Parity structure of healthy cattle

China black-and-white cow should be selected, and its appearance has the following characteristics: tall, symmetrical structure, large and plump breasts, extending forward and backward, moderate nipple size, obvious breast texture, large and deep milk well, strong limbs, good posture and distinct black-and-white flowers. Good production performance: under general feeding conditions, the lactation period of dairy cows is 270-305 days, the milk yield is about 4500 kg, and the average milk fat rate is 3.4%. At the same time, it has strong adaptability, long service life and stable genetic performance.