In the first day's MRI scan you may not be able to see very much, but the image might look like these. Yolk formation takes about 18 days. During the last 7 or 8 days of yolk development, the yolk is deposited in layers like the rings of a tree. These layers are visible in your MRI images. In the MRI images, yellow yolk appears dark.
White yolk is low in fat and is formed during the night.
The white yolk appears as narrow, white bands on the MRI images.