When you’re a commercial producer using two or more breeds in a rotational cross breeding program, it’s almost impossible to evaluate the animals on the same level. Expected progeny differences vary significantly between breeds because each breed has a different base point. But using the table of adjustment factors can help you estimate across-breed EPDs.

For example, if a Gelbvieh bull has an EPD for weaning weight of +25 and a Hereford bull has an EPD of +25.0, would you expect their progeny out of a different breed of dam to weigh about the same? No, the adjustment factors are different. In this case the across breed EPD for the Gelbvieh bull would be 45, which has the table adjustment factor of 20 added to the Hereford EPD of 25.0. In this example, progeny of the Gelbvieh bull would be expected to weigh, on average, 18 pounds to 20 pounds more at weaning than progeny of the Hereford bull (20 + 25.0)-(2+25)=18 pounds. (See chart, right.)