Arterial anatomy of chicken embryo and hatchling.

The arterial pattern in chicken hatchlings was investigated by microangiography and microscopic analysis of cleared specimens. The hatchling arterial pattern was found to resemble strongly the pattern that has been described for the adult chicken. Several minor variations in this pattern were found which were probably due to species, strain, or age differences. We also investigated the arterial pattern in chicken embryos aged 4.5 to 21 days of incubation. The hatchling pattern was fully developed by approximately 8 days of incubation. Some similarities were found to exist between the embryonic pattern in the chicken embryo and that described for the human embryo.