Types of colic and frequency of postcolic abortion in pregnant mares: 105 cases (1984-1988).

The research article reviews cases of pregnant and non-pregnant mares dealing with colic and its impact on pregnancy outcomes, focussing on survival rates, abortion rates, severity of colic, treatment methods, and other factors that might have influenced the outcome like gestation stage, anesthesia duration, or intraoperative hypoxia or hypotension.

Overview of the Study

• The study examines the case records of 105 pregnant mares and 105 nonpregnant horses, all of whom were treated for colic at an equine hospital.
• All horses, pregnant or not, had similar types of colic and short-term survivability.

Colic Treatment and Outcomes

• Of the 105 pregnant mares, 31 were treated with medication and 74 underwent surgical intervention.
• Unfortunately, 33 mares either died or had to be euthanized.
• Of those that survived, 13 (18%) of the remaining 72 mares ended up aborting their foals.

Medical Cases and Their Outcomes

• The study also breaks down the numbers by the severity of colic treatment needed and the subsequent outcome.
• In the four severe medical cases, outcomes included two deaths, one abortion, and one case where the mare both aborted and died.
• However, of the 27 lesser severe medical cases, none of the horses died and only two resulted in abortion.

Surgical Cases and Their Outcomes

• Outcomes for the 74 mares requiring surgery were 45 managing to carry the pregnancy to term (either foaling or abortion).
• From this group, 36 mares (80%) successfully gave birth to a live foal.
• The type of surgical intervention, surprisingly, had no impact on the outcome of the pregnancy.

Other Factors and Their Impact

• Various other factors were also considered, including the gestation stage at the time of initial examination, duration of anesthesia, or the presence of intraoperative hypoxia or hypotension.
• None of these factors were found to have any significant effect on the outcome of the pregnancy.
• However, if hypoxia occurred during colic surgery within the last 60 days of pregnancy, the mares either had abortions or gave birth to significantly compromised foals that did not survive.