[Clinical signs in late pregnant mares].

This study investigates the changes in heart rate, respiratory rate, and body temperature in different breeds of healthy late pregnant mares, and compares them against established reference values.

Background and Methods

• The researchers observed that interpreting basic health indicators like heart rate, respiratory rate, and body temperature can be challenging during the birthing period in mares.
• In response, they conducted daily physical examinations of late pregnant mares to evaluate these parameters and compared them with the standard values provided in veterinary literature.
• They also explored if there were any size-related differences, and if complications like dystocia (difficult birth) or retained placenta influenced these results in larger horse breeds.

Results

• During the final weeks leading to parturition, there was a significant increase in heart rate in all mares, which subsequently decreased post-parturition.
• The respiratory rate also showed a similar trend, increasing before birth and falling afterwards in larger horses.
• All groups exhibited shifts in body temperature during this period, with temperatures rising after delivery.
• The study found that ponies had the highest heart rate, respiratory rate, and body temperature, while larger horses had the lowest respiratory rate.
• Mares experiencing normal births (eutocia) and those undergoing difficult births (dystocia) did not show significant variation in heart rate.
• However, the respiratory rate in dystocia cases was significantly higher on the first day post-parturition.
• While there were differences in the body temperature before (antepartum) and after (postpartum) birth in mares with normal delivery, these changes remained within the standard boundaries.
• For mares that retained their placenta, no significant change in heart rate was observed, but their body temperature was higher a day after giving birth.

Conclusion

• The researchers concluded that these increased parameters during late pregnancy indicate a distinct physical performance period for mares.
• They emphasized the importance of interpreting these parameters in relation to the mare’s reproductive state to promptly diagnose potential disorders, and subsequently determine if any medical intervention is required.