Difference between revisions of "Chinchilla Reproduction - Anatomy & Physiology"

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=== Reproductive Tract ===
 
=== Reproductive Tract ===
  
* [[Ovary - Anatomy & Physiology|Ovaries]] are just caudolateral to the [[Macroscopic Renal Anatomy - Anatomy & Physiology#Common Anatomy|kidneys]].
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* [[Ovary - Anatomy & Physiology|Ovaries]] are just caudolateral to the [[Renal Anatomy - Anatomy & Physiology#Common Anatomy|kidneys]].
 
* [[Uterus - Anatomy & Physiology#Anatomical_Types_of_Uteri|Bicornuate duplex uterus]].
 
* [[Uterus - Anatomy & Physiology#Anatomical_Types_of_Uteri|Bicornuate duplex uterus]].
 
* [[Uterus - Anatomy & Physiology|Uterine lumena]] do not fuse.   
 
* [[Uterus - Anatomy & Physiology|Uterine lumena]] do not fuse.   
 
** The two uterine horns continue into seperate [[Cervix - Anatomy & Physiology|cervices]]
 
** The two uterine horns continue into seperate [[Cervix - Anatomy & Physiology|cervices]]
 
** Open separately into a single [[Vagina and Vestibule - Anatomy & Physiology|vagina]].
 
** Open separately into a single [[Vagina and Vestibule - Anatomy & Physiology|vagina]].
* Membrane covers [[Vagina and Vestibule - Anatomy & Physiology|vaginal]] opening except at oestrus and during [[Reproductive System - Anatomy & Physiology#Parturition|parturition]].
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* Membrane covers [[Vagina and Vestibule - Anatomy & Physiology|vaginal]] opening except at oestrus and during [[Normal Parturition - Anatomy & Physiology|parturition]].
  
 
=== Puberty and Sexual Maturity ===
 
=== Puberty and Sexual Maturity ===
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==== Gestation ====
 
==== Gestation ====
  
* Long [[Reproductive System - Anatomy & Physiology#Gestation|gestation]] period: 111 days.
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* Long gestation period: 111 days.
  
 
==== Litter ====
 
==== Litter ====
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[[Category:Small Mammal Reproduction]]
 
[[Category:Small Mammal Reproduction]]
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[[Category:Bullet Points]]

Latest revision as of 13:50, 5 July 2012

MALE

Scrotum and Testes

  • Only a very slight scrotal region is visible externally (no true scrotum).
  • Thin-walled scrotal diverticula extend cranially on either side of the base of the penis.
  • Each diverticulum is occupied by the tail of the epididymis.
  • On either side of the anus are two postanal sacs.
    • Caudal epididymis can lie in the postanal sacs.
  • Testes and head of the epididymis is in the region of the inguinal ring.
  • Large fat body extends cranially into the abdominal cavity from the cranial pole of each testis.


Accessory Sex Glands

Vesicular Glands

  • Very long and tubular.

Prostate Gland

  • Paired large ventral lobes and paired small dorsal lobes.

Bulbourethral Glands

  • Dorsolateral to ischiocavernosus muscles.
    • Ischiocavernosus muscles are enormous, swelling on either side of the rectum and meeting over its top.

Penis

  • Penis points caudally when relaxed and cranially when erect.
  • 1.5cm in length
  • Sigmoid flexure
  • Os penis in the distal portion.
    • The small supporting bone is known as the baculum.


Copulation

  • Spermatogenesis occurs at about 2-3 months.
  • Copulatory maturity is not until about 8 months.
  • Breeds all year round.
  • Copulatory plug at mating.

FEMALE

Reproductive Tract

Puberty and Sexual Maturity

  • Puberty at ~8 months
    • Puberty can be same year as birth, but if the chinchilla is born late in the year it will not reach puberty until the next breading season.


Oestrous Cyclicity

  • In the Northern Hemisphere the breeding season is November-May.
  • Seasonally polyoestrus with a mean cycle of ~40 days.
  • Post-partum oestrus.
    • Often two litters per year, three are possible.
  • Breeding life is ~10 years.


Gestation and Offspring

Gestation

  • Long gestation period: 111 days.

Litter

  • Litter size 1-6
  • Precocious offspring
    • Weaning age is 6 weeks.

Mammary Gland

  • Three pairs
    • One inguinal pair
    • Two lateral thoracic
  • Teats protrude sideways, allowing the young to sit beside the dam and suckle.