What are EPDs all about?
EPDs (expected progeny differences) are a statistical tool for characterizing prior offspring. If EPDs can be defined for key value traits (see our discussion of breeding strategy), they may be useful to compare production potential of animals within a herd. However, statistical tools like EPDs rely on having statistically valid amounts of data, measured by well-controlled methods, for each animal. EPDs work well in industries that meet these conditions. In cattle, for example, a relatively small population of males sire a large number of offspring by virtue of the very popular practice of using mail-order semen. In addition, many traits of interest for cattle are well-defined, and measurement methods for them are controlled by government and industry regulation. As a result, EPDs for bulls are well defined, and supported by statistically valid amounts of data that is measured and reported reliably. In the alpaca industry, most herdsires don’t have statistically significant numbers of
