Frederick Banting upon the idea of obtaining insulin from the fetal pancreas. He removed the pancreases from fetal calves at a William Davies slaughterhouse and found the extracts to be just as potent as those extracted from the dog pancreases. By December 1921, he had also succeeded in extracting insulin from the adult pancreas. Pork and beef would remain the primary commercial sources of insulin until they were replaced by genetically-engineered bacteria in the late 20th century. In spring of 1922, Banting established a private practice in Toronto and began to treat diabetic patients. His first American patient was Elizabeth Hughes Gossett,
Frederick Banting and Labrador is a museum named after him which focuses on the circumstances surrounding the 1941 plane crash which claimed his life. The crater Banting on the Moon is also named after him for his contributions to medicine. During the voting for "Greatest Canadians" in late 2003, controversy rose over the future use of the Banting family farm in New Tecumseth which had been left to the Ontario Historical Society by Banting's late nephew, Edward, in 1998. The dispute centred on the future use of the 40 ha (100 acre) property and its buildings. In a year-long negotiation, assisted by