In 1913 in South Park, Colo., a strange disease in beef cattle was investigated by two CSU researchers, George Glover and Isaac Newsom, in response to requests from two producers, Lew Robbins and David Collard. The problem became known as brisket disease, or high-altitude disease, because it affected cattle at high altitudes and led to fluid accumulation in the tissues under the chest and often led to death. The researchers conducted clinical investigations and determined that the low level of atmospheric oxygen experienced at high altitude was the primary cause of brisket disease. How can this be? The pulmonary arteries exit from the right side of the heart and carry deoxygenated blood returning from the body to the lungs for re-oxygenation. The low level of oxygen in the air at high altitude causes these arteries to contract. This contraction in response to low atmospheric oxygen tension is greatest in cattle