Abstract Cell-mediated immune (CMI) responses are typically tested by injecting the skin and monitoring the skin reaction. In chickens, various integumental tissues are suitable to measure the CMI reaction, including the wattle, wing web, toe web and foot pad. Using the Smyth line chicken vitiligo model to study the spontaneous autoimmune destruction of pigment cells in feathers, we have found that one growing feather-tip (3 mm diameter by 8 mm length) yields generous amounts of material for down-stream gene-expression-, histological-, and cell population-analyses. Moreover, growing feathers are easily accessible for microinjection, removal of a feather is minimally invasive, and feathers are very suitable for repeated sampling during an immune response. To investigate the potential of the feather as a window into tissue immune responses, time-course studies were conducted comparing leukocyte infiltration in wattles, wing webs and growing feathers in response to injection of vehicle, PHA or LPS, and during the recall response to Mycobacterium butyricum. Based on histology and immunohistochemical staining, leukocyte infiltration profiles over a 72 hour period were similar in all three tissues tested. Hence, the feather provides excellent opportunity to monitor and assess CMI responses and immunomodulation strategies in situ and via down-stream analyses. Support: Arkansas Experiment Station Animal Health Grant