In comparison to most mammals, gerbil babies spend a very short time in their mother’s womb. The time averages 24 days but the American Gerbil Society notes that it can be as long as 28 days. However, this is the normal gestation period gestation period for female gerbils over three months old.
Female gerbils that are still nursing from their mothers can delay being mothers themselves, even though they have mated. Their bodies delay planting the fertilized embryos in the womb until the gerbil has physically grown a little. So, the absolute longest a female gerbil can go from mating to birth is 43 days.
Since the average size of a litter is four and gerbils can produce up to twelve litters a year, carefully consider if you want to let your pet gerbils breed. Within a matter of a few months, you could have more gerbils than you know what to do with.
Care of the Pregnant Gerbil
Ideally, the male and female should be left in the tank together. Male gerbils help in caring for the young and protect them against invaders as best as he can. But if there are other female gerbils in there, please remove them or the pregnant gerbil may pick a fight with them.
Pregnant gerbils keep their slim figures for quite a while into pregnancy. Some may begin to show as early as the 18th day, but often they will not show until the 21st day. She will then transform into a furry pear. Try not to handle her after the 18th day as rough handling may lead to a premature birth or may cause the pregnant gerbil a lot of unnecessary discomfort.
Gerbil breeders recommend feeding the pregnant female a little extra protein in her diet. This can be anything from scrambled eggs to unsalted peanuts. This should only be a few extra mouthfuls or a 15% increase in her diet.
Birth
Gerbils make a fluffy nest of fibrous material and their bedding. A pregnant gerbil will most likely decide to make a nest under a good hiding spot. Although it will be tempting to keep checking on her, try to leave her alone as much as possible. Keep the noises down in the room where she is in and keep a lot of strange people from bothering her.
Because the gerbil’s gestation is so short, they are not very well developed when born. Gerbil babies (often called pups) are tiny, hairless, blind and deaf. Don’t be surprised to see the mother gerbil harassing the father up to 48 hours after birth. If the harassment is severe, you should place the male in another tank until the female settles down. Do your best not to disturb anything in the birthing tank for five days.
Gerbil pups grow incredibly fast and begin to have a good coat of fuzz by the time they are a week old. They will be able to see, hear and reasonably move about by day 20. By six weeks of age, they are ready to be weaned.
Sources
Fox, Sue. Gerbils. T.F.H. Publications; 2007.
American Gerbil Society. Gerbil Care Handbook.
Pet Place. “Gerbil Care.”