Effect of heat stress in ewes: Search for indicators in milk using mid-infrared spectra to assess animal health and welfare

• Title: Effect of heat stress in ewes: Search for indicators in milk using mid-infrared spectra to assess animal health and welfare
• PhD student: Morgane GENIN
• Affiliated unit: UMR 791, MoSAR
• Co-supervision:
  • Valérie BERTHELOT (AgroParisTech)
  • Morgane COSTES-THIRE (INP, AgroToulouse)
• Doctoral school: Doctoral School of Agriculture, Food, Biology, Environment and Health
• Project duration: 2025-2028

Project summary:

The agroecological transition relies in particular on grazing ruminants, which makes them particularly sensitive to the effects of climate change: the direct effect of the climate, mainly heat stress, on animal welfare and health, and the indirect effect on water and food resources, mainly grass, whose availability and quality fluctuate. In order to adapt to these new constraints, farmers need robust, practical, inexpensive and socially accepted tools to anticipate risks and develop practices that enable them to manage difficult periods as effectively as possible.

In dairy herds, milk is a readily available biological fluid which, for many farms, is subject to regular milk testing. This monitoring is based on mid-infrared (MIR) analysis to measure the main components of milk, which is used to calculate its purchase price. Its use could be developed and systematised as a herd management tool with the aim of improving animal health and welfare, whether preventively or correctively. The aim of this thesis project is to explore this possibility in dairy sheep flocks.

This thesis therefore aims to study the relationships between MIR spectra and indicators of health and welfare in dairy sheep, particularly in the context of summer heat. Various disciplines are involved: nutrition, health, ethology, modelling and genetics, in order to obtain a comprehensive view of the effects of heat stress at the holobiont level on selected parameters related to the MIR spectra of milk.