Relationship between body measurements and serum testosterone levels of Dorper rams

In this study the serum testosterone levels of 177 Dorper rams participating in the Free State ram performance testing scheme were determined and correlated to certain phenotypic traits, body measurements and growth performance. All rams were managed extensively on natural pastures. Serum testosterone levels showed a positive correlation (P < 0.05) with masculinity (visual secondary masculinity traits). Rams with a wedge shape score of between 5 and 7 were significantly (P < 0.01) heavier than rams with wedge shape scores of between 2 and 4. The results emanating from this study suggest a significant relationship between serum testosterone level and scrotal circumference, but not with linear shape type score in Dorper rams.