Box-and-whisker plots of urinary (a) and serum (b) klotho concentrations. The boxes represent the 25th and 75thpercentiles, and the central lines in the boxes represent the median values.The whiskers represent the range of concentrations. Dots represent outliers. a The asterisk represents a statistically lower UrKl/Cr in dogs with IRISstages 3 (p = 0.001) compared to control dogs. b Asterisk represents astatistically lower serum klotho concentration in dogs with IRIS stages 2 (p= 0.001) and 3 (p = 0.001) compared to control dogs.