Non-surgical sterilisation of rams using a sclerosing agent.

Injection of 0.25 ml of a solution of 3.6% formaldehyde in 90% ethanol direct into the caudae epididymides caused sterility in the rams treated. No live sperm were seen in ejaculates collected 35, 57, 91 and 196 days post-injection. The rams retained their libido and were mated to ewes between 2 and 3 months post-injection with no pregnancy ensuing. The technique offers a simple, safe, quick and effective method of sterilising rams. Attempts to produce sterilisation by injection of the sclerosing agent into the vas deferens were not successful.