Pubertal age based on testicular and epididymal histology in Göttingen minipigs.

Göttingen minipigs are used worldwide as nonrodent animal models for toxicologic and pharmaceutical research. Having knowledge of the age for onset of puberty is an important consideration when designing such biomedical experiments. The present study reports an earlier age for puberty on the basis of changes in testicular spermatogenic development in the Göttingen minipig. Testes and epididymides of 24 Göttingen minipigs ranging 5 to 8 weeks of age were obtained for histologic observation after hematoxylin-eosin staining. Microscopic examination was performed to determine the prevalence of cell types (e.g., spermatogonia, primary and secondary spermatocytes, round spermatids, elongated spermatids, luminal sperm) in seminiferous tubules and for the presence of sperm in the cauda epididymis. Puberty was defined as having a majority cell type presence of elongated spermatids in the seminiferous tubules in conjunction with the presence of spermatozoa in the cauda epididymis. Puberty was identified in two males at 6 weeks of age, two males at 7 weeks of age, and in all 6 males at 8 weeks of age. In conclusion, the age of puberty in male Göttingen minipigs occurs by 8 weeks of age, an earlier age than previously reported.