Estrous cycle
Estrous cycle, also known as emotional cycle, is a female placental mammals have a regular physiological changes, induced by the body's sex hormones. The length of time between the previous ovulation period and the next ovulation period is called a cycle. Animals, the concentration of various hormones and animal fertility are with the emotional cycle changes. The length of the animal's emotional cycle is different. Human emotional cycle phenomenon known as menstruation, the length is about 28 days. The estrous cycle begins in the mature adolescent females, which are temporarily stopped during the break or during pregnancy until the next cycle begins. This cycle will last until death. Some animals in the emotional cycle, the vagina will have bloody secretions, and these secretions are sometimes mistaken for menstruation. ...