Is Menstruation cycle is occur in animals?

Dear student, since your question is not clear, I am assuming it as why does menstrual cycle occur?Adolescents become capable of reproduction when their testes and ovaries begin to produce gametes. The capacity of maturation and production of gametes lasts for a much longer time in males than in females. In Females,the ova begin to mature with the onset of puberty. One ovum matures and is released by one of the ovaries once in about 28-30 days. During this period, the wall of uterus becomes thick so as to receive the egg. In case it is fertilized and begins to develop, known as pregnancy. If fertilization does not occur the released egg and the thickened lining of uterus along with its blood vessels are shed off. This causes bleeding in women, which is called menstruation or menstrual cycle. Thanks and regards