Santa Gertrudis were developed on King Ranch to function in hot, humid, and unfavorable environments. The Santa Gertrudis was developed by crossing Indian Brahman cattle with British Shorthorns. In 1920, years of experimentation culminated with the birth of Monkey, a deep red bull calf. Monkey became the foundation sire for not just a superior line of cattle, but an entirely new breed. In 1940, Santa Gertrudis was recognized by the U.S.
Department of Agriculture as the first beef breed developed in the United States. Even today Santa Gertrudis are referred to as America's original beef breed.
Santa Gertrudis cattle are approximately five-eighths Shorthorn and three-eighths Brahman. They are a deep cherry-red color with a relatively high degree of both heat and tick resistance. Santa Gertrudis females are known for their exceptional maternal traits. Their characteristics include ease of calving, good mothering ability and abundant milk supply.