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Facts About Mice and Rats | Mice | Rats | Lifespan | 1.5-3 years | 2.5-3.5 years | Cage temperature range | 65-80°F | 65-80F | Relative humidity range | 40-70% | 40-70% | Breeding age | 50 days (male) | 65-110 days | | 50-60 days (female) | | Estrous cycle | 4-5 days | 4-5 days | Gestation period | 19-21 days | 21-23 days | Litter size | 10-12 young | 6-12 young | Weaning age | 21-28 days | 21 days |
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