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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.)

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]

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]