Non-Infectious Abnormal Placenta and Its Association with Obstetric and Neonatal Parameters in Mares

The placenta is responsible for metabolic and gaseous exchange between mares and fetus during gestation. Any placental damage can affect fetal development and/or foal survival. The aim of the study was to describe the histopathological features of non-infectious placentas from Thoroughbred mares. Immediately after foaling, the placentas (n=148) were weighed and samples from nine placental points (cervical star, uterine body, gravid horn, non-gravid horn, bifurcation, amnion, and tree points from umbilical cord) were collected in 10% formalin, processed, and stained using hematoxylin and eosin and periodic-acid-Schiff (PAS) reagents for evaluation under optical microscopy. In addition, the following data were recorded: mare’s age, number of parturition, gestational age, third stage labor (placental elimination time), umbilical-cord length, placental weight and foal weight. [...]