Accessory Corpus Luteum.
This ovary shows a fully developed corpus luteum (left one-third of the ovary) and the papilla of a (3-day old) corpus hemorrhagicum. This is not a natural or spontaneous occurrence. Cows do not ovulate in the face of elevated progesterone concentrations. However, dominant follicles, in the presence of a corpus luteum, can be made to ovulate by the administration of exogenous GnRH or LH, and create an accessory CL.
Drost M (1970)