Cowboy Dictionary - Letter U
Ungulate - A mammal with hooves. Horses are odd-toed ungulates and cattle are even-toed ungulates.
Below: A horse hoof. A horse has one solid (not split) hoof at the bottom of each leg. Since one is an odd number, a horse is an odd-toed ungulate.

Below: Calf hooves. Cattle have a hoof that is split into two toes at the bottom of each leg. Since two is an even number, cattle are even-toed ungulates.

CowboyWay Dictionary