Table 4.2.

Selected Normative Data for the Rat^a

ADULT
Weight
Male	300–500 g
Female	250–300 g
Life span	2.5–3 years
Body temperature	37.5°C
Basal metabolism rate (400-g rat)	35 kcal/24 h
Chromosome number (diploid)	42
Puberty	50 ± 10 days
Gestation	21–23 days
Litter size	8–14
Birth weight	5–6 g
Eyes open	10–12 days
Weaning	21 days
Food consumption/24 h	5 g/100 g body weight
Water consumption/24 h	8–11 ml/100 g body weight
CARDIOVASCULAR
Arterial blood pressure
Mean systolic	116 mmHg
Mean diastolic	90 mmHg
Heart rate	300–500 beats/min
Cardiac output	50 ml/min
Blood volume	6 ml/100 g body weight
RESPIRATORY
Respirations/min	85
Tidal volume	1.5 ml
Alveolar surface area (400 g rat)	7.5 m2
RENAL
Urine volume/24 h	5.5 ml/100 g body weight
Na+ excretion/24 h	1.63 mEq/100 g body weight
K+ excretion/24 h	0.83 mEq/100 g body weight
Urine osmolarity	1659 mOsm/kg of H2O
Urine pH	7.3–8.5
Urine specific gravity	1.04–1.07

^aData from Baker, 1979, Bivin et al., 1979.