The Shorthorn breed of cattle, developed on the northeastern coast of England before 1750, is the most universally attributed breed in the world. Introduced to America about 1783 but not brought to Texas until the 1850s, Shorthorns were the first purebred animals used by Texas ranchers to improve their Longhorn stock. Mortality among the early Texas Shorthorns was high because of Texas fever, but ranchers, impressed with improvement of their herds, continued to import high-grade bulls. The seventy-five purebred Shorthorns purchased by Charles Goodnight for the JA Ranch in 1876 were largely responsible for the breeding up of Texas Panhandle stock. Charles Mulhern, who established a ranch near Fort Davis in 1878, was an extensive Shorthorn breeder. In South Texas, Robert J. Kleberg, of the King Ranch, was one of the first to introduce purebred Shorthorns into the Texas fever area. His losses were high until the process of immunizing northern cattle was developed. Frank Scofield of Hillsboro developed a Shorthorn herd that supplied many of the state's top registered cattle between 1900 and 1907. Shorthorns mature early and put on weight rapidly. Originally they were good milkers, but in range areas the milk-producing ability has been largely bred out. The animals may be red, white, roan, or mixed red and white in color. Bulls weigh from 1,800 to 2,200 pounds or more. Cows weigh an average of 1,800 pounds. Although the Shorthorn has never attained the Hereford's popularity in Texas, the breed laid the foundation for the state's improved stock. In many cases Texas herds were well graded up with Shorthorn blood before Herefords were introduced. Shorthorns have done very well in crossbreeding programs, most notably in the development of the Santa Gertrudis breed on the King Ranch. In 1946 the breed was estimated to comprise from 5 to 10 percent of Texas beef cattle. The American Shorthorn Association is headquartered in Omaha, Nebraska, and the Texas Shorthorn Association office is at Olton, Texas. In 1986 there were approximately thirty-six Shorthorn breeders in Texas.