means that the best milk source comes from 45 degrees north latitude. This latitude can be described as a magical existence-it is parallel to the middle of the equator and the North Pole; Its annual sunshine averages more than 3 hours; It is the best place for the reproduction and growth for animals and plants. It includes oceans, plains, snowfields, grasslands, mountains and other landforms; It is known as the "golden milk source belt of the world". The natural golden pasture in this latitude area is rich in water plants and pollution-free. The pasture in this area has unique forage resources and is rich in crude protein, crude fat, calcium, phosphorus and other nutrients needed by dairy cows, providing them with the best nutrition, so that dairy cows can also produce the best milk source in the world.