The purpose of this study was to obtain preliminary information on intraindividual variations of biochemical parameters in racing pigeons (Columba livia). Blood was sampled from the basilic vein at 3- to 4-day intervals on 15 occasions in 8 male and 8 female 1- to 3-year-old, healthy racing pigeons. Six clinical chemistry parameters were investigated, including aspartate aminotransferase (AST). creatine kinase (CK), glucose (GLU), lactate dehydrogenase (LDH), total protein (TP). and uric acid. For each parameter. mean, median, standard deviation, minimum, maximum, and coefficient of variation were evaluated for the whole group, as well as for each individual separately. A high degree of individuality. measured by the index of individuality (IoI), for certain clinical chemistry analytes was demonstrated even within a small, well-defined group. Only TP (IoI = 0.5) met the criteria for a very high degree of individuality. which is defined as IoI less than or equal to 0.6. All other analytes had an IoI between 0.7 (AST and CK) and 0.9 (GLU and LDH). indicating a high to medium degree of individuality. Reference values based on the individual patient may help to improve diagnostic interpretation of clinical chemistry values through a better understanding of biological variation in the healthy individual. These data may help overcome the lack of established reference values in rarer species.