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A dam line consists of more than 2,000 great-grandparents (GGPS) and grandparent sows (GPS) distributed in minimally 2 herds. Those animals are tested for fertility, robustness, longevity, and maternal traits and produce over 26,000 gilts that are performance tested for growth traits and carcass composition, and relevant selection candidates are genotyped. The sow replacement rate per year is about 150% at the GGPs level, which significantly reduces generation interval. Male selection candidates from litters with a high selection index are selected and genotyped to preselect the highest indexing boars to the Delta central performance test station. Annually, about 60 GGP boars are selected with a high intensity out of the 2500 boars yearly and are performance tested at feed stations and CT scanned. Besides information from the nucleus, data is collected from sows in multiplication herds and commercial crossbred parent sows to also provide additional information on fertility and stayability for selecting the nucleus animals.