Impacts of placentitis on mare gestation
DOI:
https://doi.org/10.31533/pubvet.v19n10e1854Keywords:
placental diseases, placental infection, reproductive pathologyAbstract
Placentitis is one of the leading causes of pregnancy loss in mares, being responsible for abortions, premature births, stillbirths, and the delivery of weakened or septic foals. It is an inflammation of the placenta, generally of infectious origin, with ascending infection by Streptococcus zooepidemicus being the most common. Other types include nocardioform, hematogenous, and multifocal placentitis, which differ in pathogenesis, location, and causative agents. Predisposing factors such as advanced age, multiple pregnancies, and poor perineal conformation facilitate the entry of microorganisms into the uterus. The disease impairs placental function, compromising the supply of oxygen and nutrients to the fetus and leading to altered fetal development. Diagnosis is based on clinical signs, hormonal testing, and ultrasonography, with the transrectal approach indicated for ascending cases and the transabdominal approach for nocardioform types. Treatment aims to prolong gestation and improve fetal prognosis, using antibiotics, anti-inflammatory drugs, and progestagens. However, the therapeutic response varies depending on gestational age and disease severity. Early detection is essential to reduce reproductive losses and improve neonatal outcomes. This literature review summarizes the main aspects related to the etiology, diagnosis, gestational impacts, and management of placentitis in mares.
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