A baby cow is called a calf. Adult male cows are called bulls. Adult female cows are called heifers until they give birth; after they have given birth, they are called cows.
Both male and female cows are born with horns. Calves are usually 75 to 95 pounds at birth. They are weaned from their mother when they are between 7 and 9 months old, when they weigh between 400 and 600 pounds.
Cows are herd animals that were domesticated by humans as far back as 5,000 years ago. The first cow in the United States was brought to Jamestown, VA in 1611, and over 70 breeds of cattle can be found in the U.S. today.