L'unité GABI propose un séjour post-doctoral "Studying trade-offs between resilience, health and production using top-down and bottom-up approaches"

Background:

In the framework of the European Partnership on Animal Health and Welfare (EUPAHW, www.eupahw.eu), our research project (2024-2026, 16 partners) has for objective to identify resilience indicators and their relation (trade-offs) with health, welfare and production traits so that we could integrate novel resilience traits in selective breeding.

The issue of trade-offs, for example between health and production traits, is an increasing issue in livestock farming and even more so in an agroecological transition vision. It is a truly complex research question, which requires ambitious, multidisciplinary and across-scales research.

Your mission will be to explore trade-offs between resilience, health and production in chicken and small ruminants using two complimentary approaches: multivariate data analyses and mechanistic modelling, in two phases:

Phase 1: Deciphering the molecular mechanisms of trade-offs between health and efficiency in chicken by analysis of RNAseq transcriptomic data.

In two experimental INRAE chicken lines (selected for a vaccine response and its control line), we showed, from a phenotypic point of view, trade-offs between vaccine response and body weight gain. Blood and muscle samples were taken sequentially after vaccination. The postdoc will be in charge of analysing this comprehensive set of original phenotypic and transcriptomic data on the question of trade-offs between immunocompetence and growth by performing:

Differential expression analysis with R/Bioconductor package edgeR …
Functional enrichment analysis with available online tools and databases (String, Ingenuity Pathway Analysis, ClueGo etc)
Expression clusters of highly correlated genes will be identify using WGCNA
Interpretation of the results: differential expression, functional enrichment, co-expression clusters.
The postdoc will be able to bring new knowledge, contributing to the deciphering of the molecular mechanisms underlying trade-offs among life history traits. The results, when combined with other omics information, will pave the way to design sustainable genomic breeding programme taking into account trade-offs between immune and efficiency traits.

Phase 2: Simulation of the trade-offs between resilience and performance in contrasted environments

The broader context of trade-offs, and in particular the trade-off between resilience production traits, will be studied using mechanistic models. Resilience has a cost as it relies on a complex of underlying physiological and behavioural mechanisms.  This can create trade-offs with other resource demanding traits but the expression of these trade-offs is affected by the environment.

We have state-of-the-art models that simulate the lifetime performance of animals according to their capacities to acquire and allocate energy resources.  These mechanistic models allow simulation of the dynamic interplay between resilience and other performance traits in differing environmental scenarios, and thus allow evaluation of the consequences of selecting on resilience in differing environments.  The work envisaged will:

Integrate resilience mechanisms (response/recovery) into the existing mechanistic model, extending it to include individual animal variability in resilience, and its consequences on other life functions.
Using existing date on lifetime performance and resilience, calibrate and evaluate the impact of this resilience on lifetime performance and longevity.
Develop environmental scenarios with differing types of perturbation
Simulate the impact of environmental variability and harshness on lifetime performance
Quantify the trade-offs between resilience and performance from these simulations
The postdoc will thereby contribute significantly to ascribing a biotechnical and economic value for the trait resilience in different environments and farm management scenarios.

Co-supervision by two interdisciplinary research units, UMR GABI (Jouy-en-Josas) and UMR PEGASE (St Gilles), with research stays at UMR PEGASE (St Gilles)
Strong interdisciplinary interactions with the European Partnership on Animal Health and Welfare

Contact : 

• Pinard-van der Laan Marie-Hélène (marie-helene.pinard@inrae.fr)
• Friggens Nicolas (nicolas.friggens@inrae.fr)