ABSTRACT: Declining metabolic function with aging is a conserved phenotype across many species. While aging-associated changes in metabolic status have been investigated rigorously in humans, less is known about metabolic aging in dogs. In this cross-sectional study, we aimed to examine changes in metabolic health with age, and any associations with frailty and quality of life, in a diverse population of companion dogs. This cross-sectional study enrolled 451 mature, adult companion dogs. Serum adiponectin, ALP, ALT, AST, cholesterol, insulin, IGF-1 and glucose levels were quantified. Additionally, plasma FFA, SFA, PA, OA and LA were quantified in a 61 dog subpopulation. All analytes were significantly associated with age, with the exception of AST. Elevated ALP, ALT, cholesterol, insulin, FFA, PA a
