Shape
The normal or ‘football shaped’ scrotum in bull indicates optimum testicular development and function. A straight sided scrotum ie. Lacks the neck, is usually a result of fat deposits. This may impair thermoregulation of the testes, hence depending normal sperm production.
The length of the testicles should be equal for optimal sperm production and quality. This is reflected in research showing that bulls with equal testicles measures have higher conception rate.