The Embryonic Development of the Equine Heart*

Equine cardiogenesis was studied in embryos of approximately 21 to 49 days of gestation, with particular attention to the partitioning of the ventricular outflow channel. Timing of several morphogenetic events associated with this partitioning was recorded in Table 1. Present investigation indicated that partitioning of the ventricular outflow channel into the pulmonary trunk and aorta was already completed at about 36th to 38th day of gestation. Results of this study may aid in better understanding of the congenital malformations, especially those associated with great vessels of the equine heart.