higher lipolysis compared to low SCS herdmates [34]. In other species, CXCR1 is expressed by adipocytes [35], and its ligand, IL8, inhibits adipogenesis through down- regulation of the transcription factor peroxisome prolif- erator-activated receptor-g (PPAR-g) gene [36]. IL8 and CXCR1 may indirectly influence fatty acid synthesis in the mammary gland through this PPAR-g regulation