On September 6, 1975, one cow in a herd of 36 near Aplington, Iowa, was found by the owner as being slow and weak. Dr. Eldon Uhlenhopp was called to examine the cow. The cow's mucous membranes were found to be very pale and icteric. She also had a temperature of 100F. Hemoglobin was determined to be 3 gm %. A differential diagnosis of anaplasmosis or leptospirosis was made.