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A simplified example of the use of special lines is a three-way cross often applied in in pig breeding: first, sows of a line selected for number of piglets is crossed with a boar of a line selected for growth. Second, crossbred sows are subsequently crossed with boars of a line selected for carcass quality. The result is a lot of piglets born with a good growth and carcass quality. Around 1970 in a sheep breeding trial, ewes from the Finnish Landrace breed (a breed with a high litter size) were mated to a ram of the Ile de France breed (a breed that can be bred irrespective of the season). This resulted in crossbred ewes with a high number of lambs due to three lambing’s in two years’ time. The sire of the lambs was a ram of the Texel breed famous for growth and slaughter quality.