Abstract:

【Objective】 The whole genome scanning strategy was employed to locate the quantitative trait loci (QTL) for eight porcine body-dimension traits, including body length, body height, cannon circumference, chest circumference, chest width, chest depth, abdominal circumference and hunkers circumference. 【Method】 A total of 129 F2 animals from a White Duroc × Erhuanlian resource population were measured for the eight traits mentioned above at 210 days of age. All of the 129 F2 individuals and their parents and grandparents were genotyped for 183 informative microsatellite markers across 18 porcine autosomes and the X chromosome. Quantitative trait loci (QTL) for these traits were identified by using an composite interval mapping method based on least-squares regression, which was performed by online software of QTL Express. Meanwhile, the threshold values were determined by an experiment-wise permutation of 1 000 iterations. 【Result】 A total of 19 QTLs were detected for the seven traits on 8 chromosomes, including five 1% genome-wide QTLs on SSC4 and SSC7 and two 5% genome-wide QTLs on SSC2 and SSC7. None QTL was identified for chest width. 【Conclusion】 Most of QTLs located in different chromosomes, and the phenotypic variance explained by each QTL ranged from 5.23% to 41.58%. The favorable alleles of some QTLs originated from White Duroc, but the others were from Erhualian.

Key words: pig, body dimensions, QTL mapping