Rodent Reproductive Patterns

Published: July 09, 2007

Age of onset of puberty and breeding life

 

 

 

 

Rat

 

Mouse

 

Guinea pig

 

Sexual maturity in weeks (male)

 

6-10

 

6-8

 

10-12

 

Sexual maturity in weeks (female)

 

8-12

 

6-8

 

10-12

 

Breeding life  in months (male)

 

9-12

 

9

 

24

 

Breeding life  in months (female)

 

9-12

 

 9

 

 24

 

 

Female reproductive cycles

 

 

 

 

Rat

 

Mouse

 

Guinea pig

 

Estrous cycle length (days)

 

4-5

 

4-5

 

16

 

Estrus duration (hr)

 

10-20

 

10-20

 

6-11

 

Estrus onset to ovulation (hr):

 

 8-11

 

2-3

 

 10

 

Fertilization life of ovum (hr):

 

10-15

 

15

 

8-26

 

Fertilization life of sperm in female tract (hr)

 

14

 

6

 

20-22

 

Presence of copulatory plug in female tract (hr)

 

12-24

 

18-48

 

 9-18

 

Ovulation rate (egg number)

 

10-20

 

6-10

 

3-4

 

Pseudopregnancy (days)

 

12

 

 12

 

none

 

 

 

Daily sperm production and epididymal sperm reserves of growing, sexually rested Wistar rats. Although there is a small daily sperm production by 40 to 50 days it is not until 75 days that there are optimum production and sperm reserves.

 

 

 

 

Age in days

 

 

 

40

 

45

 

50

 

75

 

100

 

Weight body (g)

 

201

 

228

 

298

 

399

 

499

 

Weight testes (g)

 

1.7

 

2.0

 

2.8

 

3.5

 

3.7

 

Daily sperm  production 106/g testis

 

2.0

 

10

 

15

 

24

 

24

 

Daily sperm  production 106/g rat

 

3.5

 

19

 

40

 

80

 

85

 

Sperm reserves epididymis head and body (106)

 

1

 

22

 

256

 

282

 

 

 

Sperm reserves epididymis tail (106)

 

1

 

3

 

267

 

422

 

 

 

 

Male copulatory patterns

 

 

 

 

Rat

 

Mouse

 

Guinea pig

 

Mounting time in seconds

 

5-10

 

15-20

 

5

 

Pre-ejaculatory intromissions

 

10-20

 

 5-20

 

1-13

 

Ejaculations per mating

 

7

 

1-3

 

1

 


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