Difference between revisions of "Gerbil Reproduction - Anatomy & Physiology"
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| − | + | == Male == | |
| − | + | Anogenital distance in the adult is ~10mm (twice that of the female). | |
| − | + | === Penis === | |
| − | |||
| − | = | ||
| − | |||
| − | == | ||
* Os penis lies within the tissue of the penis. | * Os penis lies within the tissue of the penis. | ||
| − | == Testes == | + | === Testes === |
* Two testes in an external scrotum. | * Two testes in an external scrotum. | ||
| Line 19: | Line 15: | ||
* In the young animal, scrotum is obvious and dark in colour. | * In the young animal, scrotum is obvious and dark in colour. | ||
| − | == Reproductive Behaviour == | + | === Reproductive Behaviour === |
* Abdominal sebacious gland is large and apparent at ~4 weeks. | * Abdominal sebacious gland is large and apparent at ~4 weeks. | ||
| Line 27: | Line 23: | ||
| − | == Mammary Gland== | + | === Mammary Gland=== |
* Teats are absent. | * Teats are absent. | ||
| − | + | == Female == | |
| − | |||
| − | = Female = | ||
| − | == Reproductive Tract == | + | === Reproductive Tract === |
| − | * [[ | + | * [[Uterus - Anatomy & Physiology#Anatomical_Types_of_Uteri|Bicornuate uterus]] |
| − | * Two channels of the [[ | + | * Two channels of the [[Cervix - Anatomy & Physiology|cervix]] separated almost to the single entrance into the [[Vagina and Vestibule - Anatomy & Physiology|vagina]]. |
| − | == Puberty and Sexual Maturity == | + | === Puberty and Sexual Maturity === |
* Sexual maturity is at ~9-12 weeks. | * Sexual maturity is at ~9-12 weeks. | ||
| − | == Oestrous Cyclicity == | + | === Oestrous Cyclicity === |
* Polyoestrous | * Polyoestrous | ||
| − | * [[ | + | * [[Oestrous Cycle - Anatomy & Physiology|Oestrous cycle]] length: 4-6 days |
* Post-parturient oestrus | * Post-parturient oestrus | ||
| − | * Spontaneous [[ | + | * Spontaneous [[Ovulation - Anatomy & Physiology|ovulator]]. |
| + | === Breeding Characteristics === | ||
| − | + | * Monogamous (in contrast to [[Rat Reproduction - Anatomy & Physiology|rats]] and [[Mouse Reproduction - Anatomy & Physiology|mice]]). | |
| − | |||
| − | * Monogamous (in contrast to [[ | ||
* Mating usually occurs in the evening. | * Mating usually occurs in the evening. | ||
| − | * Copulation plug is small and lies deep in the [[ | + | * Copulation plug is small and lies deep in the [[Vagina and Vestibule - Anatomy & Physiology|vagina]], so cannot easily be detected. |
| + | === Gestation and Offspring=== | ||
| − | == Gestation | + | ==== Gestation ==== |
| − | * | + | * Gestation period is 22-26 days. |
| − | |||
* May produce a litter every 30-40 days and can produce a total of 10 litters. | * May produce a litter every 30-40 days and can produce a total of 10 litters. | ||
* Maximum breeding age is 20 months, but usually the time between the first and last litter is ~1 year. | * Maximum breeding age is 20 months, but usually the time between the first and last litter is ~1 year. | ||
* Pseudopregnancy may occur. | * Pseudopregnancy may occur. | ||
| + | |||
| + | ==== Litter ==== | ||
| + | |||
| + | * Mean litter size is 4-5. | ||
* Altricial offspring. | * Altricial offspring. | ||
** Hairless, blind and virtually helpless. | ** Hairless, blind and virtually helpless. | ||
** Ears open at 5 days. | ** Ears open at 5 days. | ||
** Eyes open at 16-17 days. | ** Eyes open at 16-17 days. | ||
| − | ** Cannibalisation/ | + | ** Cannibalisation/abandonment is rare. |
| + | |||
| + | === Mammary Gland === | ||
| + | * 4 pairs of teats. | ||
| − | |||
| − | + | [[Category:Small Mammal Reproduction]] | |
| + | [[Category:Bullet Points]] | ||
Latest revision as of 13:50, 5 July 2012
Male
Anogenital distance in the adult is ~10mm (twice that of the female).
Penis
- Os penis lies within the tissue of the penis.
Testes
- Two testes in an external scrotum.
- Testes descend at 30-40 days.
- Active spermiogenesis and mating apparent from 10 weeks of age.
- In the young animal, scrotum is obvious and dark in colour.
Reproductive Behaviour
- Abdominal sebacious gland is large and apparent at ~4 weeks.
- Rubbed along the ground to mark territorial boundaries.
- Form monogamous pairs/Harems
- Fighting among males is common
Mammary Gland
- Teats are absent.
Female
Reproductive Tract
- Bicornuate uterus
- Two channels of the cervix separated almost to the single entrance into the vagina.
Puberty and Sexual Maturity
- Sexual maturity is at ~9-12 weeks.
Oestrous Cyclicity
- Polyoestrous
- Oestrous cycle length: 4-6 days
- Post-parturient oestrus
- Spontaneous ovulator.
Breeding Characteristics
- Monogamous (in contrast to rats and mice).
- Mating usually occurs in the evening.
- Copulation plug is small and lies deep in the vagina, so cannot easily be detected.
Gestation and Offspring
Gestation
- Gestation period is 22-26 days.
- May produce a litter every 30-40 days and can produce a total of 10 litters.
- Maximum breeding age is 20 months, but usually the time between the first and last litter is ~1 year.
- Pseudopregnancy may occur.
Litter
- Mean litter size is 4-5.
- Altricial offspring.
- Hairless, blind and virtually helpless.
- Ears open at 5 days.
- Eyes open at 16-17 days.
- Cannibalisation/abandonment is rare.
Mammary Gland
- 4 pairs of teats.