Serum and Testicular Testosterone Levels of Ram Lamb during Puberty

This study was done in order to investigate the levels of serum and testicular testosterone during puberty age in sheep. Twelve lambs aged at 3 months and two mature rams aged at 3 years were subject to this study. Serum testosterone was taken every two weeks for six months from all animals starting from November 2017 to April 2018. Castration was done to mature males at the end of this study. Castration for young lambs was done for twoof them every month. Serum and testicular testosterone were analyzed with commercial gamma counter kits. Results showed that there were a significant differences (P<0.05) between mature rams and lambs under 6 months age. The testicular testosterone showed significant differences (P<0.05) between mature rams and lambs under 5 months of age, with significant (P<0.01) correlation with hormonal level and ages. It could be concluded that the serum and the testicular testosterone could be used as an indicator for puberty age with more accuracy for testicular level in sheep.