Bacterial Pneumonia in Captive Wild Boars in Southern Brazil - Etiological and Pathological Causes


  • Natalha Biondo
  • Karine Ludwig Takeuti
  • Julia Helena Montes
  • Laura Lopes de Almeida
  • Caroline Pinto de Andrade
  • Priscila Zlotowski
  • David Driemeier
  • David Emilio Santos Neves de Barcellos



Background: Respiratory diseases are one of the major health issues described in intensive pig production, causing important economic losses. However, there is little information on the prevalence, etiology and clinical-pathological presentation of these diseases in wild boars. For this reason, this work investigated the presence in captive wild boars of pneumonic lesions and bacterial pathogens commonly detected and associated with respiratory diseases in domestic pigs.

Materials, Methods & Results: A total of 226 captive wild boar lungs from two farms were examined in a slaughterhouse in Southern Brazil. The pneumonic lesions were classified as cranioventral, dorsocaudal, and disseminated, and the quantification of lesions was calculated. From the total of 226 lungs, 121 were collected for laboratory examination. Lungs with macroscopic lesions suggestive of pneumonia were collected for histological, bacteriological and molecular analysis. The molecular analysis was performed to detect the presence of Actinobacillus (A.) pleuropneumoniae, Glaesserella (G.) parasuis, Mycoplasma (M.) hyopneumoniae, Mycoplasma (M.) hyorhinis and Streptococcus (S.) suis serotype 2. The percentages of histological lesions and bacterial agents and their association were calculated. Cranioventral consolidation (75.2%) was the most prevalent macroscopic lung lesion, followed by disseminated (21.5%) and dorsocaudal (3.3%) distribution. Microscopically, chronic lesions were the most prevalent, representing 70.2% of the lungs. Moreover, BALT hyperplasia was present in 86.5% of the lungs, suppurative bronchopneumonia in 65.7%, and alveoli infiltrate in 46.8%. Six bacterial pathogens commonly described as agents of pig pneumonia were identified by bacterial or molecular methods: Pasteurella (P.) multocida, S. suis, M. hyopneumoniae, A. pleuropneumoniae, G. parasuis and M. hyorhinis. Twenty-eight different combinations of pathogens were identified in 84 samples (69.4%). The most common combinations were: M. hyopneumoniae and A. pleuropneumoniae (13.1%), M. hyopneumoniae, G. parasuis and M. hyorhinis (10.7%), and M. hyopneumoniae, A. pleuropneumoniae and G. parasuis (8.3%). Additionally, M. hyopneumoniae was the most frequent pathogen detected in this study, representing 58.7% of the samples. The detection of M. hyopneumoniae and M. hyorhinis by PCR was associated with the presence of BALT hyperplasia (P < 0.05) and there was also an association between the detection of M. hyopneumoniae by PCR and suppurative bronchopneumonia (P < 0.05). In addition, a significant association (P < 0.05) between the detection of M. hyopneumoniae and A. pleuropneumoniae by PCR and the histological classification (acute, subacute or chronic lesions) was observed.

Discussion: The results of this study were similar to those observed in slaughtered domestic pigs, although, the detection of opportunist pathogens was less frequent than that usually described in pig pneumonia. The high prevalence of pneumonia in captive wild boars at slaughter and the similar characteristics of pneumonia in captive wild boars and domestic pigs suggest that the close phylogenetic relationship between pigs and wild boars could influence the susceptibility of both species to the colonization of the same pathogens, indicating that captive wild boars raised in confined conditions could be predisposed to respiratory diseases, similar to domestic pigs.


Keywords: Mycoplasma hyopneumoniae, lung consolidation, slaughter, Sus scrofa, swine.


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Aragon V., Cerdà-Cuéllar M., Fraile L., Mombarg M., Nofrarías M., Olvera A., Sibila M., Solanes D. & Segalés J. 2010. Correlation between clinico-pathological outcome and typing of Haemophilus parasuis field strains. Veterinary Microbiology. 142(3-4): 387-393. DOI: 10.1016/j.vetmic.2009.10.025.

Asai T., Okada M., Ono M., Irisawa T., Mori Y., Yokomizo Y. & Sato S. 1993. Increased levels of tumor necrosis factor and interleukin 1 in bronchoalveolar lavage fluids from pigs infected with Mycoplasma hyopneumoniae. Veterinary Immunology and Immunopathology. 38(3-4): 253-260. DOI: 10.1016/0165-2427(93)90085-i.

Baraldi T.G., Cruz N.R.N., Pereira D.A., Galdeano J.V.B., Gatto I.R.H., Silva A.F.D., Panzardi A., Linhares D.C.L., Mathias L.A. & Oliveira L.G. 2019. Antibodies against Actinobacillus pleuropneumoniae, Mycoplasma hyopneumoniae and influenza virus and their relationships with risk factors, clinical signs and lung lesions in pig farms with one-site production systems in Brazil. Preventive Veterinary Medicine. 17: 104748. DOI: 10.1016/j.prevetmed.2019.104748.

Baroch J.A., Gagno C.A., Lacouture S. & Gottschalk M. 2015. Exposure of feral swine (Sus scrofa) in the United States to selected pathogens. Canadian Journal of Veterinary Research. 79(1): 74-78.

Biondo N., Schaefer R., Gava D., Cantão M.E., Silveira S., Mores M.A.Z., Ciacci-Zanella J.R. & Barcellos D.E.S.N. 2014. Genomic analysis of influenza A virus from captive wild boars in Brazil reveals a human-like H1N2 influenza virus. Veterinary Microbiology. 168(1): 34-40. DOI: 10.1016/j.vetmic.2013.10.010.

Calderón Díaz J.A., Fitzgerald R.M., Shalloo L., Costa M.R., Niemi J., Leonard F.C., Kyriazakis I. & Manzanilla E.G. 2020. Financial Analysis of Herd Status and Vaccination Practices for Porcine Reproductive and Respiratory Syndrome Virus, Swine Influenza Virus, and Mycoplasma hyopneumoniae in Farrow-to-Finish Pig Farms Using a Bio-Economic Simulation Model. Frontiers in Veterinary Science. 7(November): 1-14. DOI: 10.3389/fvets.2020.556674.

Caswell J.L. & Williams K.J. 2016. Respiratory system. In: Jubb K.P. (Ed). Jubb, Kennedy & Palmer's Pathology of Domestic Animals. 6th edn. St. Louis: Elsevier, pp.526-527.

Ciprián A., Pijoan C., Cruz T., Camacho J., Tórtora J., Colmenares G., López-Revilla R. & De la Garza M. 1988. Mycoplasma hyopneumoniae increases the susceptibility of pigs to experimental Pasteurella multocida pneumonia. Canadian Journal of Veterinary Research. 52(4): 434-438.

Conti E.R., Takeuti K.L., Schwertz C.I., Bianchi R.M., Driemeier D. & Barcellos D.E.S.N. 2021. Agents of pneumonia in slaughtered pigs in southern Brazil. Pesquisa Veterinária Brasileira. 41:e06669 . DOI: 10.1590/1678-5150-PVB-6669.

Costa M.M., Klein C.S., Balestrin R., Schrank A., Piffer I.A., Silva S.C. & Schrank I.S. 2004. Evaluation of PCR based on gene apxIVA associated with 16S rDNA sequencing for the identification of Actinobacillus pleuropneumoniae and related species. Current Microbiology. 48(3): 189-195. DOI: 10.1007/s00284-003-4162-x.

Ecco R., Lazzari A.M. & Guedes R.M.C. 2009. Pneumonia enzoótica em javalis (Sus scrofa). Pesquisa Veterinária Brasileira. 29(6): 461-468.

Fablet C., Marois C., Dorenlor V., Eono F., Eveno E., Jolly J.P., Le Devendec L., Kobisch M., Madec F. & Rose N. 2012. Bacterial pathogens associated with lung lesions in slaughter pigs from 125 herds. Research in Veterinary Science. 93(2): 627-630. DOI: 10.1016/j.rvsc.2011.11.002

Hälli O., Ala-Kurikka E., Wallgren P. & Heinonen M. 2014. Actinobacillus pleuropneumoniae seroprevalence in farmed wild boars in finland. Journal of Zoo and Wildlife Medicine. 45(4): 813-818. DOI: 10.1638/2014-0046.1.

Hansen M.S., Pors S.E., Jensen H.E., Bille-Hansen V., Bisgaard M., Flachs E.M. & Nielsen O.L. 2010. An investigation of the pathology and pathogens associated with porcine respiratory disease complex in Denmark. Journal of Comparative Pathology. 143(2-3): 120-131. DOI: 10.1016/j.jcpa.2010.01.012.

Jirawattanapong P., Stockhofe-Zurwieden N., van Leengoed L., Wisselink H., Raymakers R., Cruijsen T., van der Peet-Schwering C., Nielen M. & van Nes A. 2010. Pleuritis in slaughter pigs: Relations between lung lesions and bacteriology in 10 herds with high pleuritis. Research in Veterinary Science. 88(1): 11-15. DOI: 10.1016/j.rvsc.2009.06.007.

Lin J.H., Chen S.P., Yeh K.S. & Weng C.N. 2006. Mycoplasma hyorhinis in Taiwan: Diagnosis and isolation of swine pneumonia pathogen. Veterinary Microbiology. 115(1-3): 111-116. DOI: 10.1016/j.vetmic.2006.02.004.

Linhares M.B., Belloy L., Origgi F.C., Lechner I., Segner H. & Ryser-Degiorgis M.P. 2015. Investigating the role of free-ranging wild boar (Sus scrofa) in the re-emergence of enzootic pneumonia in domestic pig herds: A pathological, prevalence and risk-factor study. PLoS ONE. 10(3): 1-26. DOI: 10.1371/journal.pone.0119060.

López A. 2006. Respiratory System In: McGavin M.D & J.F. Zachary J.F. (Eds). Pathologic Basis Veterinary Diseases. 4th edn. Ames: Mosby Elsevier, pp.463-558.

Lyoo K.S., Kim J.K., Jung K., Kang B.K. & Song D. 2014. Comparative pathology of pigs infected with Korean H1N1, H1N2, or H3N2 swine influenza A viruses. Virology Journal. 11(1): 1-6. DOI: 10.1186/1743-422X-11-170.

Maciel A.L.G., Loiko M.R., Bueno T.S., Moreira J.G., Coppola M., Dalla Costa E.R., Schmid K.B., Rodrigues R.O., Cibulski S.P., Bertagnolli A.C. & Mayer F.Q. 2018. Tuberculosis in Southern Brazilian wild boars (Sus scrofa): First epidemiological findings. Transboundary and Emerging Diseases. 65(2): 518-526. DOI: 10.1111/tbed.12734.

Markey B., Leonard F., Archambault M., Cullinane A. & Maguire D. 2013. Clinical Veterinary Microbiology. 2nd edn. Dublin: Mosby Elsevier, 920p.

Marois C., Bougeard S., Gottschalk M. & Kobisch M. 2004. Multiplex PCR assay for detection of Streptococcus suis species and serotypes 2 and 1/2 in tonsils of live and dead pigs. Journal of Clinical Microbiology. 42(7): 3169-3175. DOI: 10.1128/JCM.42.7.3169-3175.2004.

Messier S. & Ross R.F. 1991. Interactions of Mycoplasma hyopneumoniae membranes with porcine lymphocytes. American Journal of Veterinary Research. 52(9): 1497-1502.

Meyns T., Dewulf J., de Kruif A., Calus D., Haesebrouck F. & Maes D. 2006. Comparison of transmission of Mycoplasma hyopneumoniae in vaccinated and non-vaccinated populations. Vaccine. 24(49-50): 7081-7086. DOI: 10.1016/j.vaccine.2006.07.004.

Morés M.A.Z., Oliveira Filho J.X., Rebelatto R., Klein C.S., Barcellos D.E.N., Coldebella A. & Morés N. 2015. Aspectos patológicos e microbiológicos das doenças respiratórias em suínos de terminação no Brasil. Pesquisa Veterinária Brasileira. 35(8): 725-733. DOI: 10.1590/S0100-736X2015000800004.

Morrison R.B., Pijoan C., Hilley H.D. & Rapp V. 1985. Microorganisms associated with pneumonia in slaughter weight swine. Canadian Journal of Comparative Medicine. 49(2): 129-137.

Nathues H., Alarcon P., Rushton J., Jolie R., Fiebig K., Jimenez M., Geurts V. & Nathues C. 2017. Cost of porcine reproductive and respiratory syndrome virus at individual farm level – An economic disease model. Preventive Veterinary Medicine. 142: 16-29. DOI: 10.1016/j.prevetmed.2017.04.006.

Oliveira S., Galina L. & Pijoan C. 2001. Development of a PCR test to diagnose Haemophilus parasuis infections. Journal of Veterinary Diagnostic Investigation. 13(6): 495-501. DOI: 10.1177/104063870101300607.

Olvera A., Cerdà-Cuéllar M., Mentaberre G., Casas-Diaz E., Lavin S., Marco I. & Aragon. 2007. First isolation of Haemophilus parasuis and other NAD-dependent Pasteurellaceae of swine from European wild boars. Veterinary Microbiology. 125(1-2): 182-186. DOI: 10.1016/j.vetmic.2007.05.003.

Pacce V.D., Oliveira N.R., Jorge S. & Dellagostin O.A. 2019. Occurrence of Mycoplasma hyopneumoniae in slaughter pigs from southern Brazil. Brazilian Journal of Veterinary Research and Animal Science. 56(1): 1-5. DOI: 10.11606/issn.1678-4456.bjvras.2019.150072.

Pereda A., Cappuccio J., Quiroga M.A., Baumeister E., Insarralde L., Ibar M., Sanguinetti R., Cannilla M.L., Franzese D., Escobar Cabrera O.E., Craig M.I., Rimondi A., Machuca M., Debenedetti R.T., Zenobi C., Barral L., Balzano R., Capalbo S., Risso A. & Perfumo C.J. 2010. Pandemic (H1N1) 2009 outbreak on pig farm, Argentina. Emerging Infectious Diseases. 16(2): 304-307. DOI: 10.3201/eid1602.091230.

Pieters M. & Maes D. 2019. Mycoplasmosis. In: Zimmerman J.J., Karriker L.A., Ramirez A., Schawartz K.J., Stevenson G.W. & Zhang J. (Eds). Diseases of Swine. 11th edn. Hoboken: Wiley-Blackwell, pp.863-883.

Piffer I. & Brito J. 1991. Avaliação e quantificação de lesões em pulmões de supinos.pdf, In: Concórdia: Empresa Brasileira de Pesquisa Agropecuária - EMBRAPA, p.12.

Prophet E.B., Mills B., Arrington J.B. & Sobin L.H. 1992. Laboratory Methods in Histotechnology. Washington: American Registry of Pathology, 279p.

Reiner G., Fresen C., Bronnert S., Haack I. & Willems H. 2010. Prevalence of Actinobacillus pleuropneumoniae Infection in Hunted Wild Boars (Sus scrofa) in Germany. Journal of Wildlife Diseases. 46(2): 551-555. DOI: 10.7589/0090-3558-46.2.551.

Rovira A., Clavijo M.J. & Oliveira S. 2010. Infecção por Mycoplasma hyorhinis em suínos. Acta Scientiae Veterinariae. 38(1): 9-15.

Sánchez del Rey V., Fernández-Garayzábal J.F., Domínguez L., Gottschalk M. & Vela A.I. 2016. Screening of virulence-associated genes as a molecular typing method for characterization of Streptococcus suis isolates recovered from wild boars and pigs. Veterinary Journal. 209: 108-112. DOI: 10.1016/j.tvjl.2015.11.007.

Sánchez del Rey V., Fernández-Garayzábal J.F., Mentaberre G., Briones V., Lavín S., Domínguez L., Gottschalk M. & Vela A.I. 2014. Characterisation of Streptococcus suis isolates from wild boars (Sus scrofa). Veterinary Journal. 200(3): 464-467. DOI: 10.1016/j.tvjl.2014.03.013.

SAS. SAS/STAT User’s Guide. 2005.

Severo D.R.T., Werlang R.A., Mori A.P., Baldi K.R.A., Mendes R.E., Surian S.R.S., Coldebella A., Kramer B., Trevisol I.M., Gomes T.M.A. & Silva V.S. 2021. Health profile of free‐range wild boar (Sus scrofa) subpopulations hunted in Santa Catarina State, Brazil. Transboundary and Emerging Diseases. 68(2): 857-869. DOI: 10.1111/tbed.13752.

Sibila M., Mentaberre G., Boadella M., Huerta E., Casas-Díaz E., Vicente J., Gortázar C., Marco I., Lavín S. & J. Segalés. 2010. Serological, pathological and polymerase chain reaction studies on Mycoplasma hyopneumoniae infection in the wild boar. Veterinary Microbiology. 144(1-2): 214-218. DOI: 10.1016/j.vetmic.2009.12.019.

Sibila M., Nofrarías M., López-Soria S., Segalés J., Valero O., Espinal A.& Calsamiglia M. 2007. Chronological study of Mycoplasma hyopneumoniae infection, seroconversion and associated lung lesions in vaccinated and non-vaccinated pigs. Veterinary Microbiology. 122(1-2): 97-107. DOI: 10.1016/j.vetmic.2007.01.010.

Souza T.C.G.D., Silva V.S., Mores M.A.Z., Kramer B., Leme R.A., Silva Porto G. & Alfieri A.A. 2021. Mycoplasma hyopneumoniae in free-living wild boars in Paraná, Brazil. Brazilian Journal of Microbiology. DOI: 10.1007/s42770-021-00516-0.

Sreta D., Kedkovid R., Tuamsang S., Kitikoon P. & Thanawongnuwech R. 2009. Pathogenesis of swine influenza virus (Thai isolates) in weanling pigs: An experimental trial. Virology Journal. 6: 1-11. DOI: 10.1186/1743-422X-6-34.

Stakenborg T., Vicca J., Butaye P., Imberechts H., Peeters J., De Kruif A., Haesebrouck F. & Maes D. 2006. A multiplex PCR to identify porcine mycoplasmas present in broth cultures. Veterinary Research Communications. 30(3): 239-247. DOI: 10.1007/s11259-006-3226-3.

Takeuti K.L., Watanabe T.T.N., Castro L.A., Driemeier D. & Barcellos D.E.S.N. 2013. Histopathological and immunohistochemical characterization of pneumonia caused by co-infection between Pasteurella multocida and Mycoplasma hyopneumoniae in swine. 41(1117): 1-6.

Takeuti K.L., Barcellos D.E.S.N., Andrade C.P., Almeida L.L. & Pieters M. 2017. Infection dynamics and genetic variability of Mycoplasma hyopneumoniae in self-replacement gilts. Veterinary Microbiology. 208: 18-24. DOI: 10.1016/j.vetmic.2017.07.007.

Vicente J., León-Vizcaíno L., Gortázar C., Cubero M.J., González M. & Martín-Atance P. 2002. Antibodies to selected viral and bacterial pathogens in European wild boars from southcentral Spain. Journal of Wildlife Diseases. 38(3): 649-652. DOI: 10.7589/0090-3558-38.3.649.

Zimmerman J.J., Karriker L.A., Ramirez A., Schawartz K.J., Stevenson G.W.& Zhang J. 2019. Diseases of Swine. 11th edn. Hoboken: Wiley-B



How to Cite

Biondo, N., Ludwig Takeuti, K., Montes, J. H., Lopes de Almeida, L., Pinto de Andrade, C., Zlotowski, P., Driemeier, D., & Santos Neves de Barcellos, D. E. (2021). Bacterial Pneumonia in Captive Wild Boars in Southern Brazil - Etiological and Pathological Causes. Acta Scientiae Veterinariae, 49.




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