Grabbing the Horns From the Bull

Big and boisterous, Spotigy and Buri appear to be standard 1-year-old bulls. But a quick glance at their furry heads and closer examination of their genes would reveal that they're unique specimens—hornless Holsteins. The bulls are the result of a gene-editing experiment by Alison Van Eenennaam and colleagues at UC Davis, along with researchers at the biotech company Recombinetics, who aim to develop hornless cattle that might one day replace cows whose horns must be physical removed through expensive and painful methods. Van Eenennaam explains how the technique of "precision breeding" can be a faster and more effective means of de-horning cows compared to traditional breeding methods.