The next time you're in the dairy aisle at the supermarket, take a moment to imagine the animals that produced all that milk. Do these cows have horns? Chances are they do, or at least they did at birth.
About 85 percent of milk sold in the United States comes from Holstein cows born with horns. But it's standard practice for farms to remove horns from cattle to prevent injuries to workers, veterinarians and other cows in the herd.