Testicular Size.

Testicular Size.
Scrotal circumference (SC) reflects testicular size. The size of the testes correlates directly with sperm output. In a ram lamb > 22 kg, the SC should be > 30 cm; in a yearling ram lamb, 12 to 18 months of age, > 33 cm; in a mature ram > 36 cm.

Smith MC (2006)