Recently, Jergens et al. highlighted the potential role for dogs with diabetes mellitus as a naturally occurring model of Type 2 diabetes mellitus due to observed alterations in the canine gut microbiota and BA pools seen in this disease and implicated the role of BA signaling mediated by TGR5 and/or FXR [113].This suggestion is strengthened by the known pancreatic expression of TGR5 in dogs [99]. This evidence concerns the gene GPBAR1 and type 2 diabetes mellitus.