Fig. 1

a urinary NMR metabolic profiles from feline subjects S1-S4 collected at 60 MHz operating frequency; b 2-dimensional COSY spectrum of signal confirmation for S3 sample showing creatinine cross-peaks; c assigned regions of S3 urinary profile with the following assignments: [1] 3-Hydroxybutyrate/Lactate-CH3/Felinine-CH3 [2] Tentative Felinine Derivative-CH3 [3] Tentative Felinine-CH2 [4] Acetate-CH3 [5] N-Acetyl [6] Pyruvate-CH3 [7] Citrate-CH2AB [8] Citrate-CH2AB [9] Creatinine/Creatine-N-CH2 [10] Felinine-CH2 [11] TMAO-N-CH3/Taurine-CH2/Betaine-CH3 [12] Taurine-CH2 [13] Glycine-CH2 [14] Felinine-CH2 [15] Creatinine-CH2 [16] Tentative Allantoin and Urea-NH2 [17] Aromatic signals consisting of Hippurate-CHs and phenylacetylglycine-CHs