Right ventricular heart failure of Montana cattle.

Congestive right ventricular heart failure of Montana cattle is characterized clinically by an accumulation of edematous fluid in the brisket region and ventral portions of the body but not of the legs. A well developed jugular pulse is first observed followed by a watery diarrhea and usually by the accumulation of excessive fluid in the pleural and peritoneal cavities. As the case develops over a period of two to three weeks, the ventral edema becomes more marked (Fig. 1) and straw-colored fluid may accumulate in the body cavities until the abdomen is distended and breathing labored. Death may occur as a result of respiratory failure due to the large volume of pleural fluid or from general debilitation as a result of the right ventricular failure. The incidence of this type of heart failure in Montana cattle is highest on moist mountain valleys. Eighty-one of 113 cases observed over a seven year period occurred in cattle that were maintained at altitudes of 1525 m or below. This paper describes the conditions under which the disease occurs in Montana and compares the hemograms of clinically ill and healthy cattle.