Survival rate and short-term fertility rate associated with the use of fetotomy for resolution of dystocia in mares: 72 cases (1991-2005).

This research explores the survival and short-term fertility rate of mares that underwent fetotomy due to severe dystocia. The study concluded that with high survival rates and similar short-term fertility rates when compared to those of mares that had a cesarean section or controlled vaginal delivery, fetotomy is a safe and effective treatment option.

Study Design and Methodology

• The study was retrospective in nature and carried out over a 14-year period from 1991 to 2005.
• Data was extracted from the medical records of 72 mares that had severe dystocia, which led to the performance of a fetotomy.
• The research team explored several factors, including the presentation and position of the foals, survival rate of the mares post fetotomy, complications that occurred, as well as the short-term fertility rate of the mares.
• A key analysis was done on the 45-day pregnancy rate for mares that were bred 2 to 3 months post fetotomy.

Study Results

• Fetal presentation was anterior in 75% of mares, posterior in 18.1%, and lateral in 6.9%. One fetus had hydrocephalus.
• Post fetotomy survival rate was quite high, standing at 95.8%.
• Certain complications occurred, including retained fetal membranes (5.5%), laminitis (6.9%), vaginal and cervical lacerations (2.8%), and delayed uterine involution (2.8%).
• Mares that were bred 2 to 3 months after undergoing a fetotomy demonstrated healthy short-term fertility, with a 45-day pregnancy rate of 79.4%.

Study Conclusions

• The high survival rate recorded post fetotomy was notable, especially when compared with rates reported after a cesarean section.
• Additionally, the short-term fertility rate post fetotomy was found to be similar to those reported for mares that had a controlled vaginal delivery or cesarean section.
• The research concluded that a fetotomy performed by a skilled veterinarian on a nonviable fetus should be considered a safe and effective solution for correction of dystocia. Moreover, the procedure does not necessarily affect the short-term fertility of the mares involved.