Biology Flashcards
What are the environmental conditions (5) required for housing rodents?
Ventilation
Adequate temperature
Humidity (45-65%)
Lighting (low light level within cages)
Noise (background noise <50 dB) - reduces impact of loud noises
How should mice and rats be fed?
Mice should have freely available food (rats too, although this could lead to obesity).
Both ingest faecal pellets to reabsorb nutrients
How do rodents cope with poor visual activity?
Primarily rely on olfaction, hearing and whiskers
Mouse reproductive biology:
Become sexually mature at 6-7 weeks
Pregnancy lasts for 19-21 days. Fetuses can be detected using ultrasound or by gentle palpitation of the abdomen by 7-10 days
Most have 10-16 in each litter
Male mice have an obvious scrotum. Can differentiate by looking at the ano-genital distance (larger in males)
How many generations of mating are required for homozygous inbred mice strains?
20 (approx.) brother x sister, or father x daughter
What are the average body weights of male and female adult mice?
Male: 20-40g
Female: 25-40g
What is the typical breeding onset for male and female mice?
Male: 50 days
Female: 50-60 days
What is the gestation period for mice?
19-21 days
What is the typical weaning age for mice?
21-28 days
Rat reproductive biology:
Become sexually mature at 6-7 weeks of age
Pregnancy lasts for 21-23 days
Fetuses can be detected using ultrasound by 9-10 days and by gentle palpitation a few days later
Number of pups around 10-16
What is the average body weight of adult rats?
Male - 250-450g
Female - 250-300g
What is the breeding onset of rats?
65-110 days for both male/female
What is the gestation period of rats?
21-23 days
What is the weaning age for rats?
21 days
