Induction of parturition in mares.

This research investigates the effects of different doses of oestrogen and oxytocin in inducing labor in horses, over a two-year study involving thirty-one mares. The study found that increasing oxytocin doses significantly impacted labor signs and delivery times, while oestrogen primarily influenced the softening and relaxation of the cervix.

Research Purpose and Method

• The core purpose of this research study was to investigate the impact of various doses of hormones, namely oxytocin and oestrogen, on induced parturition (labor and childbirth) in mares (female horses).
• The researchers monitored and analyzed thirty-seven induced parturitions involving thirty-one mares over a span of two years.

Oxytocin’s Role in Parturition

• Oxytocin is a hormone known for inducing labor in many mammals. The research found that increasing doses of this hormone significantly influenced the way labor progressed in the mares.
• Specifically, the time of appearance and the degree to which major clinical signs of labor were expressed were affected. In other words, labor started sooner and was more intense when larger doses of oxytocin were administrated.
• The time required for the completion of delivery and the expulsion of the placenta were also significantly reduced with higher oxytocin dosages.

The Impact of Oestrogen

• The research found that oestrogen, another hormone, had a notable impact on the condition of the cervix during labor. It helped in softening and relaxing the cervix, especially when it was tight, facilitating easier delivery.
• However, the research indicated that oestrogen was not essential for inducing parturition if the mare’s cervix was already soft and beginning to dilate.

Effect on Fertility post Parturition

• A key finding from this research was that induced parturition did not negatively affect the mares’ fertility. This implies that mares can give birth in the future without complications, even if their previous labor was induced.