable M. bovis was cultured from three communal goat swabs, confirmed by PCR and sequencing. Deep sequencing of DNA directly from swabs identified M. bovis in the same culture-positive swabs and eight additional communal goats. No M. bovis was found in commercial dairy goats, but various NTM species were detected. This highlights the risk of M. bovis exposure or infection in goats sharing pastures with infected cattle. Rapid Ultra screening shows promise for selecting goats for further M. bovis testing. These techniques may enhance M. bovis detection in paucibacillary samples and serve as valuable research tools. [ABSTRACT FROM AUTHOR]

This cross-sectional study was conducted at the slaughterhouses/slabs of Oudalan and Ouagadougou in Burkina Faso, between August and September 2013. It aimed at determining the prevalence of bovine tuberculosis (bTB) suggestive lesions in slaughtered cattle carcasses and to identify and characterize the mycobacteria isolated from these lesions. A thorough postmortem examination was conducted on carcasses of a total of 2165 randomly selected cattle. The overall prevalence of bTB suggestive lesions was 2.7% (58/2165; 95% CI 2.1–3.5%). Due to the low number of positive samples, data were descriptively presented. The lesions were either observed localized in one or a few organs or generalized (i.e., miliary bTB) in 96.6% (n = 57) and 3.4% (n = 2), respectively. The identified mycobacteria were M. bovis (44.4%, n = 20), M. fortuitum (8.9%, n = 4), M. elephantis (6.7%, n = 3), M. brumae (4.4%, n = 2), M. avium (2.2%, n = 1), M. asiaticum (2.2%, n = 1), M. terrae (2.2%, n = 1), and unknown non-tuberculous mycobacteria (NTM) (11.1%, n = 5). Moreover, eight mixed cultures with more than one Mycobacterium species growing were also observed, of which three were M. bovis and M. fortuitum and three were M. bovis and M. elephantis. In conclusion, M. bovis is the predominant causative agent of mycobacterial infections in the study area. Our study has identified a base to broaden the epidemiological knowledge on zoonotic transmission of mycobacteria in Burkina Faso by future studies investigating further samples from humans and animals, including wild animals employing molecular techniques. [ABSTRACT FROM AUTHOR]

Mycobacterium bovis (M. bovis) is the causative agent of animal tuberculosis (bTB), infecting and causing disease in several animal species. In areas where there are complex interactions between reservoir hosts and susceptible species, the control of this pathogen is a challenge. The authors report two outbreaks of goat tuberculosis caused by M. bovis in multi-host ecosystems within two protected natural areas of Sicily, where TB is historically endemic. The first outbreak (Farm A) was identified after the incidental detection at the slaughterhouse of TB-like lesions in goat viscera ready to be disposed. Single intradermal cervical tuberculin test (SICT) was performed in Farm A on 205 goats, resulting positive in 10 (4.9%). After slaughtering, six out of ten animals showed TB-like lesions, from which M. bovis spoligotype SB0841 was isolated. The typing did not reveal any epidemiological connection with the neighboring cattle, suggesting that free-ranging type of management exposed the affected goat livestock or wildlife infected with other strains. The second outbreak (Farm B) was detected in a mixed farm (bovine, caprine, and ovine), where relapsing outbreaks of TB in cattle were registered in the previous years after performing the SICT in cohabiting goats. SICT resulted positive in 6/153 (3.9%), and two animals showed bTB-like lesions. No mycobacteria were cultured, and the final diagnosis of TB was achieved by histopathology and immunohistochemistry. The reported outbreaks highlight the importance of assessing the epidemiological, diagnostic, and regulatory critical issue, which is fundamental to optimizing the strategies of eradicating TB in the endemic multi-host ecosystem described. [ABSTRACT FROM AUTHOR]

Animal tuberculosis (TB) in terrestrial mammals is mainly caused by Mycobacterium bovis. This pathogen is adapted to a wide range of host species, representing a threat to livestock, wildlife and human health. Disease heterogeneity is a hallmark of multi‐host TB and a challenge for control. Drivers of animal TB heterogeneity are very diverse and may act at the level of the causative agent, the host species, the interface between mycobacteria and the host, community of hosts, the environment and even policy behind control programmes. In this paper, we examine the drivers that seem to contribute to this phenomenon. We begin by reviewing evidence accumulated to date supporting the consensus that a complex range of genetic, biological and socio‐environmental factors contribute to the establishment and maintenance of animal TB, setting the grounds for heterogeneity. We then highlight the complex interplay between individual, species‐specific and community protective factors with risk/maintenance variables that include animal movements and densities, co‐infection and super‐shedders. We finally consider how current interventions should seek to consider and explore heterogeneity in order to tackle potential limitations for diagnosis and control programmes, simultaneously increasing their efficacy. [ABSTRACT FROM AUTHOR]

Probiotics are noninvasive, environmentally friendly alternatives for reducing infectious diseases in wildlife species. Our aim in the present study was to evaluate the potential of gut commensals such as lactic acid bacteria (LAB) as wildlife probiotics. The LAB selected for our analyses were isolated from European badgers (Meles meles), a wildlife reservoir of bovine tuberculosis, and comprised four different genera: Enterococcus, Weissella, Pediococcus, and Lactobacillus. The enterococci displayed a phenotype and genotype that included the production of antibacterial peptides and stimulation of antiviral responses, as well as the presence of virulence and antibiotic resistance genes; Weissella showed antimycobacterial activity owing to their ability to produce lactate and ethanol; and lactobacilli and pediococci modulated proinflammatory phagocytic responses that associate with protection against pathogens, responses that coincide with the presence of immunomodulatory markers in their genomes. Although both lactobacilli and pediococci showed resistance to antibiotics, this was naturally acquired, and almost all isolates demonstrated a phylogenetic relationship with isolates from food and healthy animals. Our results show that LAB display probiotic benefits that depend on the genus, and that lactobacilli and pediococci are probably the most obvious candidates as probiotics against infectious diseases in wildlife because of their food‐grade status and ability to modulate protective innate immune responses. [ABSTRACT FROM AUTHOR]

The Eurasian wild boar (Sus scrofa) is increasingly considered as a relevant actor in the epidemiology of animal tuberculosis (TB). Therefore, monitoring TB in this species is key when establishing comprehensive control schemes for this disease still present in Europe. No data are available on direct and indirect TB diagnostic methods in wild boars in epidemiological contexts where TB is endemic in cattle and detected in wild boars at low prevalence. We aimed to estimate and compare sensitivity and specificity values for bacterial culture, PCR and three commercial ELISAs, i.e. the TB ELISA-VK (using the bPPD antigen), INgezim TB Porcine and IDEXX M. bovis Ab Test (both using the MPB83 and MPB70 antigens), under field conditions in France. We used frequentist methods, with bacteriology as the gold standard, and a Bayesian formulation of the latent class analysis (LCA), without using a gold standard. Submandibular lymph nodes and sera from 495 wild boars hunter-harvested in three endemic areas (Aquitaine region, Côte d’Or region, and Corsica region) were collected between 2014 and 2016. Only eight individuals were positive for M. bovis by bacteriology (1.61%; CI95% 0.70–3.51%). The LCA method provided high specificities (99.2%; CI95% 98.2–99.8% for INgezim TB Porcine and 99.7%; CI95% 98.8–100% for IDEXX M. bovis Ab Test) and sensitivities (78.5%; CI95% 65.1–88.8% for INgezim TB Porcine and 83.9%; CI95% 58.9–97.2% for IDEXX M. bovis Ab Test) for both ELISAs using the MPB83 and MPB70 antigens. Bacterial culture showed limited sensitivity (42.8%; CI95% 19.0–70.6%), estimated as the probability of a positive result in an animal exposed to M. bovis. PCR and ELISA using the bPPD antigens demonstrated high specificities, and sensitivities intermediates between culture and the ELISAs using the MPB83 and MPB70 antigens. These results suggest that ELISA tests using the MPB83 and MPB70 antigens are useful to detect and monitor TB exposure of wild boar populations in field conditions in France. [ABSTRACT FROM AUTHOR]

Canines in wild boar Sus scrofa constitute weapons used in male–male conflict. We analyzed extensive data for the ecological correlates of canine size in several study sites in Extremadura, Spain, to determine their degree of condition‐dependence and their relationship with health status. Boars with relatively large body size had larger canines than small boars. Canine size was larger in estates without livestock, in estates with low population density, and in estates with rich holmoak forest. These findings are consistent with predictions for condition‐dependent secondary sexual characters. Boars with relatively large canines had large spleens for their body size, higher prevalence of Aujeszky's disease and higher prevalence of macroscopic lesions compatible with Bovine Tuberculosis than boars with relatively small canines. Thus, boars with large canines that were likely to be dominant and have differential access to females were in poorer health than boars with small canines. Since the virus responsible for Aujeszky's disease and Mycobacterium bovis are readily transmitted through direct contact during mating, we suggest that there is a sexual conflict over mating. Boars with large canines that are most likely to copulate with sows are also more likely to be a direct cause of transmission of disease to the sows. [ABSTRACT FROM AUTHOR]

Reactive oxygen and nitrogen species (ROS-RNS) are important defence substances involved in the immune response against pathogens. An excessive increase in ROS-RNS, however, can damage the organism causing oxidative stress (OS). The organism is able to neutralise OS by the production of antioxidant enzymes (AE); hence, tissue damage is the result of an imbalance between oxidant and antioxidant status. Though some work has been carried out in humans, there is a lack of information about the oxidant/antioxidant status in the presence of tuberculosis (TB) in wild reservoirs. In the Mediterranean Basin, wild boar (Sus scrofa) is the main reservoir of TB. Wild boar showing severe TB have an increased risk to Mycobacterium spp. shedding, leading to pathogen spreading and persistence. If OS is greater in these individuals, oxidant/antioxidant balance in TB-affected boars could be used as a biomarker of disease severity. The present work had a two-fold objective: i) to study the effects of bovine TB on different OS biomarkers (namely superoxide dismutase (SOD), catalasa (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS)) in wild boar experimentally challenged with Mycobacterium bovis, and ii) to explore the role of body weight, sex, population and season in explaining the observed variability of OS indicators in two populations of free-ranging wild boar where TB is common. For the first objective, a partial least squares regression (PLSR) approach was used whereas, recursive partitioning with regression tree models (RTM) were applied for the second. A negative relationship between antioxidant enzymes and bovine TB (the more severe lesions, the lower the concentration of antioxidant biomarkers) was observed in experimentally infected animals. The final PLSR model retained the GPX, SOD and GR biomarkers and showed that 17.6% of the observed variability of antioxidant capacity was significantly correlated with the PLSR X’s component represented by both disease status and the age of boars. In the samples from free-ranging wild boar, however, the environmental factors were more relevant to the observed variability of the OS biomarkers than the TB itself. For each OS biomarker, each RTM was defined as a maximum by one node due to the population effect. Along the same lines, the ad hoc tree regression on boars from the population with a higher prevalence of severe TB confirmed that disease status was not the main factor explaining the observed variability in OS biomarkers. It was concluded that oxidative damage caused by TB is significant, but can only be detected in the absence of environmental variation in wild boar. [ABSTRACT FROM AUTHOR]

Animal tuberculosis ( TB) control is globally important for public health, economics and conservation. Wildlife species are often part of the M ycobacterium tuberculosis complex ( MTC) maintenance community, complicating TB control attempts., We describe the current knowledge on global TB distribution and the significance of wildlife hosts; identify insufficiently known aspects of host pathology, ecology and epidemiology; present selected time series in wildlife TB; and summarize ongoing research on TB control, providing additional insight on vaccination., Six specific research needs are identified and discussed, namely: 1) complete the world map of wildlife MTC reservoirs and describe the structure of each local MTC host community; 2) identify the origin and behaviour of generalized diseased individuals within populations, and study the role of factors such as co-infections, re-infections and individual condition on TB pathogenesis; 3) quantify indirect MTC transmission within and between species; 4) define and harmonize wildlife disease monitoring protocols, and apply them in a way that allows proper population and prevalence trend comparisons in both space and time; 5) carry out controlled and replicated wildlife TB control experiments using single intervention tools; 6) analyse cost-efficiency and consider knowledge transfer aspects in promising intervention strategies., We believe that addressing these six points would push ahead our capacities for TB control. A remaining question is whether or not interventions on wildlife TB are at all justified. The answer depends on the local circumstances of each TB hotspot, and is likely to evolve during our collective progress towards TB control in livestock and in wildlife. [ABSTRACT FROM AUTHOR]

Abstract: Limited information has been published on the wild boar immune response against bovine tuberculosis (bTB) and the immunopathogenesis of the pathological hallmark (granuloma) in this species. The main objectives of this study were, on the one hand, to characterize the histopathological features (number of acid-fast bacilli (AFB) and multinucleated giant cells (MNGCs) and the immunohistochemical distribution of different cell subsets (CD3+, CD79a+ and MAC387+) and chemical mediators (iNOS and IFN-γ) in the different developmental stages of granulomas produced by the natural infection of Mycobacterium bovis (M. bovis) in wild boar. On the other hand, the study also aimed to analyze the mechanisms underlying the marked differences in the typical lesional patterns observed in M. bovis infections of wild boar (contained, not generalized) and those previously described in fallow deer (poorly contained, generalized). The majority of granulomas analyzed (95.3%) did not show any AFB with the ZN stain and a low number of MNGCs were identified in the different granuloma stages. The immunohistochemical analysis showed that MAC387 was the only immune marker that produced decreasing positivity by granuloma stage, being statistically significantly lower in stages III and IV when compared to stage I and II. Immune markers for lymphocyte cells (CD3 and CD79a) showed a slight rise in the positivity (which was not statistically significant) in the advanced granuloma stages. In keeping with the presence of large numbers of T cells and macrophages, there was a consistently high level of expression of IFN-γ at all stages of granuloma development without a statistical significant decrease in advanced stages. Also related with the higher presence of macrophages in stage I and II, the expression of iNOS was higher in early stages and sustained until stage III, showing a non statistical significant decrease in stage IV. The macrophage and iNOS activity are more intense and sustained along the granuloma development than those described in fallow deer. Immunohistochemical protocols with a panel of markers for wild boar different cells subsets (CD3+, CD79a+ and MAC387+) and chemical mediators (iNOS and IFN-γ), and their use to further investigate the immune response in this species are provided. [Copyright &y& Elsevier]

Background: Infections with Mycobacterium bovis and closely related members of the Mycobacterium tuberculosis complex (MTC) are shared between livestock, wildlife and sporadically human beings. Wildlife reservoirs exist worldwide and can interfere with bovine tuberculosis (TB) eradication efforts. The Eurasian wild boar (Sus scrofa) is a MTC maintenance host in Mediterranean Iberia (Spain and Portugal). However, few systematic studies in wild boar have been carried out in Atlantic regions. We describe the prevalence, distribution, pathology and epidemiology of MTC and other mycobacteria from wild boar in Atlantic Spain. A total of 2,067 wild boar were sampled between 2008 and 2012. Results: The results provide insight into the current status of wild boar as MTC and Mycobacterium avium complex (MAC) hosts in temperate regions of continental Europe. The main findings were a low TB prevalence (2.6%), a low proportion of MTC infected wild boar displaying generalized TB lesions (16.7%), and a higher proportion of MAC infections (4.5%). Molecular typing revealed epidemiological links between wild boar and domestic - cattle, sheep and goat - and other wildlife - Eurasian badger (Meles meles) and red fox (Vulpes vulpes) - hosts. Conclusions: This study shows that the likelihood of MTC excretion by wild boar in Atlantic habitats is much lower than in Mediterranean areas. However, wild boar provide a good indicator of MTC circulation and, given the current re-emergence of animal TB, similar large-scale surveys would be advisable in other Atlantic regions of continental Europe. [ABSTRACT FROM AUTHOR]

Context Bovine tuberculosis is a persistent disease of livestock in many parts of the world, especially where wildlife hosts co-exist with livestock. In south-western Spain, despite the widespread implementation of test-and-cull strategies for cattle, the herd prevalence in areas with high wild boar densities remains stable. The control of M. bovis infection in wild boar is likely to be essential for effective disease control in livestock. Methods We developed an individual-based model to evaluate whether vaccinating wild boar piglets with oral bait would be an effective strategy to reduce the prevalence of M. bovis infection in wild boar populations. Specifically, we quantified the proportion of piglets requiring vaccination and the number of years the vaccination programme would need to continue to eradicate bTB from wild boar within 25 years, comparing 'managed' populations on hunting estates where supplementary food is provided, with 'unmanaged', free-living populations. Successful vaccination was defined as the proportion of piglets that were delivered the vaccine and were effectively protected from infection. Key results Longer-term (25-year) vaccination strategies were more successful than short-term (5-year) strategies at either eradicating M. bovis or reducing it to below 90% of its original prevalence. M. bovis infection could be eradicated under a 25-year vaccination strategy if 80% of piglets were vaccinated in a managed population or 70% of piglets were vaccinated in an unmanaged population. In contrast, 5-year strategies in which 80% of piglets were vaccinated reduced the prevalence of M. bovis only by 27% or 8% in the managed and unmanaged populations, respectively. Conclusions The results of our simulation model, coupled with the promising results of initial vaccine and oral bait-uptake trials in wild boar indicated that vaccination could be an effective strategy to reduce the prevalence of M. bovis infection in wild boar if used in conjunction with other disease-control measures. Implications The vaccination of piglets over a long-term period has the potential to make an important contribution to the eradication of M. bovis infection from wild boar reservoirs in southern Spain. Wild boar is a host of bovine tuberculosis and can prevent the eradication of the disease from livestock in areas where they coexist. We investigated whether vaccination was effective at reducing the proportion of infected wild boar in the population after 25 years. Our results indicated that the long-term vaccination of wild boar piglets could potentially contribute to the eradication of disease from the livestock. Photograph by Catherine Cowie. [ABSTRACT FROM AUTHOR]

In Europe, animal tuberculosis (TB) due to Mycobacterium bovis involves multi-host communities that include cattle and wildlife species, such as wild boar (Sus scrofa), badgers (Meles meles) and red deer (Cervus elaphus). Red fox (Vulpes vulpes) infections have also been recently reported in some TB endemic regions in the Iberian Peninsula and France, with some of the infected animals shedding M. bovis in urine and feces. In order to understand the pathogenesis of M. bovis infection in foxes and the associated risk of transmission, 12 captive foxes (6 females and 6 males) were inoculated orally with 2 × 107 colony-forming units of a French field isolate of M. bovis. Clinical samples (urine, feces and oropharyngeal swabs) were collected every four weeks and tested for molecular diagnosis and bacteriology. Serological responses were measured by IDEXX M. bovis Ab Test and Multi Antigen Print Immunoassay (MAPIA). At a post-mortem examination performed 12 weeks post infection (wpi), tissues were tested for the presence of M. bovis and associated gross and microscopic TB-like lesions. M. bovis was detected by PCR in bladder swabs of 3 animals at 12 wpi. It was also detected pre-mortem at different time points of the experiment in the oropharyngeal mucus of three individuals and in the feces of nine foxes, with two of them confirmed by bacteriology. All 12 foxes had at least 4 PCR positive samples (out of the 23 tested), and all but 1 fox had at least 1 culture positive sample. The culture negative fox was PCR positive in both retropharyngeal and mesenteric lymph nodes, in line with the results of the other animals. Seroconversion was observed in all foxes except one during the experiment, and in nine at the final time point. No gross visible lesions were found in any animal at the post-mortem examination. The histology showed small granulomas within the lymph nodes, tonsils, liver and lungs from eight animals, with the presence of few acid-fast bacilli. These results confirmed that all orally-infected foxes developed mild TB lesions but they were able to shed mycobacteria in about 75% of cases, 1 month post-infection (9 out 12 foxes). These results show that it is possible to induce typical TB infection experimentally in captive foxes, with measurable M. bovis excretion; such an experimental system could be useful for future evaluations of diagnostics and vaccines in this species. [ABSTRACT FROM AUTHOR]

Simple Summary: This study targeted a small epidemiological area of a selected wildlife-livestock-human interface in Selangor to detect important veterinary and public health mycobacteria in free-ranging wild boar (Sus scrofa) and wild macaques (Macaca fascicularis) using a combination of diagnostic methods, tuberculosis-like lesion (TBLL) detection and nucleic acids detection by conventional and molecular analyses. Conventional PCR on wild boar tissues showed that 75% (9/12) of the lymph node samples were positive for Mycobacterium bovis (95% CI: 46.8–91.1). For macaques, 33.3% (10/30) were positive for Mycobacterium avium (95% CI: 19.2–51.2). Wild animals are considered reservoirs, contributing to the transmission of emerging zoonotic diseases such as tuberculosis (TB). A cross-sectional study was conducted by opportunistic sampling from fresh carcasses of free-ranging wild boar (n = 30), and free-ranging wild macaques (n = 42). Stained smears from these tissues were tested for acid-fast bacilli (AFB) with Ziehl–Neelsen staining. Mycobacterial culture was conducted using Lowenstein–Jensen media and Middlebrook 7H11 agar media. Polymerase chain reaction (PCR) was performed through the detection of the 16S rRNA gene, with multiple sets of primers for the detection of Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium complex (MAC). In wild boars, 30% (9/30; 95% Confidence Interval: 16.7–47.9%) of examined samples showed gross tuberculosis-like lesions (TBLLs). Multiple nodular lesions that were necrotic/miliary with cavitation were found in the submandibular lymph nodes, tonsils, lungs, kidney and liver, while single nodular lesions were found in the mediastinal lymph nodes, spleen and mesenteric lymph nodes. Conventional PCR on the submandibular lymphoid tissues of wild boar (nine samples with TBLLs and three non-TBLL samples) showed that 75% (9/12) were positive for Mycobacterium bovis (95% CI: 46.8–91.1), and 91% (CI: 64.6–98.5) were positive for Mycobacterium avium. For macaques, 33.3% (10/30) were positive for M. avium (95% CI: 19.2–51.2) but negative for MTBC. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis causes pulmonary tuberculosis, a deadly infection of which the clinical expression and prognosis are not fully understood at the individual level, apart from genetic susceptibility traits. We investigated whether individual gut microbiota may correlate with pulmonary tuberculosis status. Culturomics investigations of gut microbiota in two pulmonary tuberculosis patients and two controls in Burkina Faso found 60 different bacterial species in patients and 97 in controls, including 45 in common. Further analysis of the results at the individual level indicated seven bacteria, including Enterococcus mundtii and Enterococcus casseliflavus, which were exclusively cultured in controls. Blind quantitative PCR-based exploration of faeces samples in two cohorts in Burkina Faso and in France confirmed a nonsignificant association of E. mundtii and E. casseliflavus with controls. Further in vitro explorations found four E. mundtii and E. casseliflavus strains inhibiting the growth of M. tuberculosis strains representative of four different lineages as well as Mycobacterium africanum, Mycobacterium canettii, and Mycobacterium bovis, in an inoculum-dependent manner. Heat-killed E. mundtii or E. casseliflavus were ineffective. These unprecedented observations of direct interactions between gut E. mundtii and E. casseliflavus with M. tuberculosis complex mycobacteria suggest that gut microbiota may modulate the expression of pulmonary tuberculosis. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) vaccination could be used as a key part of integrated strategies for the disease's control if an effective and safe vaccine under field conditions is obtained. Recent studies in Spain have evaluated the protective efficacy of two oral vaccines against experimental challenge with live intra-bronchial Mycobacterium bovis in captive badgers: the live-attenuated M. bovis BCG vaccine (Danish strain) and a heat-inactivated M. bovis (HIMB) vaccine. With the objective of increasing the knowledge of the cellular development progress of infection and generating further tools to discriminate between mild and severe TB lesions between and within animals, the immunopathology of tuberculous lesions was studied to characterize the local immune response (cell type profile) within lung granulomas from control (non-vaccinated), BCG vaccinated and HIMB-vaccinated experimentally infected badgers with M. bovis. Four immunohistochemical protocols, for the specific detection of macrophages, T lymphocytes, B lymphocytes and plasma cells within TB granulomas in formalin fixed sections of the right middle lung lobe (lobe targeted for the M. bovis delivery), were performed. Immunolabelled sections were scanned and five randomly selected areas were analyzed with digital image analysis software. The results were expressed as the proportion of the positively immunolabelled area within the total area of the selected site. Data was analyzed using the statistical analysis software (SAS). In the three treatment groups, macrophages were the most abundant inflammatory cells within the granulomas, followed by B lymphocytes and plasma cells. T lymphocyes were absent in those granulomas. This would suggest a predominance of a non-specific innate response mediated by phagocytic cells over an adaptative humoral immune response. The proportion of macrophages and plasma cells was higher in BCG and HIMB-vaccinated badgers, respectively, suggesting the establishment of an adaptative humoral response in HIMB-vaccinated badgers. The lower bacterial load at the lung level, as well as the volume of lesions in lungs using magnetic resonance imaging in badgers with the HIMB vaccine in relation with local immune response presented, must be highlighted, since it would be an advantage in favor of its use under field conditions in terms of reducing TB transmission and environmental contamination. [ABSTRACT FROM AUTHOR]

Background: Sheep have been traditionally considered as less susceptible to Mycobacterium bovis (Mbovis) infection than other domestic ruminants such as cattle and goats. However, there is increasing evidence for the role of this species as a domestic Mbovis reservoir, mostly when sheep share grazing fields with infected cattle and goats. Nevertheless, there is a lack of information about the pathogenesis and the immune response of Mbovis infection in sheep. The goals of this study were to characterize the granuloma stages produced by the natural infection of Mbovis in sheep, to compare them with other species and to identify possible differences in the sheep immune response. Samples from bronchial lymph nodes from twelve Mbovis-naturally infected sheep were used. Four immunohistochemical protocols for the specific detection of T-lymphocytes, B-lymphocytes, plasma cells and macrophages were performed to study the local immune reaction within the granulomas. Results: Differences were observed in the predominant cell type present in each type of granuloma, as well as differences and similarities with the development of tuberculous granulomas in other species. Very low numbers of T-lymphocytes were observed in all granuloma types indicating that specific cellular immune response mediated by T-cells might not be of much importance in sheep in the early stages of infection, when macrophages are the predominant cell type within lesions. Plasma cells and mainly B lymphocytes increased considerably as the granuloma developed being attracted to the lesions in a shift towards a Th2 response against the increasing amounts of mycobacteria. Therefore, we have proposed that the granulomas could be defined as initial, developed and terminal. Conclusions: Results showed that the study of the lymphoid tissue granulomata reinforces the view that the three different types of granuloma represent stages of lesion progression and suggest an explanation to the higher resistance of sheep based on a higher effective innate immune response to control tuberculosis infection. [ABSTRACT FROM AUTHOR]