From the Treatment Codex:
"Most noticeably, small, rounded horns will typically grow in on the upper forehead. "Getting your horns" is a sign of adulthood on New Texas, but other bovine features may occur as well. Ears, cow tails, and furred thighs are all common. Some women may find their feet sculpted into hooves or hoof-like heels as well. Multiple nipples or breasts are somewhat rare, but do occur frequently enough for it to be a well-understood phenomenon. Cows with both are typically considered very desirable, both as milk producers and as mates."