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Physiologic
Temperature :	(R) 37.7°C (99.85°F)
Diploid number :	42
Respiratory rate/minute :	71-146
Tidal volume :	0.6 - 2.0 mL
Oxygen use :	0.68 - 1.10 mL/g/hr
Body surface area cm2 :	10.5 (weight in grams)2/3
GI transit time :	12 - 24 hr
Heart rate/minute :	250-493
Blood pressure :	84-134 mm Hg
Daily urine output (average) :	23-33 mL
Food Intake :	5-6 gm per ea. 100 gm per day
Water Intake :	10-12mL per 100 gm per day
Weight (male average adult) :	250-550 gm
Weight (female average adult) :	225-400 gm
Nipples (found only on females):	Average 6 pairs
Life span (average) :	24-40 months

Reproduction
Puberty :	6-8 weeks
Oestrous cycle :	Polyoestrous
Estrous period :	approx. 12 hours
Duration of cycle :	4-5 days
Gestation :	21-23 days
Size of litter :	approximately 8-14 pups
Birth weight:	5-6 gm
Eyes open :	10-12 days
When weaned :	approximately 4 weeks
Return of oestrus cycle postpartum :	within 24 hours
Composition of Doe’s milk :	13.0% fat , 9.7% protein , 3.2% lactose
Important male anatomic notation	open inguinal canals

Hematologic
Total Blood volume :	50-70mL/kg
red blood cells (RBC) (x 10to6th/µl) :	5.4-8.5
hemoglobin (Hg) :	11.5-16.0 g/dl
hematocrit (Hct) :	37-49%
platelets (PLT) (x 10³/µ1) :	450-855
white blood cells (WBC) (x 10³/µ1) :	4.0-10.2
FOR PURPOSE OF BLOOD SAMPLES
Single Sample:
2-3 mL  a
*Note: exsanguination occurs at 8-12mL  a

Electrolyte and Chemistry
Serum glucose :	50-135 mg/dl
Serum calcium :	5.3-13.0 mg/dl
Serum protein :	5.6 -7.6 g/dl
Creatinine :	0.2-0.8 mg/dl
Blood urea nitrogen (BUN) :	15-21 mg/dl
Urine:	pH (acidity/alkalinity of solution) 7.3-8.5	SG (Specific Gravity) 1.04-1.07

Environment Requirements
Room Temperature :	65°-79°F / 18°-28°C
Relative Humidity :	30% - 70%
Housing Space :	40 in.²   per 300 gm. wt. of rat

Values expressed here are adaptations from references listed on References page of the Rat Health Guide Index. Normal variations may occur within the rat population. Values from blood or tissue samples may vary slightly, based on the Lab the specimens are sent to and its equipment calibrations.

^aEquals approximate values.

Posted on June 20, 2003, 14:17, Last updated on September 25, 2009, 13:59 | Basics