Pigs and pig organs are frequently used prior to human trials in experimental transplant research into how to optimise human transplantation. But what exactly happens when transplant professionals perform experimental research on pigs? Similarly, what happens when a pig is on the surgical table? Based on ethnographic fieldwork in Danish transplant research laboratories, we investigate how pig experiments facilitate ‘collaborative intimacies’ among medical professionals. Collaborative intimacies are used here as an empirical and theoretical framework for conceptualising and re-imagining the social relationships between species and the medical disciplines that emerge in laboratory work. Collaborative intimacies in the lab provide medical training and facilitate moral reflection and social networking among transplant professionals. As such, we argue that research utilising animal models is not only about technological progress and ethical dilemmas; rather, collaborative intimacies make us understand how intimate relations among medical professionals in translational research unfold and how such relations matter for professional and technological futures.