Mrs. Jessie Donalda Dunlap was honourary president of the Royal Agricultural Winter Fair for the years 1940 to 1946 inclusive. As the owner of Don-Alda Farms, she encouraged the breeding of Guernsey cattle, beginning with a herd of 20 cows and a bull. These were imported from the Island of Guernsey, and later, additions were made from the best herds in Canada and the United States. Between 1925 and 1947 this herd won a majority of the championships at the major shows. Notwithstanding the splendid reputation, this established breeding stock could always be bought at reasonable prices by young breeders intent on improving their herds.

While Guernsey cattle occupied the spotlight at Don-Alda Farms, Leghorns, ducks, Yorkshire pigs and Clydesdales were raised there as well, and with flowers and vegetables from the gardens and greenhouses, won many awards.

Throughout its period of operations, the facilities of the farm were made available to the Ontario Research Foundation for conducting research studies in brucellosis and mastitis, in feeding and in many other subjects that promised to be beneficial to agriculture.