12.5.1.2 Construction and composition of the sire lines (2024)

Each sire line consists of at least 1,000 GGP sows distributed over at least 2 herds. Those sows are replaced each year at a rate of 150% for a short generation interval. They produce about 8,000 gilts that are performance tested for growth. Male selection candidates are 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 performance tested at feed stations and are CT scanned. Moreover, the offspring of each paternal family is slaughtered, and meat quality is assessed. For each nucleus boar, the growth performance and survival of crossbred progeny (F₂) is recorded on Combined Crossbred Purebred Selection (CCPS) farms. Topigs Norsvin is marketing boars of three different sire lines: TN Tempo, a synthetic line originating from the Yorkshire and the Piétrain; the TN Duroc line and the TN Select line, a Piétrain line. The TN tempo and TN Duroc are used in countries requiring medium lean pigs and the TN Select in countries where a lot of emphasis is paid on lean meat.