QTL effect and family structure play important roles for threshold traits as same as quantitative traits, and more full-sib size could improve accuracy and precision of estimates when family size is small under full-half sib family design.

• QTL效应和家系结构依然是影响阈性状QTL检测的重要因素,QTL效率越大,估计精确性越高,随着家系含量和群体规模的增加,检测结果的准确性和精确性呈增加的趋势,当家系含量较小时,在公畜后代数相同条件下,加大全同胞数量可明显提高检测效果;