Microbiological assessment of sheep lymph nodes with lymphadenitis found during post - mortem examination of slaughtered

  • PDF / 999,571 Bytes
  • 7 Pages / 595.276 x 790.866 pts Page_size
  • 22 Downloads / 208 Views

DOWNLOAD

REPORT


Acta Veterinaria Scandinavica Open Access

RESEARCH

Microbiological assessment of sheep lymph nodes with lymphadenitis found during post‑mortem examination of slaughtered sheep: implications for veterinary‑sanitary meat control Anna Didkowska1*, Piotr Żmuda2, Ewelina Kwiecień3, Magdalena Rzewuska3, Daniel Klich4, Monika Krajewska‑Wędzina5, Lucjan Witkowski6, Monika Żychska6, Aleksandra Kaczmarkowska1, Blanka Orłowska1 and Krzysztof Anusz1

Abstract  Background:  Microbiological examination of lesions found in slaughtered animals during meat inspection is an important part of public health protection as such lesions may be due to zoonotic agents that can be transmitted by meat. Examination of inflamed lymph nodes also plays a particular important role, as lymphadenitis may reflect a more widespread infection. Such lesions in sheep are mainly caused by pyogenic bacteria but also mycobacteria are occasionally found. Meat inspection data from 2017 to 2018 from southern Poland, especially from the Małopolska region, indicate that purulent or caseous lymphadenitis involving the mediastinal and tracheobronchial lymph nodes (MTLNs) is a common finding. The primary aim of the current study was to determine the aetiology of these lesions. Furthermore, it was investigated how presence of lesions was correlated with age and grazing strategy of affected sheep. Results:  Post-mortem examination revealed purulent or caseous lymphadenitis in the MTLNs of 49 out of 284 animals (17.3%). Subsequent microbiological examination revealed the presence of Corynebacterium pseudotuberculosis (34.7%), Streptococcus dysgalactiae subsp. equisimilis (34.7%), Staphylococcus aureus (8.2%), Enterococcus spp. (2.0%), Trueperella pyogenes (2.0%), and β-haemolytic strains of Escherichia coli (2.0%). Mycobacterium spp. and Rhodococcus equi were not detected. In older sheep, the probability of the presence of purulent or caseous lymphadenitis was higher than in younger, and the risk was increasing by 1.5% with each month of life. Sheep grazing locally had 4.5times greater risk of having purulent or caseous lymphadenitis than individuals summer grazing in the mountains. Conclusion:  The most common aetiological agents of purulent or caseous lymphadenitis in the MTLNs of sheep in the Małopolska region were C. pseudotuberculosis and S. dysgalactiae subsp. equisimilis. Particular attention during post-mortem examination should be paid to the carcasses of older sheep and sheep grazing on permanent pastures, as they seem more prone to develop purulent or caseous lymphadenitis. *Correspondence: [email protected] 1 Department of Food Hygiene and Public Health Protection, Institute of Veterinary Medicine, Warsaw University of Life Sciences “SGGW”, Nowoursynowska 159, 02‑776 Warsaw, Poland Full list of author information is available at the end of the article © The Author(s) 2020. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or