The cavitary corpus luteum: opportunity or threat for bovine reproduction?

The homogenous, compact or non-cavitary corpus luteum (CL) is an ovarian structure appearing after ovulation and responsible of progesterone synthesis during the estrous cycle and pregnancy. The cavitary CL is similar to the homogeneous but it presents a more or less developed central cavity. The prevalence of a cavitary CL ranges from 18 to 79% during the period of 6 to 12 days post-ovulation. Most cavities regress throughout the cycle. This review aims to present the state of art of the prevalence, physio-morphological characteristics, diagnostic methods and effects on fertility of the cavitary corpus luteum, most of the aspects remaining a topic of debate. From a clinical perspective, the presence of a CL with a large cavity with a very thin wall, resembling an ovarian follicular/luteal cyst, in absence of a further CL in pregnant cows is also described.