Pet stores often do little in the way of seperating their rats into gender groups, and as a result, it’s likely that the female you just purchased is pregnant.
It’s unfortunate that unplanned litters happen, but they do. The first step is not to panic: there are several steps you can take to ensure that the mother has a safe birth, and that she raises a happy litter.
1. At what age do rats hit sexual maturity?
2. What is the gestation period?
3. How do I tell if my rat is pregnant?
4. Okay, I think she’s pregnant. What now?
5. What constitutes a good maternity setup?
6. What should I feed the mother?
7. What will the delivery be like?
8. What if she runs into complications?
9. What if I need to bottle feed the babies?
10. How can I tell if the babies are getting enough to eat?
11. When can I start handling the babies?
12. How can I sex the babies?
13. When can I wean the babies?
14. When can the babies leave their mother?
Though rats are not considered fully grown until 7-10 months of age, they can become sexually mature at as young as four weeks. Rats generally become sexually active at about five weeks, and should be seperated from littermates of the opposite gender at this age. If you’ve purchased a female who was kept in a mixed sex group and is over 5 weeks of age, there is a good chance that she is pregnant.
The usual gestation period for a rat is 18-28 days. Most rats give birth sometime around the 21-23 day mark. If your rat is obviously pregnant and hasn’t given birth by about the 25th day, it is probably best to consult a vet.
Most pregnant females develop large bellies by the third week of pregnancy- some a little earlier, and some a little later. Some mothers don’t show at all until a couple of days before giving birth, when they very suddenly look like they’ve swallowed a tennis ball. Her nipples will become more prominent, and she will begin showing some nesting behavior.
First, most breeders will agree that it is best to seperate her from her cagemates. Female rats tend to squabble over babies, and some females will steal babies from lower ranking females. This can lead to extreme stress in the mother, and starvation and death of the kittens. For the safety and well being of all involved, it’s best to set up a safe, quiet maternity cage for the mother to raise her babies free from being hassled by the other females.
One level, solid containers are preferred for very young babies. A 20 gallon aquarium or a modified plastic bin will do just fine. The mother should be provided with a nest box and nesting material. A covered basket, shoebox, or plastic igloo will work well. Nesting material can be shredded paper, paper towels, or cloth. When using cloth, make sure that no strings can come loose and wrap around a leg, tail, or neck. If the mother enjoys using a wheel, she should have access to one. Of course, food and water should always be available.
In addition to her normal diet (lab blocks or high quality dog food with a good grain mix, and plenty of fruits and vegetables) it’s a good idea to add protein to her diet as soon as you find out she’s pregnant and throughout the time she’s nursing. Generally, with pregnant and nursing mothers, I have their normal food and some fresh food available to them at all times, and they’re given a couple of the following things twice a day:
Oatmeal or Baby Cereal in Soy milk or KMR(Kitten Milk Replacement)
Scrambled or boiled eggs
High quality dry kitten food
Cooked meat, especially chicken, liver, turkey, or fish
Wet dog or cat food
Generally, with pregnant moms, if she wants it, she gets it. Moms will get leftovers from my dinner, some sweets- anything she wants within reason.
Mothers usually choose to deliver early in the morning or late at night, though I’ve had mothers give birth at all hours. Most mothers give birth in a sitting position, with their backs propped against a wall, and their hind legs spread. They help the baby leave the birth canal with their hands, cleaning the blood and afterbirth and stimulating the baby with their tongue as they go. Some mothers will eat any stillborn young- this is normal and you should leave her to it. It’s just her way of recycling the protein and keeping the nest clean.
Rats can have anywhere from 1-20+ babies in a litter, but the average is about 8-12. The babies will be born blind, naked, and deaf. They will not be able to see or hear until around 2 weeks of age, and they will grow their fur at about a week.
Chances are, she won’t unless she’s extremely young, or extremely old. That said, complications can occur, and here are some signs to look for if something is wrong:
1. Excessive blood- of course, some blood is normal, but if it really seems to be gushing out that’s cause for concern. If, for instance, you see some blood on her nesting material, maybe a little on her hands and coming from her vagina, that’s normal- but if her whole bottom is covered in blood, more than a handful or so of bedding has blood on it, and she’s got it everywhere, that *isn’t* normal.
2. Extreme straining or discomfort- If you see her leaving her nest while in active labor and straining, lying on her belly and back and pushing really hard, looking dazed, or in a lot of pain, there is probably a baby that’s breached or too large to come through, and that’s definitely cause for concern.
3. Prolonged pregnancy- if she goes longer than she should with a very large belly- more than a week to a week and a half, she may have necrotic fetuses inside of her that will need to be removed surgically.
If you see any of those things, get her to the nearest vet immediately- don’t wait, because you can lose a mother very quickly from birth complications. She may need an emergency C-section (or oxytocin)to save her life. If you don’t have a good rat vet now, you may want to start calling around and get one lined up just in case.
Hand raising baby rats is extremely difficult, but if the mother dies or is unable to feed them, you may have to try. It’s a good idea to have a heating pad, some KMR, and some small tipped syringes on hand just in case. These links will provide the how-to’s:
Until they grow their fur, you can look for a “milk band” on the abdomen. Baby rats have very translucent skin, and the stomach will be visible and white when full of milk.
In most cases, right away. Baby rats must be handled regularly from an early age in order to ensure that they grow into friendly, well socialized adults.
Unlike hamsters, rats are unlikely to cannibalize their healthy young. Judge the emotional state of the mother before handling the young. If you disturbing the nest seems to overly stress her, give her a day or two to settle down before picking up the babies. If, after this time, she still seems overly stressed about you picking up the babies, you’ll have to do it anyway- the only way to ensure that the babies grow up to be good pets is to start handling them from a young age. Some otherwise friendly mothers become aggressive when raising their litter- this is normal. She’s just being a good mother and protecting her kittens, and this is not to be taken personally. Once her babies are weaned, she’ll likely return to her old friendly self. If she tries to bite- and some mothers will- you can use gloves to take the babies out of the cage or distract the mother with food. Once the babies are out, you’ll need to take the gloves off to get them used to your scent and the feel of your skin.
For the first 2-3 days, handle the babies for only a few minutes at a time. I usually sex the babies on the first day, and check them two or three times a day for milk bands up until their fourth day. After that time, I begin holding them longer. I generally take out each baby for 20 minutes at a time, twice a day until the second week. I hold each one for 10 minutes while I read or watch television, or, if I have something to do around the house, I put on a pouch under my shirt, or a shirt with a pocket, and walk around with them in it. After two weeks, I extend the time a little bit each day. I feel that it is important to do this with the individual babies rather than the whole litter, as it forces them to rely on themselves for support, and so helps to build confidance later in life.
Sexing very young babies can be difficult if you don’t know what to look for, but once you learn how you’ll find that it’s actually very easy:
On the male, the distance between the anus and the urethra is farther than on a female. You may be able to see a small pouch of skin on a male baby (the scrotum) but it’s more obvious on some than others. The best way to judge is strictly by distance- the anus and urethra will be touching or almost touching on a female, and a little bit farther apart on a male.
If you have trouble with using that method, you can wait until the babies begin getting fur- at that point, check them for nipples- girls have them, boys don’t.
Baby rats will begin nibbling solids at around 2 weeks of age. At about 2 and a half weeks, you can offer them soft food- soft fruit, oatmeal and baby cereal in soymilk, scrambled eggs, lab blocks softened in water or soymilk, etc. At four weeks they will be fully weaned.
You should seperate the babies into male/female groups by the time they’re five weeks old. They should stay with their same-sex siblings until six weeks, and at that time can go on to new homes.
© B. Huddleston/Ratsicles Rattery