The US alpaca breed society AOA has published its 2018 calculation of Estimated Progeny Differences . This year’s analysis included observations for at least one trait on 34,166 hucacaya and 7,936 suri. This translates to 69,408 huacaya and 15,409 suri for a total of 84,817 alpacas with EPDs.
Expected Progeny Differences (EPDs) are calculated for ten traits—nine fleece traits plus birth weight. Fleece data is collected from standardized fiber analysis. Growth and maternal trait data is also collected for the EPD program for birth weight, weaning weight, and birthing ease.
EPDs provide an estimate of the average difference in an individual’s progeny performance as compared to the national herd OR as compared to another individual animal. EPDs cannot predict the outcome of a single breeding, but rather predict the progeny performance on average over a number of progeny. Utilization of EPDs for traits of interest in breeding plans which include selection for desired traits will, over time, move the herd’s performance in the desired direction.
EPDs are ONE tool in a breeder’s toolbox for making informed breeding decisions.
An accuracy is given to each trait on each alpaca that an EPD is calculated for. Accuracy is based on the amount of performance information available on the animal and its connected relatives — particularly the number of progeny analyzed. Accuracy is also based on the heritability of the trait and the genetic correlations with other recorded traits. Hence accuracy is a relative indicator of the confidence you can place in that particular EPD.
An accuracy value is represented by a number between 0 and 1. Accuracy is a relative indicator of the confidence you can place in that particular EPD. The closer an accuracy is to one, the more reliable the EPD value is.