Updated project metadata. The objective of this study was to identify and quantify proteomic profiles of head kidney of rainbow trout Oncorhynchus mykiss. Specific pathogen free rainbow trout (mean length 15 ± 1 cm) were maintained in recirculating de-chlorinated water at 19±1 °C. Prior to the experiment, fish were distributed between 9 aquaria, 18 fish per aquarium. The test groups were infected by immersion of Yersinia ruckeri strains: CSF007-82 (biotype 1) and 7959-11 (biotype 2). The control group was immersed similar with sterile broth medium. There were 3 aquaria per each group (CSF007-82-infected, 7959-11-infected and control). Nine fish from infected and control fish groups were anaesthetized with MS-222 at 3, 9 and 28 days post exposure and sampled aseptically. Each head kidney was washed three times with sterile phosphate-buffered saline containing a cocktail of mammalian protease inhibitors. Head kidney samples were snap-frozen in liquid nitrogen and stored at –80 °C.