ALAT Breeding and Reproduction 4 — Questions and Answers
Question 1: Which method is used to determine if a female rabbit has been successfully bred?
- Vaginal smear
- Palpation of the abdomen at 10-14 days post-mating (Correct answer)
- Urinalysis
- Blood progesterone test only
Correct answer: Palpation of the abdomen at 10-14 days post-mating
Abdominal palpation at 10-14 days post-mating is the standard method to detect embryos in rabbits.
Question 2: What is the term for the reabsorption of embryos that can occur in mice and rats under stressful conditions?
- Pseudopregnancy
- Embryonic diapause
- Embryonic resorption (Correct answer)
- Luteal regression
Correct answer: Embryonic resorption
Embryonic resorption is the process by which embryos are reabsorbed by the dam, often triggered by stress or overcrowding.
Question 3: Guinea pigs are unique among common lab rodents because their young are born:
- Hairless and blind (altricial)
- Fully furred and mobile (precocial) (Correct answer)
- Requiring immediate fostering
- After only 30 days gestation
Correct answer: Fully furred and mobile (precocial)
Guinea pig pups are precocial, born fully furred, eyes open, and able to move shortly after birth.
Question 4: What does the acronym 'SPF' mean in the context of a breeding colony?
- Standard Phenotype Female
- Specific Pathogen Free (Correct answer)
- Selective Pathogen Filter
- Staged Production Facility
Correct answer: Specific Pathogen Free
SPF stands for Specific Pathogen Free, meaning the colony is free of a defined list of pathogens.
Question 5: In a trio mating system for mice, the recommended composition is:
- One female and two males
- Two females and one male (Correct answer)
- Three females
- Two males and two females
Correct answer: Two females and one male
A trio consists of two females and one male, maximizing reproductive output per male.
Question 6: Which of the following best describes 'outbred' stocks used in research?
- Genetically identical individuals from brother-sister mating
- Heterogeneous populations maintained to maximize genetic diversity (Correct answer)
- Animals cloned from a single founder
- Transgenic animals with a specific inserted gene
Correct answer: Heterogeneous populations maintained to maximize genetic diversity
Outbred stocks are maintained with systematic randomization to preserve genetic heterozygosity across the population.
Question 7: The Whitten effect in mice refers to:
- Suppression of estrus by dominant females
- Synchronization of estrus cycles upon introduction of male pheromones (Correct answer)
- Delayed implantation after mating
- Spontaneous abortion caused by a strange male
Correct answer: Synchronization of estrus cycles upon introduction of male pheromones
The Whitten effect is the synchronization of estrous cycles in female mice triggered by exposure to male urine pheromones.
ALAT Breeding and Reproduction 4
Which method is used to determine if a female rabbit has been successfully bred?