To investigate the social dimensions of livestock farming using animal domestic biodiversity, we analyzed the social interactions surrounding farms, to identify the role of local breeds and the dimensions of the farming systems at play. We relied on case studies of two farms raising rare breeds in contrasted territories. We (i) identified the people concerned by the farm and its productions and (ii) characterized their interactions and their links with several dimensions of the livestock farming system. We discuss the role of domestic animal biodiversity as one dimension of livestock farming systems related to others.