Spermatogonial stem cell transfer to a mule

Abstract

Spermatogonial stem cell transfer has been studied in various species and suggested potential for success. Bull, stallion, donkey, mule, boar, dog and cat testicles were examined using various injection techniques to determine distribution patterns of injected material most favorable for stem cell transfer. Spermatogonial stem cells were recovered from freshly harvested stallion testicles using enzymatic digestion and filtration and placed in suspension for transplantation. An 18 mo old sexually intact male mule was anesthetized and the stem cell suspension was injected into both testicles in the area below the head of the epididymis. Semen collected from the mule four months post-transplantation contained no spermatozoa. The stem cell transfer was unsuccessful in this case, however further research is needed to determine recipient age of injection to optimize donor cell development.