by the Leibniz Institute for Zoo and Wildlife Research (IZW) of the Research Association Berlin eV
In the four years since starting an ambitious project to save the northern white rhino from extinction, the BioRescue consortium has made significant progress toward its ultimate goal. Using advanced assisted reproduction technologies, 29 northern white rhino embryos were created and cryopreserved, ready for future transfer to a surrogate mother.
During a scientific field trip to Kenya in May 2023, the thirteenth egg collection from the northern white rhinoceros (NWR) was made by a group of scientists and conservationists from the Leibniz Institute for Zoo and Wildlife Research (Leibniz -IZW), Ol Pejeta Conservancy, Safari Park Dvůr Králové, Kenya Wildlife Service (KWS) and Wildlife Research and Training Institute (WRTI) of Ol Pejeta Conservancy in Kenya.
The procedure involving the female rhino Fatu went smoothly without complications, and 18 eggs were harvested. They were matured and fertilized at the Avantea lab in Cremona, Italy, leading to five additional embryos being produced, the highest number of embryos from any egg collection to date. The sperm for fertilization comes from two different bulls, thus improving genetic diversity.
Previous procedures in November 2022 (eleventh collection) and February 2023 (twelfth collection) yielded two and zero embryos, respectively.
In addition, in May 2023 the BioRescue team took another promising step towards saving the most endangered mammal species on our planet. Consortium members successfully identified and selected two wild southern white rhino females (SWR) as potential surrogate mothers. Both women were checked and moved to a secure enclosure. They are now essential in supporting breeding efforts within the BioRescue project for NWRs.
Consortium members also checked the health status of SWR teaser bull Ouwan and confirmed that he is still sterilized. The teaser bull indicates by mating with a female that a potential SWR surrogate mother is ready to receive an embryo. The bull must be sterilized; otherwise, it would not make sense to do an embryo transfer, because the woman would be pregnant with the bull’s seed.
The next steps in the BioRescue project are to perform embryo transfers using SWR embryos to demonstrate that the chosen transfer protocol is suitable and works. If a confirmed pregnancy is achieved the team will use the protocol for transferring cryopreserved NWR embryos to produce live offspring as soon as possible.
Given by the Leibniz Institute for Zoo and Wildlife Research (IZW) of the Research Association Berlin eV
Citation: Five new embryos and new surrogate mothers added to northern white rhino rescue project (2023, July 17) retrieved on July 17, 2023 from https://phys.org/news/2023- 07-embryos-surrogate-mothers-added-northern. html
This document is subject to copyright. Except for any fair dealing for the purpose of private study or research, no part may be reproduced without written permission. Content is provided for informational purposes only.