Vol. 85, Issue 3, 1030-1036, September 1998
Blood-gas measurements adjusted for temperature at three sites
during incremental exercise in the horse
L. E.
Taylor,
D. S.
Kronfeld,
P. L.
Ferrante,
J. A.
Wilson, and
W.
Tiegs
Department of Animal and Poultry Sciences, Virginia Polytechnic
Institute and State University, Blacksburg, Virginia 24061-0306; and
Waltham Centre for Equine Nutrition and Care, D-2810 Verden, Germany
Rectal temperature
(Tre) is often used to adjust
measurements of blood gases, but these adjusted measurements may not
approximate temperatures during intense exercise at main sites of gas
exchange: muscle and lung. To evaluate differences in blood gases
between sites, temperatures (T) were measured with thermocouples in the rectum (re), in mixed venous blood (
), in
gluteal muscle (mu), and on the skin (sk) in seven Arabian horses as
they underwent an incremental exercise test on a treadmill. Blood
samples were drawn from the carotid artery and pulmonary artery (mixed
venous) 30 s before each increase in speed and during recovery. Blood gases and pH were measured at 37°C, and all variables were adjusted to Tre,
, and
Tmu. Adjusted variables during
exercise and recovery were significantly different from each other at
the three sites. Linear and polynomial equations described the time
course of venous temperature and
from
Tre and
Tsk during exercise and from
Tsk during recovery.
Interpretation of changes in muscle metabolism and gas exchanges based
on blood-gas measurements is improved if they are adjusted
appropriately to Tmu or
, which may be predicted from
Tsk in addition to
Tre during strenuous exercise and
from Tsk during recovery.
Arabian horses; muscle temperature
