Baby Rat Development from Birth to 6 weeks
By Karen Robbins
Newborn. They are bright pink and only weigh 6–8 grams (not much more than a nickel). Their eyes and ear canals are sealed. The light spot on their left side is a tummy full of milk. | 1 Day. The babies are already showing pigment. Go to more photos of 1-day-old rat babies. | 2 Days. The babies are showing more color pigment and have clearly grown in size and weight. |
3 Days. Each day more pigment shows through. | 4 Days. | 5 Days. |
6 Days. They are starting to get some peach fuzz hair. These are all Russian Blue. | 7 Days (1 week). | 8 Days. |
9 Days. Their coats are really starting to come through. | 10 Days. | 11 Days. |
12 Days. | 13 Days. | 14 Days (2 weeks). They opened their eyes today and will really begin to explore their cage. |
15 Days. | 16 Days. | 17 Days. |
18 Days. Practicing their washing. They are at the super cute balls-of-fluff stage. The babies are eating a variety of foods but still need mom’s milk. | 19 Days. | 20 Days. |
21 Days (3 weeks). | 22 Days. | 23 Days. |
24 Days. | 25 Days. They are starting to grow very quickly and they spend their waking hours doing lots of playing. | 26 Days. |
27 Days. | 28 Days (4 weeks). Mom is in the process of weaning them. | 29 Days. |
30 Days. | 31 Days. | 32 Days. |
33 Days. | 34 Days. | 35 Days (5 weeks). They are continuing to grow very quickly and you will start to notice a size difference between males and females. |
36 Days. | 37 Days. | 38 Days. |
39 Days. | 40 Days. | 41 Days. |
42 Days (6 weeks). The babies are well developed, completely weaned, and ready to go to their permanent homes to be wonderful pets. Males and females MUST be separated by this age. |
Go to Sexing 101.
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Updated November 2, 2015
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How long does it take for baby rats to grow hair?
Baby Rats – Week One
Pigment starts to accumulate in their skin almost immediately after birth. But it won't be until day five that they begin to get their first peachy fuzz of hair. And until they're four or five days old, a rat pup is pretty much immobile.
Do newborn rats have fur?
Although they are born furless, blind, and deaf, neonatal rats have some sensory capacities and behavioral abilities that are adaptive to and functional in the terrestrial environment. For instance, they have olfaction and are able to root for, attach to, and suckle at the dam's nipple.
How can I tell how old my baby rats are?
While it's not a foolproof method, observing the rat's front incisors indicates a rat's age when wondering how old is my rat. Younger rat tooth coloration will be a pale yellow shade. As rats age, their tooth color will darken. In adult rats, the most common tooth color is dark yellow.
What does a 2 week old rat look like?
AFRMA - Baby Rat Development from Birth to 6 weeks. Newborn. They are bright pink and only weigh 6–8 grams (not much more than a nickel). Their eyes and ear canals are sealed.