By assigning a simple, 15-digit identification number to cows, UC researchers can track each one from conception to carcass, garnering valuable data for studies on cattle fertility, genetics, and health, and helping to select breeding animals with desirable beef characteristics such as flavor and tenderness.

In today’s beef market, an individual cow may change ownership many times during its lifetime as it travels from the ranch of its birth, to stocker and feedlot, to slaughterhouse, and finally supermarket or steakhouse. In the process, valuable data is lost along with the ability to “trace back” particular steaks to the original cow.

For several years, UC Davis researchers have been attaching a round, electronic ear...