The PATASEL project (Animal Phenotyping for the Agroecological Transition of Livestock Systems), which is driven by the distributed research infrastructure LIPH4SAS, aims at developing high-throughput phenotyping in the livestock sector with the objective of promoting, by supplying services and technological developments adapted to the implementation of projects related to adaptation to climate change and agroecological transition of livestock. LIPH4SAS allows both functional exploration at different levels (vertical phenotyping) and measurements, at the animal level, on large batches of livestock (horizontal phenotyping) of various genotypes, with controlled health status, located in controlled and characterized environments. The phenotypes, measured directly on the animals via sensors or indirectly via biological samples, include long chronicles enabling dynamic studies of major biological functions, their interactions (trade-offs between functions) and their variation factors. These data will allow the development of modeling for predictive purposes (virtual twins) and to propose genetic improvement strategies and precision livestock farming practices to optimize multi-performance. The high-throughput phenotyping tools currently available within LIPH4SAS are currently too limited to match requirements in terms of horizontal phenotyping. The PATASEL project aims to enable LIPH4SAS to increase its capacity in terms of high-throughput equipment, with a fourfold objective: 1) to contribute, by providing livestock phenotyping facilities, to the 4 "flagships" projects of the PEPR AE&ICT involving animals (WAIT4, HOLOBIONTS, AGRIBIO and COBREEDING); 2) to make LIPH4SAS data and equipment available to future projects related to the agroecological transition of livestock farming; 3) to contribute, through technological watch and development activities, to the elaboration and testing of equipment favouring the agroecological transition; 4) to increase its digital capabilities, particularly in terms of data management and FAIRisation. To achieve these objectives, PATASEL proposes to acquire and install equipment to measure priority traits to address the challenges of agroecological transition and that are necessary to the 4 "flagships" projects mentioned above: measurement of greenhouse gas production in ruminants, of the dynamics of body weight and ingestion of concentrated feed, fodder and water (which will provide information on feed efficiency, environmental impact, health and behavior), the installation of sensors and cameras, which will enable studies on behavior, emotions and cognition. They will be completed by a reinforcement of the logistics of collection/supply of biological samples for phenotyping in platform/laboratory (molecule dosage, multi-omics, microbiota...), by enhanced immunophenotyping capacities, the acquisition of an infrared thermography device, which enables the indirect measurement of various characteristics (food quality, methane production, health...), equipment allowing precise measurements of environmental conditions (temperature, precipitation, etc.), the reinforcement of the logistics of collection/supply of biological samples for more advanced phenotyping (assay of molecules, multi-omics, etc. ) or to provide biological material for other projects (microbiotes...). These acquisitions will be accompanied by a watch and targeted technological developments, as well as an important effort on the management (quality, safety, etc.) and FAIRisation of data, training and dissemination. The PATASEL project will be conducted in close interaction with the other livestock projects of the PEPR AE&ICT.