Changes

* Both ovaries are enclosed within a fold of the [[Broad Ligament - Anatomy & Physiology#Structure|mesosalpinx]] known as the ovarian bursa, the apex of this bursa forms a large circular orifice within which lies the fimbriae of the oviduct.

* Both ovaries are enclosed within a fold of the [[Broad Ligament - Anatomy & Physiology#Structure|mesosalpinx]] known as the ovarian bursa, the apex of this bursa forms a large circular orifice within which lies the fimbriae of the oviduct.

* Their general appearance and size varies according to the age and activity of the animal.

* Their general appearance and size varies according to the age and activity of the animal.

** In the prepubertal animals they have a smooth and glistening surface with several raised small vesicles (2 - 5 mm in diameter) throughout the surface which correspond to the [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicles]].

** In the prepubertal animals they have a smooth and glistening surface with several raised small vesicles (2 - 5 mm in diameter) throughout the surface which correspond to the [[Follicles - Anatomy & Physiology|follicles]].

** In anoestrous females the [[Ovary - Anatomy & Physiology|ovaries]] are oval or circular, flattened laterally and have an irregular surface due to many small [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicles]].

** In anoestrous females the [[Ovary - Anatomy & Physiology|ovaries]] are oval or circular, flattened laterally and have an irregular surface due to many small [[Follicles - Anatomy & Physiology|follicles]].

** During the breeding season, mature [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicles]] and current [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|corpora lutea]] (CL) project from the main contour of the [[Ovary - Anatomy & Physiology|ovary]] and give it a more lobular form.

** During the breeding season, mature [[Follicles - Anatomy & Physiology|follicles]] and current [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|corpora lutea]] (CL) project from the main contour of the [[Ovary - Anatomy & Physiology|ovary]] and give it a more lobular form.

*** This lobulation increases with increased number of previous [[The_Ovary_-_Ovulation_- Anatomy & Physiology|ovulations]] or pregnancies and is due mainly to the presence of old [[The_Ovary_-Corpus_Albicans_- Anatomy & Physiology|corpora albicantia]].

*** This lobulation increases with increased number of previous [[The_Ovary_-_Ovulation_- Anatomy & Physiology|ovulations]] or pregnancies and is due mainly to the presence of old [[The_Ovary_-Corpus_Albicans_- Anatomy & Physiology|corpora albicantia]].

==== Follicles ====

==== Follicles ====

* Follicular activity is dominated by 4 types of [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicles]]

* Follicular activity is dominated by 4 types of [[Follicles - Anatomy & Physiology|follicles]]

** Small growing follicles

** Small growing follicles

** Mature follicles

** Mature follicles

** Regressing follicles

** Regressing follicles

** Over-large, anovulatory follicles

** Over-large, anovulatory follicles

* As the [[The_Ovary_-_Folliculogenesis_- Anatomy & Physiology|follicular waves]] overlap with each other, several generations of [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicles]] may be present at the same time.

* As the [[The_Ovary_-_Folliculogenesis_- Anatomy & Physiology|follicular waves]] overlap with each other, several generations of [[Follicles - Anatomy & Physiology|follicles]] may be present at the same time.

* The small growing follicles are visible on the surface of the [[Ovary - Anatomy & Physiology|ovary]] as small slightly raised vesicles measuring between 2 - 4 mm, whereas the mature pre-ovulatory follicle measures between 13 - 20 mm [19,20] and is spherical, turgid, with a thin clear translucent wall and protrudes markedly from the [[Ovary - Anatomy & Physiology|ovarian surface]].

* The small growing follicles are visible on the surface of the [[Ovary - Anatomy & Physiology|ovary]] as small slightly raised vesicles measuring between 2 - 4 mm, whereas the mature pre-ovulatory follicle measures between 13 - 20 mm [19,20] and is spherical, turgid, with a thin clear translucent wall and protrudes markedly from the [[Ovary - Anatomy & Physiology|ovarian surface]].

* The appearance of regressing follicles depends on the stage of regression.

* The appearance of regressing follicles depends on the stage of regression.

* Forms after [[The_Ovary_-_Ovulation_- Anatomy & Physiology|ovulation]], which occurs 24 - 48 hours after mating.

* Forms after [[The_Ovary_-_Ovulation_- Anatomy & Physiology|ovulation]], which occurs 24 - 48 hours after mating.

* The ovulating [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicle]] collapses at [[The_Ovary_-_Ovulation_- Anatomy & Physiology|ovulation]] and then the follicular cavity fills with blood to form a [[Corpus Haemorrhagicum - Anatomy & Physiology|corpus haemorrhagicum]].  

* The ovulating [[Follicles - Anatomy & Physiology|follicle]] collapses at [[The_Ovary_-_Ovulation_- Anatomy & Physiology|ovulation]] and then the follicular cavity fills with blood to form a [[Corpus Haemorrhagicum - Anatomy & Physiology|corpus haemorrhagicum]].  

* [[Corpus_Luteum_Formation_-_Anatomy & Physiology|Luteinization]] of the [[Corpus Haemorrhagicum - Anatomy & Physiology|corpus haemorrhagicum]] occurs within 4 - 5 days and gives rise to a [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|corpus luteum]].  

* [[Corpus_Luteum_Formation_-_Anatomy & Physiology|Luteinization]] of the [[Corpus Haemorrhagicum - Anatomy & Physiology|corpus haemorrhagicum]] occurs within 4 - 5 days and gives rise to a [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|corpus luteum]].  

* [[Corpus_Luteum_Regression -_Anatomy_&_Physiology|Regression]] of the [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|CL]] occurs between 10 - 12 days after a sterile mating or just before parturition in the pregnant female.

* [[Corpus_Luteum_Regression -_Anatomy_&_Physiology|Regression]] of the [[The_Ovary_-Corpus_Luteum_- Anatomy & Physiology|CL]] occurs between 10 - 12 days after a sterile mating or just before parturition in the pregnant female.

* The [[Cervix - Anatomy & Physiology|cervix]] protrudes caudally in the vaginal cavity forming a fornix.

* The [[Cervix - Anatomy & Physiology|cervix]] protrudes caudally in the vaginal cavity forming a fornix.

* The size of the protruded vaginal portion of the [[Cervix - Anatomy & Physiology|cervix]] and the actual position within the vaginal cavity varies between individuals and the appearance of the external cervical os varies according to the stage of the cycle.

* The size of the protruded vaginal portion of the [[Cervix - Anatomy & Physiology|cervix]] and the actual position within the vaginal cavity varies between individuals and the appearance of the external cervical os varies according to the stage of the cycle.

** In the presence of a mature [[The_Ovary_-_Follicles_- Anatomy & Physiology|follicle]] the [[Cervix - Anatomy & Physiology|cervix]] is contracted and oedematous and appears open on vaginal examination.

** In the presence of a mature [[Follicles - Anatomy & Physiology|follicle]] the [[Cervix - Anatomy & Physiology|cervix]] is contracted and oedematous and appears open on vaginal examination.

** During the luteal phase, it becomes dry and the cervical os is usually covered by a flap of the last two cervical rings.

** During the luteal phase, it becomes dry and the cervical os is usually covered by a flap of the last two cervical rings.

** During pregnancy the [[Cervix - Anatomy & Physiology|cervix]] becomes very tight and in the advanced stages the cervix is pulled forward and downward beyond the pelvic brim.

** During pregnancy the [[Cervix - Anatomy & Physiology|cervix]] becomes very tight and in the advanced stages the cervix is pulled forward and downward beyond the pelvic brim.