Most cattle in the United States--by a four-to-one margin--are bred for beef. Beginning with grasses growing on the pastures and ranges, beef cattle eventually are fattened in feedlots on high-grain rations to yield high-quality carcass beef. The British breeds of Angus, Hereford and shorthorn make up a large part of the beef cattle population. In almost half the states, the cattle industry ranks as a primary source of farm income. The number of cattle raised and the prices at which they sell vary widely from year to year.