Duration of Spermatogenesis in the Mouse

Abstract

WE wish to comment on Dr. Oakberg's criticism of our communication¹. We stated there that the transcription of frequency of tubule stages from rat to mouse could provide only “approximate intervals”. However, when our communication was written, Oakberg's paper on the timing of spermatogenic stages in the mouse² was not available to us, and we had to extrapolate from the rat³ on the assumption that spermatogenesis in these species was similar : this we clearly stated¹. We realized, therefore, that only “reasonable agreement” could be expected between the cytological and tracer results as we presented them, and that work similar to that of Ortavant in the ram⁴ gives a clearer indication of the duration of spermatogenesis⁵. Furthermore, Oakberg has obviously overlooked the assumption, based on the work of Swift⁶, that we made in our calculations on the tracer results¹, namely, that preleptotene spermatocytes were initially labelled by adenine.