Fig. 1

Histological evaluation. a Representative picture of the right testis, taken from the middle section. Two tubules are shown, the left one presenting only primary spermatocytes (lined arrowheads) and degenerating germ cells (asterisk), whereas the right tubule shows additionally a small group of elongated spermatids (circle). Gray lined arrowheads: spermatogonia. b Representative picture of the left testis, taken from the lower pole. Two tubules are shown, the left one presenting single primary spermatocytes (lined arrowheads) and spermatogonia (gray lined arrowheads) correctly aligned to the basal membrane, and the right tubule showing high numbers of spermatogonia/spermatogonia-like cells, dislocated and no longer restricted to the basal membrane (black arrowheads) with a single spermatocyte. Hematoxylin eosin (HE) staining, bar 50 μm