STEM CELL-BASED TECHNOLOGIES OF ASSISTED REPRODUCTION IN THE CAT AND DOG

Spermatogonial stem cells (SSC) exist on the basement membrane of the seminiferous tubules in the testis throughout a male animalʼs life. These cells self-renew to maintain a stem cell population while producing daughter cells that differentiate into sperm. Because of their relatively undistinguishable morphology, very little was known about them until testis xenografting and spermatogonial stem cell transplantation (SSCT) were developed. Both technologies are promising tools to preserve male genetic information as well as to study the characteristics of SSC. In this dissertation, I investigate testis xenografting and SSCT in cats and dogs, which are important animal models for biomedical research. First, I examine the effect of donor age on spermatogenesis in feline xenografts and the ability of xenograft-derived sperm to support embryo development. In addition, I compare the outcomes of xenografting using testis tissue from two additional species of carnivore, dogs and ferrets. My studies indicate that the optimal donor age was just prior to onset of puberty an