Urinary peptidome analyses for the diagnosis of chronic kidney disease in dogs

•Capillary electrophoresis coupled to mass spectrometry analysis demonstrated presence of ˜5400 peptides in canine urine.•Of these peptides, 133 were differentially excreted between dogs with and without chronic kidney disease (CKD).•Two predictive biomarker models of CKD were constructed using differentially excreted peptides.•Both models diagnosed CKD with an area under the receiver operating characteristic curve of 0.88 in an independent cohort.•Most differentially excreted peptides represented fragments of collagen I.