Fig. 4. Cutaneous water evaporation (CWE), skin temperature T_s and body temperature T_b in anesthetized pigeons, 0, 20 and 50min after propranolol (filled circles) and clonidine (open circles) administration. Both drugs induced intense CWE, concomitant with a decrease in T_s and T_b in the heat-acclimated HAc (solid lines; N=7), but not in the non-acclimated NAc (broken lines; N=8) pigeons. Mild hypothermia was also observed in the clonidine-treated pigeons. Values are means ± S.E.M. Asterisks denote values significantly different from control values (at time 0) ^*P<0.05, ^**P<0.005.