Jax Handbook - Chap 13 Breeding Strategies & Techniques Flashcards
True or False: Males reach sexual maturity later than females.
True
Males usually reach sexual maturity by 6 weeks, females by 4–6 weeks.
How long is the murine estrous cycle?
a. 4 to 5 days
b. 7 days
c. 8 days
d. 10 days
a. 4 to 5 days
What is the average gestation length for mice?
a. 14-16 days
b. 18-21 days
c. 22-25 days
d. 26-28 days
b. 18-21 days
True or False: Weaning age can vary depending on the strain of the mice.
True
Most strains are weaned at 21 days, some at 28 days. Do not remove pups from mother before 17 days unless they are transferred to a foster mother.
True or False: The post partum estrous is the estrous period that females enter within a few hours of giving birth.
True
What is the average time for a generation?
a. 6 weeks b. 7 weeks c. 8 weeks d. About 10 weeks
d. About 10 weeks
What is the reproductive lifespan for the female?
Strain dependent.
For inbred strains, fecundity usually begins to decrease with the 3rd litter. By 6–8 months, some females become infertile, and litter size for most females of most strains has diminished to the point that it is more economical to set up a new breeding pair
What is the reproductive lifespan for the male?
Strain dependent.
Fertility in some strains decreases starting at 10 months
When does implantation occur?
Implantation normally occurs during the fifth day after conception.
However, if a female is nursing, implantation may be delayed for more than a week, during which time embryonic development is held in suspension.
True or False: Delayed implantation may occur if the female is nursing a litter.
True
Cage location may decrease breeding performance, and mothers may
a. Cannibalize pups b. Resorb litters c. Stop breeding d. All of the above
d. All of the above
What is the most common lighting cycle for breeding?
The most common cycles are 14:10 (on:off) and 12:12.
True or False: Falling barometric pressure can cause some strains to become hyperactive, reducing breeding performance.
True
What is the thermoneutral temperature for mice?
About 27-28C (80-82F)
What air quality measures may help promote successful breeding?
a. Have a “no perfume” policy for those who are working with mice b. Keep mice away from noxious fumes c. Using clean forceps or clean/new gloves between cages d. All of the above
d. All of the above
True or False: Wild-derived mice may be more sensitive to handling stress.
True