Baby Rats: 10 Fascinating Facts & Pictures

Fully grown rats are cute, sure. But something that’s even cuter than them is the baby rat. Most people know a thing or two about these adorable little creatures, but there are also a lot of things that people do not know about them. For instance, do you know what they’re called, whether they’re born with hair or teeth, or if they’re born blind?

If you’d like to learn more about the adorable baby rat, you’ve come to the right place. Because today, we’re going to take a closer look at these adorable little creatures by going over the top 10 facts about them.


1. Baby rats are called pups

When you hear the word “pup” you might think of a baby dog, but did you know that the offspring of rats are called pups as well?

They’re sometimes also referred to as pinkies, due to their coloring at birth.

A group of baby rats is called a litter.


2. Rats are born hairless, deaf, and blind

When rats are born, they’re completely deaf, blind, and hairless. It’s because of the fact that they’re born hairless that they’re often pink at birth.

Since rats are blind and deaf, they’re very vulnerable at birth. They’re protected by their mom, who keeps a watchful eye on them. Because their babies are so vulnerable, mommy rats can get quite protective of them, even towards their human owners. Because of this, it’s recommended that you do not disturb the mother and the litter for the first 7 days. This is especially the case if it’s the mother’s first litter.


3. After 6 days they start to grow hair

a 1-week old rat. image credit: forsaken fotos

About 5 to 6 days after being born, baby rats will start to grow hair. They will lose their unique pink color and will start to get a little bit of peach fuzz going. Of course, it will still take a while for them to grow a full coat, but the beginnings are there.

After about 9 days, their coat really starts to show. It will no longer be a peach fuzz, but it will start to look like the fur of a real rat. As time goes on, their coat will fill in more until they’re characteristic fur balls that we’ve all come to love.


4. They open their eyes 15 days after being born

While rats are born blind, they do not stay blind their entire lives. They open their eyes about 15 days after being born. This is also when they start exploring their surroundings.

However, even though rats do not stay blind, their vision never really develops to become all that great. Rats stay colorblind their entire life and can not see very well, even when they’re fully grown.

The reason why they don’t have very good eyesight is that they’re largely nocturnal and rely more on their sense of smell and hearing than on their sight.


5. After 4 weeks they start to eat solids

When rats are born, they’re fed milk by their mother. This is the case for all mammals, and rats are no exception. Their mother’s milk allows the baby rats to grow very quickly. However, rats wean from their mother quite fast.

Only 4 weeks after being born, rats will already start eating solids.

If you’re curious about what to feed a baby rat, good foods to give them include those that are soft and easy to chew such as bananas. In addition, it’s also good to introduce them to foods that will allow them to practice gnawing, such as small pieces of peeled apple or grape.

Once they start eating solid foods, it won’t be long until they can eat everything that a fully-grown rat can. Foods that they can eat at that point include:

  • Fruits. Apples (no seeds), strawberries, blueberries, oranges, bananas
  • Vegetables: Kale, broccoli, cucumber, bell pepper, romaine lettuce
  • Meats: chicken, fish, low-fat beef
  • Other: hard-boiled eggs, nuts, seeds

6. After 6 weeks they are fully grown

image source: maxpixel

Baby rats grow up remarkably fast. Only 6 weeks after being born, they’ve become fully grown adults and are ready to be sent to their new loving homes. It’s also at this time that you can fully see what type of rat the pup is.

As a result of them being fully grown, it’s important that they get separated at this age into groups of males and females. The reason why this is important is that otherwise, they will start to breed and produce even more baby rats.


7. Rats can have many pups

a big group of baby rats

Rats are capable of reproducing extremely quickly. They can have up to 12 pups in a single litter, although they generally have between 5 and 10. On top of that, female rats can have up to 7 litters in a single year, which means that they can have up to 84 pups in one year!

If you take into account the fact that rats are fully grown at 6 weeks and that they can then start having litters of their own, it’s easy to see why rat populations can grow so quickly.


8. Rats are born with teeth

Many animals are born without teeth, but not rats. Baby rats have teeth when they’re born. However, their teeth are not in the same formidable state that they are when they’re fully grown. The teeth of the pups are quite small and fragile and definitely not capable of chewing through all the stuff that adults can.

Another interesting fact is that the teeth of baby rats are white, whereas the teeth of adult rats are yellow. The reason why they’re yellow in adults is not that they’re dirty, but because of their enamel!


9. Baby rats are incredibly small

When rat pups are born they only weigh between 6 to 8 grams (0.21 to 0.28 ounces). They’re also very tiny, at around 2 to 4 inches in length.

Once they’re fully grown, they become much bigger. For comparison, a fully grown rat weighs between 0.5 to 1 pound (230 to 450 grams) and is about 10 inches in length, excluding the tail.


10. Rats are born with their tail

Rat pups are born with their tail, but their tail is much shorter relative to the size of their body when they’re born than when they’re fully grown.

When they’re fully grown, their tail is almost as long as the entire rest of their body. When they’re a baby, it’s quite a bit smaller.


Final words

So, there you have it, the top 10 facts about baby rats! I hope you learned something new today. If you can’t get enough of these adorable little rat pups and want more, I suggest checking out this video of a timelapse of rats from the moment they’re born until they’re fully grown adults. It gives a great overview of how rats develop.

Jesse A.