Chronic Kidney Disease (CKD) is defined as a progressive decrease in the filtration capacity of the kidneys. This pathology is commonly found in older cats, but congenital kidney abnormalities (i.e. present from birth) may exist in young cats. Frequently reported symptoms are increased water consumption and urine output, progressive weight loss, decreased appetite and tiredness. They are often hidden and appear when the disease is already at an advanced stage (> 40% of the kidneys functions are affected). As the kidney no longer plays its role as a filter, blood waste such as urea is no longer eliminated, cats become dehydrated and hypertension develops. All these elements alter the cat's quality of life and can lead to death.