They were first bred in the Netherlands and brought to America in 1857. These cattle are instantly recognizable by their black and white coat color; they are, so to speak, the prototype of domestic cattle. Today, black and white cattle are kept for their remarkable milk production: the average cow produces 12,000 liters of milk per year. They live for three to four years, but some have a significantly longer lifespan. Cattle have four stomachs. In barn housing, they eat a combination of grasses and hay, which is then regurgitated. The partially digested food is pushed back from the first stomach into the mouth, where it is chewed until it reaches a state that allows it to pass through the other three stomachs. The cows then look as if they are chewing gum.