What period precedes the estrus phase in the estrous cycle?

The period that precedes the estrus phase in the estrous cycle is proestrus. During proestrus, the female's body undergoes significant hormonal changes that prepare it for mating. This phase is characterized by the development of ovarian follicles, increased estrogen production, and physical signs that indicate readiness for mating, such as swelling of the vulva and behavioral changes like increased restlessness or vocalization.

Understanding the estrous cycle is vital for those working with laboratory animals, as it influences breeding programs and animal behavior management. The proestrus phase establishes the necessary conditions that lead into estrus, the phase where the female is fertile and receptive to mating. This foundational knowledge is crucial for effective breeding management and the overall well-being of breeding animals in a laboratory setting.