ovulation cycle estrous cycle http://purl.bioontology.org/ontology/MESH/D030762 https://en.wikipedia.org/wiki/Estrous_cycle A type of ovulation cycle, which occurs in most mammalian therian females, where the endometrium is resorbed if pregnancy does not occur. The period of cyclic physiological and behavior changes in non-primate female mammals that exhibit estrus. The estrous cycle generally consists of 4 or 5 distinct periods corresponding to the endocrine status (proestrus; estrus; metestrus; diestrus; and anestrus). estrous cycles estrous cycle phase