Abstract
Extract
Sterilization may be defined as a process that renders a patient infertile without impairing sexual urge. The interest in sterilization of bulls has grown in recent years in New Zealand, for there is an increasing need for teasers for oestrus detection in both the dairy and beef herds. The advent of the mating harness (Lang et al., 1968) has increased the usefulness of such animals. Bulls may be sterilized by vasectomy, surgery on the cauda epididymis, injection or sclerotherapeutic agents into that organ, or by operations to shorten or deviate the penis. In this article vasectomy is compared with transection of the cauda epididymis.