Respiratory and Cardiovascular Responses in the Hyperthermic Domestic Cock ,

Abstract

ALTHOUGH panting in birds has been studied for a long time from a stand-point of transpiration of water in hyperthermia (Soum, 1896; Kayser, 1930), Saalfeld (1936) was the first to examine systematically hyperthermic polypnea in the pigeon. He described an area of the anterior hypothalmus as containing a “panting center” and an area of the medulla oblongata which contained a respiratory center. Randall and Hiestand (1939) found that reflex panting does not exist in birds although reflex interruption of panting was possible. Although panting dogs are hyperventilated (Richet, 1898) and can demonstrate a 50–60 percent reduction in arterial carbon dioxide concentrations (Anrep and Hammouda, 1932), Saalfeld (1936) postulated that, despite the very high respiratory rates in the hyperthermic pigeon, tidal volume is so reduced that parabronchial ventilation is within a normal range and that no disturbance of acid-base balance results. Salt and Zeuthen (1960) concluded that there was…