Article

Effects of intravenous multiple busulfan injection on suppression of endogenous spermatogenesis in recipient stallion testes

Minjung Yoon*, Heejun Jung
Author Information & Copyright
1Department of Horse, Companion, and Wild Animal Science, Kyungpook National University , Sangju 37224, Korea.
2Kyungpook National University , Sangju 37224, Korea.
*Corresponding Author: Minjung Yoon, E-mail: mjyoonemail@gmail.com.

© Copyright 2021 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 (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: May 07, 2021; Revised: Jun 01, 2021; Accepted: Jun 01, 2021

Published Online: Jul 26, 2021

Abstract

Preparation of recipient stallions is critical step to produce donor spermatogonial stem cell derived sperm using transplantation technique. This study was conducted to evaluate the effects of intravenous busulfan infusion on germ cell depletion, semen production, and libido in stallions. Six Thoroughbred stallions were separated into two treatment groups: 1) a multiple low-dose (2.5 mg/kg bw for the first 4 weeks and 5 mg/kg bw for the 5<sup>th</sup> week); and 2) control group treated with PBS. Testicular samples were obtained at 11 weeks and classified into three different patterns of spermatogenesis, such as normal, Sertoli cell only, and destroyed. Semen collection and libido experiments were performed 1 week before treatment, and 4 and 8 weeks after treatment. For the sperm analysis, total spermatozoa and motility were measured using a light microscope with a motility analyzing system. In the multiple low-dose group, the numbers of tubules categorized as Sertoli cell only were significantly higher than those in the control as well as the total population and total/progressive motility of sperm were significantly decreased 8 weeks after the start of the treatment. The sperm production and motility in the multiple low-dose group appears to be reduced, while libido was maintained. In conclusion, multiple administration of 2.5 mg/kg bw busulfan depletes endogenous germ cells in the stallion recipients for SSC transplantation.

Keywords: Busulfan; Germ cell depletion; Sperm; Stallion