Epistemic-Hunger in the Stable: The Genesis of Bone-Sheep as Experimental Animals in Orthopedic Surgery. The text explores the coming-into-being of bone-sheep as experimental animals in the field of orthopedic surgery from the 1960s onwards. Sheep replaced dogs – mainly for emotional reasons – as test subjects for newly developed implants like plates and screws, which were used for fracture care in humans and in pet animals. Utilizing a praxeographic approach in the framework of material semiotics, the history of bone-sheep is examined more closely in order to explore how different sheep ontologies (e.g. bone-sheep and meat-sheep) are intertwined. Ontologies are understood as specific modes of existence: a set of simultaneous multiple realities which are coproduced by animals and humans and which do not align into a single coherent reality. Materiality is not understood as pre-given but rather as an effect of practices of relating, connecting and cutting – thus producing – heterogeneities like bone-sheep. Those practices can be understood as a form of ’ontological politics', which describes the interactions between different ontological realities. By paying specific attention to the phenomenon of hunger and practices of feeding, the text examines the ontological politics of synchronization between the epistemic hunger – the data-collection or scientific hunger of the researchers – and the ontological hunger of the sheep themselves, which can be seen as crucial in the materialization of bone-sheep.