HEMATOLOGY AND PLASMA CHEMISTRY OF HOUSE SPARROWS (PASSER-DOMESTICUS) ALONG THE SUMMER MONTHS AND AFTER TESTOSTERONE TREATMENT

Young and adult male house sparrows were captured once reproduction had finished (early summer) and before molting had taken place. They remained in outdoor aviaries until molting was completed (late summer). Half of them received a chronic treatment of testosterone. A blood sample was collected both at the beginning and at the end of the captivity period, Both young and admit birds showed a hemoconcentration from the beginning to the end of the summer, which is suggested to be related to the natural cycle of water shortage, White blood cell number was higher in young than in adults but no change was observed during the study period. Plasma proteins and their nitrogenous wastes decreased over the summer months which raised the hypothesis of plasma proteins as a store for amino acid needs during molting. Testosterone increased erythrocyte number and blood hemoglobin content. It also altered leucocyte number, but in an age dependent manner, It also increased plasma proteins, but only in adult birds. Plasma triglycerides were unaltered by age, month of sampling or testosterone treatment.