このデータセットの列幅(3列すべて)を次のように設定します。anim= 1-10; sireid = 11-20; damid=21-30。一部の列に値がありません。
anim=c("1A038","1C467","2F179","38138","030081")
sireid=c("NA","NA","1W960","1W960","64404")
damid=c("NA","NA","1P119","1P119","63666")
mydf=data.frame(anim,sireid,damid)