A quantitative study of the aorta of the chicken (Gallus domesticus).

The different segments of the aorta were studied quantitatively in five age groups of chicken. It was observed that the widest diameter and the thickest media occur on the 56th day in each segment, except for the thoracic aorta, which had the widest diameter on the 42nd day and the thickest media on the 70th day. The percentage of the intima, media and the adventitia, as compared with the total wall thickness, was determined and it was found that this value was quite similar in age group, but the differences were significant from one segment to another. The ratio between the total wall thickness and the lumen diameter was also calculated in each segment.