Nutritional Programming of Intrauterine Development: A Concept Applicable to the Horse?

Human epidemiological observations and studies of experimental animals have shown that low birth weight is associated with adult phenotypes characterized by abnormalities in cardiovascular, metabolic, and endocrine function. In human populations, these changes can lead to overt degenerative diseases such as hypertension and type 2 diabetes. Because fetal growth depends primarily on the nutrient supply, the associations between birth weight and adult phenotype have been linked to poor nutrition in utero. The fetal supply of nutrients and oxygen depends on both the availability of these substances in the mother and the functional capacity of the placenta to supply them to the fetus. This review takes a comparative approach to examining the nutritional programming of adult physiological phenotype in mammals with emphasis on the horse where possible. It considers the role of maternal nutritional state and placental function in these processes and discusses the cellular and molecular mechanisms operating in utero that are responsible for the epigenetic regulation of phenotypical diversity.     

Surgical Correction of Uterine Torsion and Mare–Foal Survival in Advance Pregnant Equine Patients

This article describes the surgical management of uterine torsion by midline celiotomy and cesarean section on 12 mares presented with signs of colic to a teaching veterinary hospital. The mares were either in full term of gestation (n = 7) or in advanced stage of pregnancy (n = 5). Six mares were in first parity. Uterine torsion was diagnosed by per rectal and per vaginal examinations. For surgical intervention, mares were anesthetized using a combination of xylazine (1.1 mg/kg) and ketamine (2.2 mg/kg), intravenously. After intubation, the animals were maintained on halothane (n = 4) or isoflurane (n = 8) inhalation anesthesia. Midline celiotomy was performed, and foals were delivered by cesarean section. In 11 mares, before closing the abdominal wound, the uterus was detorted manually and confirmed for its normal position. Both anesthetic protocols using halothane and isoflurane were found satisfactory for surgical correction of uterine torsion. After long-term follow-up, the study reported 75.0% (9/12) survival rate for mares. One mare was euthanized because of devitalized, necrosed, and adhered uterus to the abdominal wall. Of the nine surviving mares, seven were successfully bred. Three foals were born alive, and only one could survive on long-term basis. Of the nine dead foals, two had umbilical cord torsion.