Changes

* In females, '''FSH''' is mainly responsible for follicular growth.

* In females, '''FSH''' is mainly responsible for follicular growth.

* Developing follicles produce '''Oestrogen''' from '''Theca and interstitial cells''' and '''Progesterone''' from '''Granulosa cells'''.

* Developing follicles produce '''Oestrogen''' from '''Theca and interstitial cells''' and '''Progesterone''' from '''Granulosa cells'''.

* Increasing levels of Oestrogen stimulate an '''LH surge''' to cause the [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicle]]  to split and release the primary [[The_Ovary_-_Oocytes_- Anatomy & Physiology|oocyte]].

* Increasing levels of Oestrogen stimulate an '''LH surge''' to cause the [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicle]]  to split and release the primary [[Oogenesis - Anatomy & Physiology|oocyte]].

* '''Oestrogen mobilizes calcium''' from the bone, increasing plasma concentrations for [[Egg Composition and Formation - Anatomy & Physiology|egg formation]].

* '''Oestrogen mobilizes calcium''' from the bone, increasing plasma concentrations for [[Egg Composition and Formation - Anatomy & Physiology|egg formation]].

* '''Progesterone''' secretion continues to inhibit further ovulation and stimulate behavioural changes associated with '''broodiness and incubation'''.

* '''Progesterone''' secretion continues to inhibit further ovulation and stimulate behavioural changes associated with '''broodiness and incubation'''.

== Ovulation==

== Ovulation==

* Number of ovulations varies with species, mostly lay one clutch a year.

* Number of ovulations varies with species, mostly lay one clutch a year.

* [[Avian Female Reproductive System#Infundibulum|Infundibulum]] catches the [[The_Ovary_-_Oocytes_- Anatomy & Physiology|oocyte]], facillitated by the left abdominal air sac which tightly encloses the [[Avian Female Reproductive System#Ovary|ovary]].

* [[Avian Female Reproductive System#Infundibulum|Infundibulum]] catches the [[Oogenesis - Anatomy & Physiology|oocyte]], facillitated by the left abdominal air sac which tightly encloses the [[Avian Female Reproductive System#Ovary|ovary]].

* Once ovulation has taken place, the  [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicle]] shrinks and regresses.

* Once ovulation has taken place, the  [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicle]] shrinks and regresses.

* '''No [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|corpus luteum]]''' remains, as there is no developing embryo to maintain.

* '''No [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|corpus luteum]]''' remains, as there is no developing embryo to maintain.