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Anatomy and
Physiology of the Ram

Health
Seasonal effects
Sheep

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Anatomy and Physiology of the Ram

The ram’s testes weigh about 0.5% of the ram's bodyweight. They produce sperm and hang in the scrotum so they can be kept cool in hot weather. Sperm that heat up to body temperature are killed off and the ram is infertile.

Scrotal circumference for hoggets should be 28.5cm and adult rams 32cm.

Semen quality of the ram is generally very high, with sperm concentration of about 3 billion sperm per mL. More than 30% of these sperm should be progressively motile and >50% have normal morphology. Sperm production takes 6 weeks and any check in the ram’s health during this time (fever, malnutrition, lameness, time off feed, flystrike) will cause sperm death. The serving capacity of healthy rams is rarely a cause for under-performance.

Rams_Penis_Urethral_Process_Diagram

Diagram showing the shape of the normal ram penis with the urethral process (E.S.E Hafez, Reproduction in Farm Animals' 3rd edition, Lea & Febiger 1974)

Sperm_Mobility_Diagram

Recommendations

Provide shade for rams and access to fresh water to allow them to keep cool and maintain normal sperm production.

Rams should be left undisturbed for 6 weeks prior to the time of start of joining.

Joining in the hottest months of the year may affect ram fertility as well as embryo survival.

Undertake Ram inspection 12 weeks prior to joining

Further Reading

A Better Way To Buy