siRNA-mediated knockdown of chicken NANOG in chicken embryonic stem cell-like cells shows severe changes in morphology. (A) After 48 hr of chicken NANOG knockdown, chicken embryonic stem cell-like cells were monitored at 6 hr intervals for up to 48 hr. The white dotted circle indicates damaged chicken embryonic stem cell-like cells. Scale bar: 100 μm. (B) The endogenous Pou5f3 and Sox2 genes in chicken embryonic stem cell-like cells after 48 hr of chicken NANOG knockdown were significantly decreased compared to the control. All data are expressed as the mean ± standard error from three independent experiments. A p value <0.05 was considered to indicate statistical significance.