Severe outbreak of pasteurellosis in sows: a case description
- Riferimento: G. Marruchella et al.
- Abstract: Sow mortality represents a relevant issue in the modern pig industry and can negatively impact the profitability of farming. Sow mortality rate should range between 3-6% on a yearly basis, but higher rates are quite commonly reported. Disease conditions of the locomotor, digestive, reproductive and urinary systems are most frequently observed in dead/euthanized sows. On the other hand, respiratory diseases are rare in this category of animals, the most severe episodes resulting from the introduction of a “new” infectious agent into the breeding stock, thus in absence of an adequate level of herd immunity. We describe herein the main clinical, pathological and microbiological findings observed during a severe outbreak of respiratory disease, which occurred in a breeding pig herd in Central Italy. The respiratory syndrome affected a very high percentage of pregnant and lactating sows (around 30%), both primiparous and multiparous. Within two weeks, the mortality rate reached 15%. At necropsy, serous-fibrinous pleuritis, along with large foci of acute bronchopneumonia, affecting the cranioventral parts of both lungs, represented the most relevant pathological findings in animals under study. In depth bacteriological investigations identified a capsular type D and hgbB-positive Pasteurella multocida strain as the sole causative agent. Pneumonic pasteurellosis usually affects grower/finishing pigs and represents the final stage of the so-called porcine respiratory disease complex. As a matter of fact, Pasteurella multocida rarely acts as the primary cause of porcine pneumonia, rather being considered an opportunist which complicates primary infections caused by other bacteria and/or viruses. The co-factors which likely contributed to determine such a severe respiratory syndrome in sows are largely unknown. Speculatively, we hypothesize that resulted from the introduction of a “new” strain of P. multocida, which infected immunologically naïve sows. The poor level of biosecurity adopted, as well as the kinetics of this outbreak, argue in favour of such a scenario.
- Note: //
- Specie: animali da reddito
- Anno: 2019
- Rivista: Large Animals Review
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