Performance Data Glossary

The data used in this contest is intended for educational purposes, and is not the actual data for the pigs pictured. The figures accompanying the pictures will be used by our official judges, however, to determine the official placings. Listed below is an explanation of terms used in the contest.

EXPECTED PROGENY DIFFERENCE (EPD) - An EPD is the best estimate of a sire or dam's genetic worth, given the information available. It is the actual difference in performance a producer can expect from future progeny of a sire or dam relative to the future progeny of an average tested parent. Positive EPDs are more desirable for number born alive, 21-day litter weight, and pounds of lean. Negative EPDs are more desirable for days/250 and backfat.

EPD NUMBER BORN ALIVE (NBA) - Predicts the number born alive for each individual's progeny relative to an average tested pig. A sow with an EPD of +.5 would be expected to produce daughters that would farrow litters with .5 more pigs than an average tested sow.

EPD 21-DAY LITTER WEIGHT (LWT) - Predicts the 21-day litter weight for an animal's progeny. A sow with an EPD of +3.4 would be expected to produce daughters which would produce litters 3.4 pounds heavier at 21 days than an average tested sow.

SOW PRODUCTIVITY INDEX (SPI) - An index for reproductive traits that combines number born alive and 21-day litter weight. Ancestral data and a sow's lifetime data are included in her SPI.

EPD DAYS/250 (DAYS) - Predicts performance of the offspring of an animal. A boar with an EPD of -3.0 would be expected to produce progeny that would reach 250 pounds three days faster than an average tested boar.

EPD BACKFAT (BF) - Predicts backfat of the offspring. A boar with an EPD of -.04 would be expected to sire pigs .04 inches leaner than an average tested boar.

EPD POUNDS OF LEAN (LBS.) - Pound of fat free lean adjusted to a 185-pound carcass. A boar with an EPD of 3.0 would be expected to sire offspring with 3 more pounds of lean than an average tested boar.

MATERNAL LINE INDEX (MLI) - This index weights EPDs for both terminal and maternal traits relative to their economic values, placing approximately twice as much emphasis on reproductive traits relative to post-weaning traits.

TERMINAL SIRE INDEX (TSI) - This index combines growth, pounds of fat free lean, and backfat. Selection on this index is appropriate to use to select boars for use as terminal sires in a crossbreeding program.

Swine Testing And Genetic Evaluation System (STAGES) - A genetic evaluation system provided to the members of the four breed associations of the National Swine Registry. STAGES utilizes performance records for Growth, Backfat, Pounds of Lean, Litter Size, and Litter Weight to predict the genetic value of each pig and it's parents.