Dr. Ernest S. Tierkel, 64, a retired assistant surgeon general who served in the Public Health Service for 27 years before retiring in 1973, died Nov. 2 at Bethesda Naval Hospital following cardiovascular surgery.

Dr. Tierkel was assistant surgeon general from 1968 until his retirement. During these years he also was the PHS's chief veterinary officer and an assistant to an assistant secretary for health and scientific affairs in the old Department of Health, Education, and Welfare.

He moved to Dover, Del., in 1973 and joined the staff of the Delaware Department of Health and Social Services. He was chief of the disease control bureau in the Department's public health division at the time of his death.

Dr. Tierkel was a consultant to the Pan American Health Organization and a diplomate of the American College of Veterinary Preventive Medicine.

He was a native of Philadelphia and graduated from the University of Pennsylvania, where he also earned his doctorate in veterinary medicine. He earned a master's degree in public health from Columbia University.

He began his career with the Public Health Service in 1946 in Atlanta, where he was director of the National Rabies Control Program. In 1964, he joined the Agency for International Development in Washington. From 1966 to 1968, he was chief of AID's communicable disease control branch in New Delhi.

Survivors include his wife, Ruby, and a son, David, both of Dover; a stepson, Army Lt. Col. Michael Steele of Fort Bragg, N.C.; a brother, a sister, and two grandchildren.