i6 
Colorado Experiment Station. 
respect, thus explaining the high mortality in calves? That is, as 
we look upon the problem, it requires a stronger heart to carry an 
animal through the vicissitudes incident to an existence at a high 
altitude than it does at a low one. Some hearts, in fact most of 
them, have sufficient reserve force to meet the new conditions, as is 
evidenced by the rather common observation that hearts of cattle 
at high altitudes are heavier and thicker (hypertrophy) than those 
lower down. Some animals, however, do not have this reserve 
force and exhaustion of the heart with dilatation results. Such an¬ 
imals would undoubtedly give rise to a certain number of offspring 
whose hearts would be insufficient to meet the vigorous conditions. 
CASE REPORTS. 
CASE No. 1.—Black and white cow, age seven or eight; weight nine 
hundred and fifty. History—Noticed to be ailing the previous summer; 
swelling appeared under jaw about three weeks before; later, swelling 
of the brisket. About the 2 7th of March she refused food for a couple of 
days. On March 30 the swollen brisket was lanced, after which she seemed 
to improve, and drank more water than usual. Seen on April 5, 1913, 
near Jefferson, Colorado; altitude nine thousand feet; in fair flesh; rather 
wild, so that restraint was resisted and only accomplished after much 
excitement on the part of the animal. Following this, the temperature 
was 103° F.; respiration rapid with whistling sounds in trachea. An at¬ 
tempt was made to tap the swelling under the jaw without results. There 
was no weakness, feces very thin, and watery discharge from the nostrils, 
owner thinks animal better. One cubic centimeter of blood was removed 
from the jugular vein and injected into the jugular vein of a healthy 
steer. Cow remained in poor condition throughout the summer and wap 
shipped out in the fall, passing from observation. 
CASE No. 2.—Hereford steer, short, yearling, South Park, altitude 
nine thousand feet, raised there. History—Noticed to he sick about a 
week previous; seen on April 6, 1913, in fair state of flesh; respiration 
not labored hut slightly increased, moist cough; temperature 102.6; ap¬ 
petite good; feces quite thin and dark in color; no mucous or blood; 
brisket swollen and flabby; April 7th, temperature 101.9. Calf eating, 
appears strong. Brisket swollen more than on day previous and rather 
more firm on pressure. Diarrhoea marked, feces dark in color. Abdomen 
enlarged. April 8th, increase in swelling of brisket with thickening of 
lower part of neck. Diarrhoea continues. Temperature 102.5. Jugular 
pulse well marked. April 9th, symptoms same as on previous days. 
Temperature 101.8. Slaughtered for examination. Post mortem exam¬ 
ination.—Large edematous area at the brisket estimated to be ten inches 
long by eight inches wide. About three gallons of straw-colored fluid 
in the thoracic cavity. Considerable in the pericardium. Large blood 
clot the size of one’s fist in the right lung near the dorsal part and just 
above the point where the bronchus enters. Collapsed red areas in the 
apical and cardiac lobes near the lower margin. By far the larger part 
of the lungs appear normal. 
Estimated three gallons of fluid in the abdominal cavity. Mesentery 
very much thickened throughout its whole extent. Fluid can he easily 
squeezed out. Large blood clot near anterior mesenteric artery. Several 
small hemorrhages under the serous membrane. Liver enlarged and 
hard, on section is mottled gray. Spleen normal. Interior of rumen 
and reticulum black. Folds in the fourth stomach very edematous. 
