[QTL mapping for ear shape based on a commercial pig population].

A commercial pig population, including 19 hybrid boars [Piétrain x (Piétrain x Hampshire), 52 hybrid sows [Leicoma x (Large White x Landrace)] and their 332 offspring, was used to construct a reference pedigree, with which a linkage map of whole genome was created using 172 microsatellite markers and three type-1 markers (RYR1, PRKAG3, PIT1). The average of the notes of ear shape (pricky ear shape noted by 1; middle ear shape noted by 0; floppy ear noted by -1) detected by a trained technician is 0.23 and the variation 0.82. QTL mapping for ear shape was carried out with the least square regression method. The result showed that only one QTL for ear shape was detected at 1% genomewise level at the end (between Sw1881 and Sw322) of the chromosome 6 and no QTL was found on the other chromosomes even at 10% chromosome-wise level.