Figure 2.

Difference in egg production between dark comb and red comb chickens during laying period. (A) Difference in the number of eggs recorded from weeks 17 to 60 obtained from an experimental farm in the China Agricultural University; The coordinate 2013b indicates the comparison between dark comb line (DCL) (N = 30) and red comb line (RCL) (N = 86); The coordinate 2013c indicates the comparison between dark comb layers (N = 48) and red comb layers (N = 14) from the random line (RAL). (B) Difference in the number of eggs in a large population (N = ∼500) in different generations (data obtained from the conservation farm of Dongxiang blue-shelled chicken); the number of eggs were recorded for 4 months (2011a, 2013a) and 2 months (2014a). The coordinates 2011a, 2013a, and 2014a indicate different generations from the conservation farm. ***p < 0.001, **p < 0.01.