Fig. 2From: Analysis of polygenic selection in purebred and crossbred pig genomes using generation proxy selection mappingDistributions of AGE for genotyped pigs in Duroc, Landrace, Yorkshire and crossbreed lines. For each Duroc (a), Landrace (b), Yorkshire (c), and crossbred (d) pig, AGE was calculated as the number of months between each pig’s birth month and January 2006. For example, a pig with an age of 120 was born in January 2016Back to article page