How often are bulls sterile?

Infertility rates in bulls are estimated to be between 15 to 25 percent in the United States and Canada. In most cases, bulls that have been in the herd for a year or more are assumed to be of sound breeding value, however, this is not necessarily true.

How can I make my bull more fertile?

Zinc supplementation has been shown to increase ejaculate volume, sperm concentration and motility in bulls. Furthermore, chelated/organic sources of zinc supplementation resulted in more improved fertility than did inorganic sources alone (Arthington et al., 2002).