Related Experiment Video
Updated: Aug 6, 2025
08:55
Mouse Embryonic Development in a Serum-free Whole Embryo Culture System
Published on: March 1, 2014
26.1K
Delayed embryonic development or a long sperm survival in two mares-A registration conundrum
Patrick M McCue1, Philip M Matthews2, Melissa J Prell2
1Equine Reproduction Laboratory, Colorado State University, Fort Collins, Colorado, USA.
Equine Veterinary Journal
|March 14, 2023
Summary
Delayed fertilization or embryonic development in horses can lead to incorrect parentage. Genetic testing is crucial for accurate foal registration, overriding traditional breeding records in rare cases.
Area of Science:
- Equine reproduction
- Animal genetics
- Veterinary science
Background:
- Genetic testing is standard for foal registration in most equine breeds.
- Accurate parentage verification is essential for breed registries and genetic management.
Observation:
- Two clinical cases involving equine embryo transfer presented with delayed embryonic development or fertilization.
- Donor mares were inseminated with semen from different stallions in consecutive cycles.
Findings:
- DNA parentage testing revealed that the sire of the foals was from the earlier insemination cycle, not the later one.
- This indicated a significant delay in fertilization or embryonic development, or extended sperm viability.
Implications:
- The study highlights the importance of genetic testing for definitive parentage assignment in horses.
- Breeding records alone can be misleading due to rare reproductive phenomena like delayed fertilization.
- These findings have implications for equine breeding programs and genetic management strategies.
