Menu

Description: Image of a photomicrograph of bovine corpora lutea on day 4 of the estrous cycle. The basement membrane between the granulosa and the thecal cells loses it's integrity near ovulation. After ovulation, the thecal cells collapse into and mix with the granulosa cells, and blood vessels grow among these cells. Large luteal cells are thought to originate from the granulosa cells. Irregularly polyhedral in shape, they are evident as early as day 4, become more prevalent by day 11, and remain a striking morphological feature on days 18 and 20. The small luteal cells are thought to originate from the theca interna. Both large and small cells secrete progesterone, show degenerative changes beginning in some heifers as early as day 18, and completely lose their lutein identity by the day of the following estrus. The micromorphology of the corpus luteum of pregnancy resembles that in mid-cycle.

Resolution: 300x204

File Size: 16.33 KB