Defense of Maud Rouault's thesis

Members of the jury:

• Reviewers before defense:
  • Antoine ROQUILLY, University professor - Hospital practitioner, University Nantes, Nantes, France
  • Jean-François VALARCHER, Professor, Swedish University of Agricultural Sciences, Uppsala, Sweden
• President:
• Examiners:
  • Catherine BELLOC, Professor, Oniris, Nantes, France
  • Aude REMOT, Research fellow, INRAE, Nouzilly, France
  • Edouard TIMSIT, Director of Global Innovation Livestock Health and Sustainability, CEVA, Libourne, France
  • Antoine ROQUILLY, University professor - Hospital practitioner, University Nantes, Nantes, France
  • Jean-François VALARCHER, Professor, Swedish University of Agricultural Sciences, Uppsala, Sweden
• PhD director:
  • François Meurens, Professor, Faculty of Veterinary Medicine, Montréal, Canada
• PhD co-director:
  • Gilles FOUCRAS, Professor, ENVT, Toulouse, France
• PhD co-supervisor invited:
  • Sébastien ASSIE, Lecturer, Oniris, Nantes, France

Abstract:

Bovine respiratory disease (BRD) remains a major cause of morbidity in feedlot calves and has significant economic and health impacts. This thesis is based on the hypothesis that combining several complementary diagnostic and prognostic methods could enhance the performance of existing or emerging tools. Thoracic ultrasonography was assessed and validated in beef-breed feedlot calves as a relevant diagnostic tool, although it appears less sensitive than in dairy calves, and may offer etiological insights.
In parallel, multiplex analysis of fifteen cytokines and chemokines allowed for a more detailed characterization of the immune response associated with BRD, in connection with the animal’s medical history, and led to the identification of several promising biomarkers. Finally, a litterature review of clinical prediction rules used in human medicine for community-acquired pneumonia (CAP) was conducted to propose an adaptation suited to bovine medicine. This word highlights the value of an integrated multimodal approach to enable more targeted and rational management of BRD

Keywords:

Pneumonia ; Thoracic ultrasonography ; Cytokines ; Diagnosis ; Prognosis ; Clinical prediction rules