Diagram 1. The testicle of a ram (right hand side when viewed from behind).

Epididymis

The epididymis absorbs testicular fluid and concentrates the spermatozoa into a tightly packed mass enabling large quantities of sperm to be stored in the smallest possible space. Healthy, well-fed and sexually rested rams may hold up to 100,000 million sperm, of which about 75 per cent will be stored in the tail of the epididymis.

Palpation of the tail of the epididymis is often a useful guide to the level of sperm reserves in individual rams. A large, firm (but not hard and diseased) tail is an indication of good reserves whereas a small, soft tail would indicate the opposite.

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