Birth to Weaning Figure 4

Pup Development- Week Four

This is the last week that the babies need to be with their mother. Even if you see occasional nursing after day 28, the babies are weaned.

By 5 weeks of age the male and female babies will need to be separated. Rats can become sexually mature between the ages of 5-6 weeks.

Days 22-28

Now that the babies are in their fourth week of development they are filled with energy and curiosity. Their balance has improved and they climb the wire sides of the cage and will often hang from the tops. Wrestling and eating are the two preferred activities.
The dumbo babies have fully developed ears. Their faces are becoming more elongated as they grow.
Day 22

Instead of always sleeping together in a giant huddle, you may see them sleeping in two or three groups on different levels of the cage. Mom is nursing them less often. The babies are now using the water bottle, eating lab block and seed mix, and joining mom in eating snacks. Day 23

Babies often go through a molt at about this time and may have strange color or texture “patterns” in the coat as new hair comes in. Rex offspring may develop bald spots in certain areas. Day 24

It is essential that the babies be handled
every day to socialize and get them ready for their new homes. At this age they are very active, friendly, and playful. They love to be wrestled with and “chased” using your hand. When handling the babies it is wise to get them used to being on their backs and to having their feet, ears and mouths touched. This makes it easier to give them health checks as adults.
Day 25

They learn what is safe to eat from what Mom ate while she was pregnant and from what she eats now. Give them a variety and take out any uneaten perishable food. Day 26

Keep in mind that the mother rat is the one doing all of the work. A happy healthy mom will contribute to more healthy and happy offspring.
Reward her by making sure she gets quality time with you and occasional time away from her litter. Providing her with special healthy snacks that she can eat without being swarmed by her babies will be greatly appreciated.
Day 27

The babies are now weaned.

Their basic personalities are pretty well established, and each day they show increased individuality. It is amazing to look at the babies in the first week of development and then compare them at 4 weeks of age.

Pup rats mature quickly. Remember to separate the males and the females by the time they are 5 weeks old to prevent any pregnancies. You can leave the females in with their mother. The boys will need their own cage.

Day 28

Photos by Joanne “Bella” Hodges


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