Amazing Rodent Facts! Do you know how long a rat lives for? How much a guinea pig weighs? Or even, how much water does a mouse drink each day? Here are all the facts and figures you need to know about rodents - rats, mice and guinea pigs. Rats Mice Guinea Pigs Life Span 2~4 years 1~3 years 4~5 years Food Consumption 10g/100g/day 15g/100g/day 6g/100/day Water Consumption 10ml/100g/day 15ml/100g/day 10ml/100g/day Breeding Onset – Male 65~100 days 50 days 3~4 months Breeding Onset – Female 65~110 days 50~60 days 2~3 months Pregnancy 21~23 days 19~21 days 59~72 days Litter Size 6~12 10~12 2~5 Weaning Age 21 days 21~28 days 14~21 days Weight 250~520g 20~40g 700~1200g Table courtesy of Dr Bob Donely BVSc MACVSc