Arnold S. "Rosy" Rosenwald, extension poultry pathologist emeritus at the University of California, Davis, whose career and contributions to poultry medicine spanned more than 70 years, died Jan. 23 in Davis at age 98. A memorial service is being planned for late February.

"For more than 30 years after his retirement, Dr. Rosenwald continued to play an active role in maintaining a collegial network of professionals in industry and academia," says Carol Cardona, extension poultry veterinarian at UC Davis. "Almost anywhere you go in the world, poultry veterinarians know Rosy."

Dr. Rosenwald was born in 1909, in Albuquerque, in what was then territory of New Mexico. He attended UC Berkeley and UC Davis, earning a bachelor's degree in 1930. He completed his doctor of veterinary medicine degree at Kansas State University in 1936, and went on to earn a master's degree in bacteriology from Oregon State University in 1942, and a doctorate in veterinary science from the University of Wisconsin-Madison in 1956.

Between 1930 and 1937, he worked for the U.S. Department of Agriculture inspecting red meat, investigating swine brucellosis and sheep scabies and testing sheep for tuberculosis. He then served, from 1937 until 1942, as an assistant professor of veterinary science and assistant veterinarian in the Agricultural Experiment Station at Oregon State University.

Between 1942 and 1946, Rosenwald was a veterinary officer with the rank of captain in the Veterinary Corps of the United States Army, where he served as a veterinary bacteriologist for the War Department's Special Project Division and cared for the veterinary needs of the birds in the Signal Pigeon Corps.

In 1946, he initiated the Extension Poultry Disease Program when he accepted a job as the first extension poultry veterinarian at the University of California, serving at UC Berkeley for four years and then at UC Davis from 1950 until he retired in 1977.

"I don't believe there was a person trained in poultry at any level at UC Davis who didn't have Rosy as a part of their training program--he was just that influential," says Arthur Bickford, former associate director of the California Animal Health and Food Safety Laboratory in Turlock. "The energy he had was pure dedication."

During his career, Rosenwald emphasized the importance of poultry veterinary medicine and of poultry as human food, and in addition to clinicians, saw managers, consultants, diagnosticians and poultry disease researchers as practitioners of the art and science of veterinary medicine.

In a 1989 article for the Journal of the American Veterinary Medical Association, Rosenwald wrote, "Poultry practice set the pattern for the role of herd animal medicine in today's production of animal food for human beings."

He wrote that early in his career, "The lessons I learned were to be cautious, carefully interpret findings, and depend on flock history as a guide to find correct answers. I learned the value of the phrase 'I don't know.' " He would follow with, "But I'll darn sure try to find out."

"He was the first person I knew of from the university to come down to Modesto to talk to the members of the poultry industry at the Ag Extension office--he was extremely informative about poultry diseases," recalls Jim West of the J.S. West Milling Company, a member of the Pacific Egg and Poultry Association. "The industry is losing one of our finest teachers and one of my earliest mentors."

Rosenwald served on the 1959 committee of the National Academy of Sciences National Research Council to develop Methods for the Examination of Poultry Biologics, the first report of its kind.

He was a charter and life member of the American Association of Avian Pathologists and served in multiple roles, including president, secretary-treasurer, publicity officer, and editor of Avian Diseases from 1961 to 1965.

He was a founder of the Western Poultry Disease Conference established in 1951 to exchange ideas and promote effective, coordinated poultry health measures. Rosenwald is credited with making that meeting a renowned international conference on avian diseases. He was instrumental in initiating, in 1967, the industry-oriented Poultry Health Symposium, jointly sponsored by the conference and the Cooperative Extension.

Colleagues recall that his hobbies were this conference and people, particularly other veterinarians and especially those who know the value of feathered animals for the welfare of human beings.

"Rosy will continue to be an inspiration to all who have known him," says Donald Klingborg, director of Veterinary Medicine Extension and associate dean for public programs at the UC Davis School of Veterinary Medicine. "He gave unselfishly of his time and incredible knowledge, brought people together to create effective networks and accomplish important tasks and contributed significantly to others to the end. He was a gentleman's gentleman, had an infectious smile and inquiring mind, and helped people achieve more from themselves with his presence. He is missed."

"I will fondly remember him for his encouragement and generosity," says Carol Bates, manager of Poultry Veterinary Services in Auckland, New Zealand. "He was a master at networking and helping people by putting them in touch with each other. I am sure I am not the only student of poultry science to have benefited from his wise counsel and collegiality."

Colleagues and friends expressed their esteem for Rosenwald by raising funds to dedicate a classroom in his name in the new School of Veterinary Medicine instructional facility, Gladys Valley Hall, which opened in 2006.

He was honored in 2005 as Poultry Scientist of the Year by the Pacific Egg and Poultry Association and received the Distinguished Service Award of the American Association of Avian Pathologists in 1980. He was named the 1975 Extension Veterinarian of the Year by the American Association of Extension Veterinarians, and he received a Citation for Outstanding Achievement from the American Association of Avian Pathologists in 1969. In 2000 the avian pathologists association recognized his efforts to advance avian medicine by initiating the A.S. "Rosy" Rosenwald Student Poster Award, a competitive scholarship, which is presented to the best student poster at each annual meeting.

Rosenwald is survived by his wife, Joan; daughter, Joyce Rosenwald of Corvallis, Oregon; grandson Todd Nelson of Fresno, Calif.; and his stepdaughter and her husband, Pat and Rich Nims of Hawaii. He was preceded in death by his brother, Stanley; his first wife, Genevieve; and daughter, Joan.

In lieu of flowers, donations in his memory may be sent to the American Association of Avian Pathologists to support the A.S. "Rosy" Rosenwald Student Poster Award, 953 College Station Rd., Athens, GA 30602-4875.

More information about the pending memorial service can be obtained from the UC Davis Veterinary Medicine Extension, (530) 752-1524.