Ultrasonography as an adjunct to pregnancy assessments in the mare.

The research conducted extensive ultrasonic studies on 952 pregnant Thoroughbred mares. The researchers were able to create images which allowed them to determine details such as twin pregnancies and the comparison of horizontal and vertical diameters exhibited no significant differences. They found that ultrasound evaluations were useful in confirming the mechanical destruction of a twin blastocyst.

Methodology and findings

• The study performed ultrasonography, a non-invasive method of imaging, on 952 Thoroughbred mares. It allowed researchers to visualize the horses’ uterus.
• Characteristic images were obtained between 12 to 55 days after breeding, helping identify key early stages of pregnancy.
• The researchers were able to identify instances of twin pregnancies, regardless of whether the twins were in the same or opposite uterine horns.
• During the first few months of gestation, the researchers observed that twin pregnancies appeared similar to single pregnancies.
• Researchers used the horizontal diameters of the blastocysts and breeding dates to develop growth curves.
• No significant differences were found when comparing horizontal and vertical diameters of the blastocysts suggesting uniform growth.

Additional findings

• Its important to note that the growth curves derived from twins did not show significant differences from those for single pregnancies. It indicates the technique’s sensitivity to distinguish different pregnancies.
• Ultrasonography was extremely helpful in confirming instances of mechanical destruction of one of the twin blastocysts. It refers to an event when one of the embryos in a twin pregnancy does not survive.
• The researchers were also able to visualize uterine artifacts, such as endometrial and lymphatic cysts, on these ultrasonographic images.
• However, these structures were a source of false-positive results. But by studying their morphometric and growth characteristics, they were appropriately identified, reducing the probability of making a false diagnosis.

Significance and Conclusion

• The findings of this study underscore the utility of ultrasonography as a valuable tool for pregnancy assessment in Thoroughbred mares.
• It is not simply able to detect pregnancies, but determines twin pregnancies and other uterine conditions that could interfere with successful gestation.