Selection is the main principle at Fidel San Román Stockbreeding. Their cattle's purebred and fierceness are guaranteed by generations of excellent specimens.

They have several thoroughbred studs of different ages, which crossbreed with selected cows for producing the specimens of maximum quality and fierceness.

The cows are selected at their modern bullring, the traditional way: through the examination of their mobility, firmness, attack, horse undertake, deceive, nobility and strength. If they pass this rigorous test, they'll become part of the selected herd to engender the successive litters.