Sustainability of ruminant production is of concern to society because of its implications for the environment, the economy and food security. Microbiomes associated with the host play a key role in health, welfare and environmental efficiency in ruminant production systems. However, despite the information already available, we lack the insights to precisely link the causes and mechanisms of microbial influence on ruminant phenotypes. This is because the interconnection and communication between the animal and its different microbiomes have never been studied in a deep, integrated way. The goal of the project is to elucidate the role of ruminant-associated microbiomes and their interplay with the host in early life and throughout fundamental life events. HoloRuminant will use a holistic multi-omics approach to characterise the acquisition and evolution of microbiomes from different body sites, their inheritability and their influence on the host’s resistance to disease and environmental efficiency of production. Specifically we will: determine microbiomes’ functions by combining multi-level information for microbes, host and their interaction; define microbiomes’ roles during challenging life periods such as perinatal, weaning, and after exposure to pathogens; and evaluate the effect of ruminant microbiomes on critical phenotypes for sustainable production, health and welfare. This will allow the identification of novel microbial markers for monitoring, predicting and selecting phenotypes of interest. By engaging actors from the livestock value chain, we will evaluate the socio-economic impact and acceptability of the innovations proposed among stakeholders and the public. HoloRuminant will provide highly innovative, standardized methodologies that will radically advance our understanding of the ruminant holobiont. This knowledge and the tools created will allow the use of microbiome-based diagnostics and solutions for improving ruminant sustainability.

On the Eastern Steppe of Central Asia, the period spanning the Late Bronze Age (1200–700 BCE) and the Early Iron Age (700–400 BCE) witnessed major societal changes, characterised by an increase in social differentiation and interconnectivity. The adoption of mounted pastoralism during the Late Bronze Age may have played a major role in this transformation. At that time, the horse had already been domesticated. It was harnessed, ridden, and probably used for traction, making it possible for the population to travel greater distances. The overwhelming presence of the horse in funerary and ritual monuments clearly indicates that this animal was of central importance and may have been an integrative component of ceremonial activities linking regionally distinct groups. MOBISTEPPE aims to provide an unprecedented understanding of the role played by horses in interactions among the pastoral communities of Mongolia in the Late Bronze Age. This aim will be achieved through the multi-isotopic (C, O, Sr) analysis of the teeth of ancient horses to investigate pastoral mobility. Our hypothesis is that isotopic analysis can be used to reconstruct the size of the territory used by local human communities, and to thereby illuminate the social differentiation and multi-scalar connections among them. However, current limitations in knowledge on the incorporation of Sr isotopes into enamel, the geospatial distribution of isotopic signatures in the environment, and the availability of ancient horse material have prevented testing of this hypothesis. To remove these barriers and thus address the impact of domestic animals in the structuration of past human societies, MOBISTEPPE will combine animal feeding experiments, archaeology, movement ecology, social anthropology, and state-of-the-art isotopic and geospatial analyses and modelling. Specifically, we will (1) conduct controlled feeding experiments on sheep to document how fast the C and Sr isotopic composition of the diet is recorded in the animals’ tissues; (2) characterise and map the variability in Sr isotope values and mobility patterns of different nomadic herder families living in Central Mongolia today using GPS collars to infer the isotope record of mobility in the teeth of the modern herd animals; and (3) excavate, study, and isotopically analyse ancient horse remains from a large number of archaeological structures in that same region. Controlled feeding experiments will provide ground-breaking theoretical results that will be widely applicable in archaeology and beyond. Our work, which is set in an archaeologically rich region, will produce the first Sr isoscape in Eurasia that will be permanently stored and made freely available. This rigorous mapping and modelling approach is at the frontier of Sr isotope research and will be of great interest to the wider scientific community. MOBISTEPPE will bridge the social, natural, and geological sciences and produce new data in at least four disciplines (archaeology, biogeochemistry, ecology, and social anthropology), which will be made available to the widest possible audience. Besides traditional activities aimed at the scientific community (publication and presentation of the scientific results, organisation of an international workshop), MOBISTEPPE contains an ambitious dissemination programme, including (1) training and teaching of students and young researchers (recruited by the project and participating in excavations) and (2) transfer of knowledge to the general public (through a public website, documentary film, miniseries, and photo exhibition).

Milk lipolysis is defined as the hydrolysis of triglycerides, the major component of milk fat. Short-chain fatty acids consequently released in milk are responsible for rancid flavor, unacceptable for consumers, in milk and dairy products. In addition, the presence of partial glycerides impairs milk functional properties such as foaming and creaming abilities. Milk lipolysis, routinely measured by accredited inter-professional dairy laboratories therefore represents an important criterion to assess the quality of milk. High lipolysis indexes in milk lead to appreciable loss of market access for dairy farms. Milk spontaneous lipolysis is a complex interplay between farming practices, animal physiology and animal genetics. In addition, milk induced lipolysis may occur during milking or dairy products manufacturing as results of thermal and/or mechanical shocks during milking and cooling. Lipolysis can thus occur throughout the "milk way", from "udder to cheese". The LIPOMEC employs a multi-actor approach to meet a threefold objective: ? To study the lipolytic system constituted by the lipase, its substrate (the milk fat globule) and a balance of activating or inhibiting cofactors in the three dairy species through the characterization of lipase regulatory networks in milk and/or mammary epithelial cells; ? To establish breeding and feeding strategies those ensure optimal and stable milk quality all year round; ? To develop tools and techniques to monitor and reduce lipolysis all along the "milk way". Our approach is definitely integrative, including animal science, milk biochemistry, milk biophysics, proteomics, lipidomics, genetics, transcriptomics, cell biology techniques, data modeling, and statistics. Interactions between genetics, physiology, farming practices and technological factors related to the milking process will be considered. LIPOMEC is the first large-scale integrative project to study the lipolytic system in the milk and mammary gland from ruminant species.