The identification of animals with more efficiency in feed utilization is one of the alternatives to overcome the challenges as increased production costs, increased consumer awareness regarding food safety, animal welfare and environmental impacts of the agriculture and livestock. As feeding expenses account for the main cost of livestock activity, differences among animals in converting diet to beef and milk are of great relevance. Animals that use feed more efficiently need to consume less to reach the same level of production, and thus are more profitable and produce more food per unit area. In addition, increased feeding efficiency provides less nutrient waste and excretion, with positive environmental implications. Thus, the project aims to determine the influence of genetic, production, metabolic and behavioral characteristics on feed efficiency in dairy cattle and the corresponding economic impacts. Experiments are in progress to determine the feeding efficiency of female Gir cattle in the breeding, rearing, transitional and lactation phases, allowing the generation of a consistent database from the same animal population. In the feeding efficiency tests, parameters related to metabolism (partitioning of ingested nutrients and bioenergetic efficiency), reproduction and behavior are measured, and subsequently the associations of these characteristics with feeding efficiency in the different evaluated categories will be studied. Behavioral parameters are measured through the use of precision technologies, such as electronic troughs and drinking fountains to evaluate the dynamics of consumption and feeding behavior, rumination sensors and activity sensors. The techniques of facial mask-based respirometry and thermography are used in search of indirect measurement tools that have a high association with feeding efficiency. Transcriptional profile analysis in hepatic and adipose tissue will also be performed, allowing the identification of specific metabolic pathways differentially expressed in animals with divergent phenotypes for feeding efficiency, as well as the evaluation of the relationship between the ruminal microbial community profile and feeding efficiency. These evaluations will allow reaching conceptual and methodological advances in the evaluation of feeding efficiency for dairy cattle and the identification of tools for indirect and less laborious measurement of this characteristic, in order to enable the expansion of the generation of phenotypes qualified for feeding efficiency. The structuring of the conceptual model for capturing, storing and analyzing experimental data will allow the development of feeding efficiency metrics in dairy cattle. The results of this project will contribute to increasing the productivity and economics of milk production systems in Brazil, consolidating the country as a leader not only in food production but also in the generation of sustainable technologies for animal production in the tropics.