Based on the results of our previous (Hamidu et al., 2010) and current studies, we suggest that the reduction in blastodermal cell numbers after egg storage for 4 to14 d could possibly be the reason for decreased embryo quality and poor embryonic performance in eggs stored for a longer duration (Mather and Laughlin, 1977; Fasenko et al., 1992, 2001; Fasenko, 2007). It is interesting that the amount of early apoptotic cell death was higher in broiler breeders. Because apoptosis is a metabolically active cell death mechanism, it will lead to a reduction in energy in embryos that experience a higher amount of apoptosis.