Table 1.

Total number ± SEM of circulating red blood cells (RBCs) and of primitive red cells in E12.5, E14.5, and E16.5 mouse embryos




Total RBCs, × 106 per embryo

Primitive RBCs, × 106 per embryo

Nucleated primitive RBCs, %

n
E12.5   5.3 ± 0.9   4.8 ± 0.6   91.2 ± 4.3   3  
E14.5   26.3 ± 6.9   6.0 ± 2.2   22.6 ± 9.4   3  
E16.5
 
151.7 ± 28.6
 
10.8 ± 4.5
 
6.5 ± 2.0
 
4
 



Total RBCs, × 106 per embryo

Primitive RBCs, × 106 per embryo

Nucleated primitive RBCs, %

n
E12.5   5.3 ± 0.9   4.8 ± 0.6   91.2 ± 4.3   3  
E14.5   26.3 ± 6.9   6.0 ± 2.2   22.6 ± 9.4   3  
E16.5
 
151.7 ± 28.6
 
10.8 ± 4.5
 
6.5 ± 2.0
 
4
 

There are no significant changes in the numbers of primitive red cells as they enucleate between E12.5 and E16.5. n indicates the number of independent experiments.