This research project aims to identify novel diagnostic and prognostic biomarkers for the early detection of feline chronic kidney disease (CKD). CKD is a frequently encountered disease in veterinary practices, affecting at least 30% of cats over 15 years of age. Current diagnostic tests only detect CKD once there is extensive damage, so it is of significant clinical and commercial importance to diagnose CKD at an earlier stage. This way, appropriate therapeutic measures can be implemented earlier and thereby improve the prognosis. Novel biomarkers are urgently required. This proposal aims to overcome the limitations of current diagnostic tools and their lack of sensitivity in the earliest stages of disease by applying cutting edge metabolomics technologies to carefully defined prospective and longitudinal clinical cohorts. This proposal: (i) leverages the power of targeted and untargeted metabolomics to discover novel renal biomarkers; (ii) validates their diagnostic and prognostic potential and clinical relevance by evaluating their applicability in the presence of hyperthyroidism and other comorbid diseases; and (iii) assesses their use in the prediction of post-treatment azotaemia in hyperthyroid cats. This proposal is expected to discover novel renal biomarkers for future development of a clinically applicable diagnostic test to improve outcomes for cats with CKD, with both clinical and commercial impact.