Molecular sex identification
For the molecular sex identification in the grey partridge, conserved primers were used, namely the 1237L - 1272H pair (Kahn, John & Quinn, 1998) which delineates an intron that varies in size between the two sex chromosomes in most bird species. The total volume of the polymerase chain reaction was 10 μl in which 100 ng of genomic DNA was amplified, using 0.5 unit of Qiagen Taq polymerase, 0.2 mM dNTPs, 1 pmol of each primer, 1.5 mM MgCl2 and 1 μl of 10 X Reaction Buffer. Thermal cycling amplification conditions were as follows: initial denaturation at 95 oC for 5 min, followed by 34 cycles of strand denaturation at 94 oC for 45 sec, annealing at 56 oC for 45 sec and primer extension at 72oC for 1 min and a final 7 min elongation time at 72oC.