A case report: Documenting intrauterine single twin death in the European roe deer (Capreolus capreolus)

This case report presents a rare occurrence of an intrauterine single twin demise in a captive European roe deer ( Capreolus capreolus ), representing to the best of our knowledge the first documented instance of this phenomenon in a wildlife species. Ultrasound examination of the reproductive organs of a twin-pregnant doe revealed that one twin was smaller and showed an absent heartbeat compared to the other twin. The viable twin displayed normal development and birth, while the dead twin exhibited signs of intrauterine fetal death. This phenomenon of single twin demise in an ungulate species known for its ability to undergo embryonic diapause highlights the importance of understanding reproductive anomalies in wildlife. Such findings enhance our knowledge of reproductive biology and have implications for wildlife conservation and captive breeding practices.