Animals 1 Article 1 Blood sampling 1 Corticosterone 1 Glucocorticoids 1 H:L-ratio 1 Leukocyte coping capacity 1 Parus major Passeriformes 1 Passerines 1 Songbirds 1 Stress, Physiological 1 animal 1 animal cell 1 animal experiment 1 bleeding 1 blood sampling 1 brachial vein 1 controlled study 1 corticosterone 1 glucocorticoid 1 heterophil lymphocyte ratio 1 leukocyte count 1 leukocyte function 1 nonhuman 1 physiological stress 1 songbird 1 vein puncture 1