Impact of equine assisted reproductive technologies (standard embryo transfer or intracytoplasmic sperm injection (ICSI) with in vitro culture and embryo transfer) on placenta and foal morphometry and placental gene expression.

The research focuses on the impact of assisted reproductive technologies (ARTs) such as standard embryo transfer and intracytoplasmic sperm injection (ICSI) on placental and foal development in horses. The study found no significant changes in foal or placental dimensions, or in the expression of particular placental genes examined, due to the use of these ARTs.

Objective of the Study

• The study aimed to examine the effect of Assisted Reproductive Technologies (ARTs) such as standard Embryo Transfer (ET) and IntraCytoplasmic Sperm Injection (ICSI) coupled with in vitro culture and ET on foal and placental genomics and morphometry in horses.
• This research emerged out of the lack of information available on how these reproductive technologies impact fetal and placental development in horses.

Methodology

• The researchers evaluated the morphology of the neonatal and placental in three groups of reining- and cutting-type American Quarter Horse foals (30 in total) based on their conception methods; Naturally Conceived (NC), through Embryo Transfer (ET), or ICSI coupled with in vitro culture and ET (ICSI-C).
• Furthermore, the expression of specific mRNA, for 17 genes linked to growth and vasculature, was studied in the placenta of the different groups.

Results of the Study

• The only significant difference found between the groups studied was the length of the upper hindlimb of the foals, which was found to be longer in foals from the ET and ICSI-C groups than those naturally conceived.
• No observable difference was found in the expression of the 17 genes in the placenta across the different groups. This indicates that the utilization of the ARTs had no significant impact on the expression of genes associated with growth and vascularisation.

Conclusions of the Study

• The study concludes that there were no meaningful alterations in foal or placental dimensions and placental gene expression when ARTs methods like standard embryo transfer and intracytoplasmic sperm injection with in vitro cultivation were employed.
• The findings suggest that these ARTs can be used safely in horse production without the fear of impacting fundamental parameters of foal or placental development.