oestrous cycle in detail including: proestus phase, estrous phase, metestrus phase, anoestrus phase

The oestrous cycle is the reproductive cycle in female mammals, including humans. It consists of four main phases: proestrus, estrus, metestrus, and anestrus. – Proestrus phase: This is the phase of the cycle where the female prepares for mating. Hormones such as estrogen are released, causing physical and behavioral changes. For example, in dogs, proestrus is characterized by vaginal bleeding and swelling of the vulva. – Estrus phase: This is the phase where the female is most fertile and receptive to mating. Hormone levels peak during this phase, leading to ovulation. For example, in cows, estrus is known as “heat” and is when they show signs of sexual receptivity. – Metestrus phase: This is the phase following estrus, where the female may still be fertile but is less receptive to mating. Hormone levels start to decrease, and the uterus prepares for potential pregnancy. For example, in cats, metestrus is a time when they may still exhibit some mating behaviors but are less likely to mate. – Anestrus phase: This is the phase of the cycle where the female is not fertile and does not show signs of being in heat. Hormone levels are low during this phase, and the reproductive system is inactive. For example, in bears, anestrus occurs during the winter months when they go into hibernation. One verifiable fact is that the length and timing of the oestrous cycle can vary greatly between different species of mammals. For example, the oestrous cycle in mice is only 4-5 days, while in elephants, it can last up to 4 months.