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Avian Male Reproductive Tract - Anatomy & Physiology (view source)
Revision as of 10:27, 22 July 2008
, 10:27, 22 July 2008→Testes
* Dormant testes light brown/yellow in colour, turn white when sexually active.
* Dormant testes light brown/yellow in colour, turn white when sexually active.
** In some psittacine species, immature or dormant testes may appear black due to melanocytes located in the interstitium.
** In some psittacine species, immature or dormant testes may appear black due to melanocytes located in the interstitium.
* Tunical Albiguinea thinner than in mammals.
* '''No Pampiniform plexus'''.
* Convoluted semniferous tubules comprised of spermatogonia (germ cells) and Sertoli cells make up the bulk of the testes. These are responsible for spermatogenesis.
* Convoluted '''semniferous tubules''' comprised of '''spermatogonia''' (germ cells) and '''Sertoli cells''' make up the bulk of the testes. These are responsible for '''spermatogenesis'''.
* Interstitial Leydig cells produce male androgens.
* '''Interstitial Leydig cells''' produce male androgens.
* Mature spermatozoa exit into the rete testes, which connects to the cranial epididymis.
* Mature spermatozoa exit into the '''rete testes''', which connects to the cranial '''epididymis'''.
** Rete testes not present in all birds.
** Rete testes not present in all birds.
** Epididymis considered vestigial in birds.
** Epididymis considered vestigial in birds.
*** Sperm maturation occurs in the ductus deferens.
*** Sperm maturation occurs in the '''ductus deferens'''.
* Epididymis lies along the dorsomedial aspect of the testes.
* Epididymis lies along the dorsomedial aspect of the testes.
* Spermatazoa exit the epididymis and enter the ductus deferens.
* Spermatazoa exit the epididymis and enter the ductus deferens.
** Ductus deferens is closely associated with the Ureter in the dorsomedial midline coelom, distinguished by its zig-zag appearance.
** Ductus deferens is closely associated with the Ureter in the dorsomedial midline coelom, distinguished by its zig-zag appearance.
** Under hormonal control, more convoluted in the breeding season.
** Under hormonal control, more convoluted in the breeding season.
* Ductus deferens enters the dorsal wall of the cloacal urodeum.
* Ductus deferens enters the dorsal wall of the '''cloacal urodeum'''.
** Straightens and abruptly widens at ats junction with the cloaca.
** Straightens and abruptly widens at ats junction with the cloaca.
*** Structure known as the receptacle.
*** Structure known as the '''receptacle''' in Passerines and Budgerigars.
*** Receptacle appears bean-shaped when engorged with semen.
*** Receptacle appears bean-shaped when engorged with semen.
*** Birds that do not have the receptacle structure have little sperm storage capacity.
* Tunical Albiguinea thinner than in mammals.
* '''No Pampiniform plexus'''.
* '''Epididymis is small and can be considered absent'''. '''.
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