Detection of quantitative trait loci affecting fertility trait in dairy cattle

Abstract

The objective of this study aimed to investigate the locations of QTL affecting age at first calving andcalving interval in Thai crossbred Holsteins by daughter design. Five sire families with total of 457 daughters weregenotyped for fourty two microsatellite markers with coverage of 7 bovine autosomes. Both of the yield deviationsand the estimated breeding values were used. The putative QTL were scanned every 1 cM within the region coveredby all markers. Ten thousand permutations were used to estimate the 5, and 1% chromosome-wise significancethresholds. The putative QTL affecting AFC and CI were most found linkaged on the same chromosome, which werechromosome 4 (between BMS827-BMS789), chromosome 7 (BM6117-OARAE129), and chromosome 23 (betweenBM1818-DIK4203). However, the QTL affected AFC alone were also found on chromosome 2 (near BL1028), andchromosome 6 (near BMS2508, near DIK2294, and near ILSTS035). EBV was the most suitable data set analyzedfor QTL affecting fertility traits in Thai crossbred.