Heat storage in running antelopes: independence of brain and body temperatures.

TAYLOR, C. RICHARD, AND C. P. LYMAN. Heat storage in running antelopes: independence of brain and body temperatures. Am. J. Physiol. 222(l): 114-117. 1972.-Tremendous amounts of heat are produced when antelopes run at high speed. This study tried I) to determine how much of this heat was stored, and 2) to find out if antelopes possess unusual physiological mechanisms for coping with high body temperatures. Large increases in rectal temperature of Thomson’s gazelles (Gasella thomsonii, wt 15 kg) were measured during running : + 3.9 C after 5 min at 40 km hr-1; +4.6 C after 11 min at 25 km hr-l; and +4.3 C after 20 min at 15 km hr? Heat storage accounted for 80-989;‘, of the calculated heat production during running. Brain temperature rose more slowly than rectal or carotid artery temperature. After a 5 min run at 40 km hr-r the brain was 2.7 C cooler than blood in the carotid artery. Blood supplying the brain appears to be cooled via a countercurrent heat exchange with cool blood draining the nasal mucosa (in the carotid rete). Elands (Taurotragus oryx, wt 200 kg) sweated profusely and their rectal temperature equilibrated after a few minutes of running at a slightly higher level: +0.8 C at 25 km hr-l; +0.8 C at 20 km hr-l; +0.7 C at 15 km hr-l; and 3-0.5 C at 10 km hr?