Repetitive testicular biopsy in the ram during pubertal development.

A procedure for testicular biopsy was developed and tested in rams at 14, 18 and 22 wk of age. The biopsy procedure produced a tissue sample with minimal cell-to-cell disruption and caused no detectable detriment to testicular development in rams. At least three biopsies from the same testis were obtained at 4-wk intervals without influencing the developmental patterns of either the biopsied or nonbiopsied testicle. Data obtained by biopsy indicated that the testes of Suffolk rams reached a comparable stage of development (22 wk of age) approximately 4 wk later than the testes of Finnsheep rams (18 wk of age). These results demonstrate that repetitive testicular biopsy can be performed successfully in the ram during pubertal development. The biopsy procedure allows repeated sampling of the same animal and offers a reasonable alternative to castration.