摘要： Jinyang Ⅲ strain of late-feathering Leghorn chicken has been successively selectedwith comprehensive index for 7 generations by family breeding method of mass-first and closing-late.As compared with the control,the selection result is average 7 days earlier at first laying forevery generation,more than 13 of egg number at age of 300 days and higher than 0.63% for sur-vival rate in laying period.Main laying performances are as follows:age at first laying 156±10.4days;egg number at age of 300 days 99±26.O;egg number and egg weight at 72 weeks of age 226±38.8 and 58.2±4.6g respectively.Through cross breeding selection,a series of white-shell au-tosexing chicken has been developed.More than 5.1 million commercial sex-identified chickenhave been released as well.

关键词: chicken, Jinyang white Leghorn, late feathering, selection