Estrous cycle: Difference between revisions
CSV import Tags: mobile edit mobile web edit |
CSV import |
||
| Line 1: | Line 1: | ||
{{Short description|Overview of the estrous cycle in mammals}} | |||
{{Use dmy dates|date=October 2023}} | |||
== Overview == | ==Overview== | ||
The '''estrous cycle''' is a recurring physiological process that occurs in most [[female]] [[mammals]], including many [[domesticated animals]]. It is the period during which a female is sexually receptive and capable of conceiving. The cycle is characterized by a series of hormonal changes that prepare the body for [[ovulation]] and potential [[pregnancy]]. | |||
[[File:Estrous_cycle.png|thumb|right|Diagram of the estrous cycle stages.]] | |||
== | ==Phases of the Estrous Cycle== | ||
The estrous cycle is divided into several distinct phases: | |||
The | ===Proestrus=== | ||
During the '''proestrus''' phase, the body prepares for ovulation. This phase is marked by the growth of [[follicles]] in the [[ovaries]] and an increase in [[estrogen]] levels. The [[endometrium]] begins to thicken in preparation for a potential pregnancy. | |||
===Estrus=== | |||
The '''estrus''' phase, also known as "heat," is when the female is sexually receptive. Ovulation occurs during this phase, and estrogen levels peak. This is the optimal time for [[fertilization]] to occur. | |||
===Metestrus=== | |||
Following estrus, the '''metestrus''' phase begins. During this time, the [[corpus luteum]] forms from the remnants of the follicle and begins to secrete [[progesterone]]. This hormone helps maintain the endometrium and supports early pregnancy if fertilization has occurred. | |||
===Diestrus=== | |||
The '''diestrus''' phase is characterized by high levels of progesterone. If pregnancy does not occur, the corpus luteum degenerates, leading to a decrease in progesterone levels and the eventual return to proestrus. | |||
===Anestrus=== | |||
Some species experience an '''anestrus''' phase, a period of reproductive inactivity between cycles. This phase can vary in length depending on the species and environmental factors. | |||
== Hormonal Regulation == | ==Hormonal Regulation== | ||
The estrous cycle is regulated by a complex interplay of hormones, primarily [[gonadotropin-releasing hormone]] (GnRH), [[luteinizing hormone]] (LH), [[follicle-stimulating hormone]] (FSH), estrogen, and progesterone. These hormones are produced by the [[hypothalamus]], [[pituitary gland]], and ovaries. | |||
==Species Variations== | |||
Different species exhibit variations in the length and characteristics of their estrous cycles. For example, [[dogs]] have a cycle that lasts approximately six months, while [[cows]] have a cycle of about 21 days. Understanding these differences is crucial for [[veterinary medicine]] and [[animal husbandry]]. | |||
==Related pages== | |||
* [[Menstrual cycle]] | * [[Menstrual cycle]] | ||
* [[Reproductive system]] | |||
* [[Ovulation]] | * [[Ovulation]] | ||
* [[ | * [[Hormonal contraception]] | ||
[[Category:Reproductive system]] | [[Category:Reproductive system]] | ||
[[Category: | [[Category:Animal physiology]] | ||
Latest revision as of 10:58, 15 February 2025
Overview of the estrous cycle in mammals
Overview[edit]
The estrous cycle is a recurring physiological process that occurs in most female mammals, including many domesticated animals. It is the period during which a female is sexually receptive and capable of conceiving. The cycle is characterized by a series of hormonal changes that prepare the body for ovulation and potential pregnancy.
Phases of the Estrous Cycle[edit]
The estrous cycle is divided into several distinct phases:
Proestrus[edit]
During the proestrus phase, the body prepares for ovulation. This phase is marked by the growth of follicles in the ovaries and an increase in estrogen levels. The endometrium begins to thicken in preparation for a potential pregnancy.
Estrus[edit]
The estrus phase, also known as "heat," is when the female is sexually receptive. Ovulation occurs during this phase, and estrogen levels peak. This is the optimal time for fertilization to occur.
Metestrus[edit]
Following estrus, the metestrus phase begins. During this time, the corpus luteum forms from the remnants of the follicle and begins to secrete progesterone. This hormone helps maintain the endometrium and supports early pregnancy if fertilization has occurred.
Diestrus[edit]
The diestrus phase is characterized by high levels of progesterone. If pregnancy does not occur, the corpus luteum degenerates, leading to a decrease in progesterone levels and the eventual return to proestrus.
Anestrus[edit]
Some species experience an anestrus phase, a period of reproductive inactivity between cycles. This phase can vary in length depending on the species and environmental factors.
Hormonal Regulation[edit]
The estrous cycle is regulated by a complex interplay of hormones, primarily gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen, and progesterone. These hormones are produced by the hypothalamus, pituitary gland, and ovaries.
Species Variations[edit]
Different species exhibit variations in the length and characteristics of their estrous cycles. For example, dogs have a cycle that lasts approximately six months, while cows have a cycle of about 21 days. Understanding these differences is crucial for veterinary medicine and animal husbandry.
