The Impact of the Cavitary Corpus Luteum on the Blood Progesterone Concentration and Pregnancy Rate of Embryo Recipient Heifers

In cattle there are two types of the corpus luteum (CL): homogeneous (CLhom) and cavitary (CLcav). Although they are considered equal in their hormonal activity, the function of the CLcav is questioned by many veterinarians. In consequence, females with the CLcav are considered less valuable for assisted reproductive techniques such as embryo transfer (ET), where recipients with the CLhom are preferred. The aim of our study was to compare the two types of CLs regarding morphological endpoints, serum progesterone (P4) concentrations and final pregnancy rate (PR) in recipient heifers after ET.