Milk comes from mammals, but the milk we buy in stores comes mostly from cows (sometimes you can buy goat's milk). A cow must give birth to a calf every year in order to produce milk. That's why you'll often find bulls associating with the heifers on dairy farms. A heifer is a young female that has had 0 or 1 calf. Once a heifer has 2 calves, she is called a cow. A cow produces about 1200 gallons of milk every year. How many gallons of milk does your family go through in a year? Enough to keep up with 1 cow? A cow must eat 3% of her body weight every day to make enough milk. That's about 154 pounds of food. Now you know what the phrase, "You eat like a cow!" means. She feeds on fresh grass, dried grass (hay), or pickled grass (silage), and from that grass you get the milk that strengthens your teeth, bones, and helps you to build muscle and grow strong!
Milk provides us with many of the dairy products you'll find in a local grocery store: whole milk, lowfat milk, buttermilk, kefir, yogurt, whipping cream, half-and-half, sour cream, butter, cheese, cottage cheese, powdered milk, evaporated milk, sweetened condensed milk, and ice cream. Look for these milk products the next time you shop.