Journal of Animal Science and Technology
Korean Society of Animal Science and Technology

Reproductive ability of minipigs as surrogates for somatic cell nuclear transfer

Joonho Moon, Su-Jin Kim, Jinseok Lee, Hyeyoung Kang, Bumrae Cho*, Sung Joo Kim**
1GenNBio Co., Ltd., Pyeongtaek-si 17796, Korea.
*Corresponding Author: Bumrae Cho, E-mail:
**Corresponding Author: Sung Joo Kim, E-mail:

© Copyright 2023 Korean Society of Animal Science and Technology. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Feb 13, 2023; Revised: Mar 23, 2023; Accepted: Apr 05, 2023

Published Online: Apr 11, 2023


Pigs are genetically, anatomically, and physiologically similar to humans. Recently, pigs are in the spotlight as a suitable source animal for xenotransplantation. However, to use pigs as source animals, pigs should be raised in designated pathogen-free facilities. There is abundant data from embryo transfer (ET) experiments using farm pigs as surrogates, but data on ET experiments using minipigs are scarce. Eighty minipigs were used for ET experiments and after transplantation, the implantation and delivery rates were investigated. It was also confirmed whether the pregnancy rate could be increased by changing the condition or surgical method of the surrogate. In the case of minipigs that gave birth, the size of the fetal sac on the 28th day of ET was also measured. The factors that can affect the pregnancy rate such as estrus synchronization program, ovulation status at the time of ET, the number of repeated ET surgeries, and the ET sites, were changed, and the differences on the pregnancy rate were observed. However there were no significant differences in pregnancy rate in minipigs. The diameter of the implanted fetal sac on the 28th day after ET in the minipigs whose delivery was confirmed was calculated to be 4.7 ± 1.5 cm. In conclusion, there were no significant differences in pregnancy rate of minipigs in the comparative experiment on various factors affecting the pregnancy rate. However, additional experiments and analyses are needed due to the large individual differences of the minipigs.

Keywords: embryo transfer; fetal sac diameter; minipig; pregnancy