The long-term goal for this research was to produce a molecular expression profile of spermatogonial stem cells during postnatal stages of development in the ram. This stage of germline development is essential for fertility as many important cellular associations and molecular signaling events occur that in effect, set-up spermatogenesis for the remainder of an individual's reproductive years. Unfortunately, postnatal stages of development have been poorly studied. This thesis describes a methodology that employs the use of Laser Capture Microdissection for the successful isolation and quantification of gene expression in individual spermatogonia from postnatal ram testicular tissue through the use of quantitative real time PCR.