By Jackie Roswell and Julian Barker
First appeared in the June 2001 issue of the NGS Journal as “Bringing up Baby”.
Young gerbils are called pups after their appearance at about a week old when they look for all the world like a new born pup. Like the young of most small rodents gerbils are totally dependant on their parents for the first weeks of their lives. Gerbils make excellent parents, doing a great job of caring for their own young with the minimum of human intervention, but this article will help you know what you can do to help, what to look out for, and what you can do if things start to go wrong.
This article will not go into the details of mating gerbils etc, as it is intended to cover the care and development of gerbil pups. However, a few things relevant to the birth are noted here. It is important to remember that gestation can take a variable amount of time. This is normally 23-25 days, but if a gerbil is nursing another litter, birth of the next can be delayed to about 35 days, and possibly even as far as 43 days. This delay is important because gerbils mate the same day as giving birth, and the longer period for the second litter gives the mother time to raise one litter, and then produce another when she is ready to nurse them.
Another important thing is that gerbils rarely hurt pups, but there is an important exception. Adult females will often damage or destroy pups unless they are themselves about to give birth, or are nursing. For this reason it is not advisable to breed with any group of gerbils with more than one adult female. Males on the other hand are invariably very protective towards small gerbils of any age and can be relied upon to help keep gerbil pups warm and clean, whether they are the father or not. It is often said that male gerbils need to be separated from the pups to stop them hurting them. Nothing could be further from the truth.
Lastly, during gestation, and when nursing, make sure the female has unlimited water. Mothers drink a lot more than normal and restricting water supply can affect the size, numbers and health of her offspring.
The first you will probably know of your new litter is when you hear squeaking coming from a deep nest the mother has built. Gerbil pups can be very noisy! Especially in the first few days. A litter of gerbils will normally number between three and six pups, although larger numbers up to nine or exceptionally ten are not uncommon, as are litters of one or two. Litters of larger then seven can be a strain on the mother, and if you have another litter of a similar age it may be advisable to even up the numbers by fostering some pups from the larger litter with the smaller. Alternatively, you can offer some of the pups small pieces of bread soaked in condensed mild which they can suck on. This is safer than supplemental feeding by syringe or dropper as these can lead to flooding the lungs.
When born the pups will be small, about the length of the last joint on your smallest finger. They will be blind, hairless and their ears will be closed. Over the first week they slowly get a coat. By about ten days they are fully furred. By about two weeks of age they become very mobile, walking around very fast, despite their eyes still being closed! At about two and a half weeks they will be putting things in their mouths and chewing on them. They will pick literally anything small enough up and test it with their teeth, they also start making burrowing movements. A day or two later their eyes will open, often one at a time, a day apart! Finally, at three and a half weeks their ears will unfold and they at last look like small gerbils!
Pups can be safely handled at any age. Mothers are not usually too bothered by humans doing this, but look out for any anxious behaviour by mum or dad. If they do not appear to approve of what you are doing, remove them to somewhere else and give them something to explore or play with. Whilst they are busy you can handle the pups. The only other thing you need to be wary of is that even very young pups can be very active. They will slip out of your hands and be off very quickly. So always make sure they are held only a few inches above a soft surface in case you drop one.
Fortunately, like adults, gerbil pups suffer few illnesses, however, there are a few problems that can be much more dangerous for pups than they are for adults. The main problem for pups is respiratory illness. This seems much more common when pups are raised on cedar or strong smelling pine shavings. The aromatic oils in shavings probably cause some irritation of the linings of the respiratory system and lead to infection. The first sign of a respiratory problem is usually a pup of about three weeks of age that seems less active and has fur that is puffed up. If held to the ear the pup will make a characteristic clicking noise as it breaths. If left to its own devices such a pup will die in a few days. However, if given appropriate antibiotic treatment the illness will clear up in no time at all. If you see any sign of such illness you must consult a vet.
Another serious ailment is diarrhoea. This is usually a sign of something serious, normally an infection by Tyzzer’s disease or E. coli. Both diseases are often fatal but rehydration and antibiotics may save the gerbil. Also, if such a disease appears it is important to seek help from a vet as all your other gerbils may be at risk from these serious illnesses.
The only other health problem that normally affects young gerbils is where one of the pups seems to fail to thrive. It will be smaller than the others and may appear to not develop fur properly, possibly with a bald patch on the back. This is usually a sign that the pup is not getting enough milk. There are two possible solutions. One is to take t[he other pups away for half an hour. Put them somewhere warm, this will allow the pup a chance to catch up on its feed. A more successful approach is to supplement its feed with bead soaked in evaporated milk. The pup will suck on this and get the nutrition it is missing. You should find that despite its slow start, once a pup like this gets going it will soon catch up with its litter mates.
Of course milk problems can affect whole litters. There are two main ways this manifests itself. Firstly, some small litters, mainly ones of one or two pups, do not seem to stimulate the mother to produce enough milk. This is most common with younger mothers. These litters can also be brought up with evaporated milk, or can be fostered with other mothers. The other problem is where an elderly mother, say over two years old, seems incapable of producing much milk. The solution is the same, but obviously breeding from such a female should not be encouraged.
Even though their eyes may still be closed, baby gerbils are very active. At about two weeks of age they begin to explore their surroundings, albeit on wobbly legs! Like most young, they have an enormous capacity to get themselves into trouble! You can lessen the risks by removing deep dishes, these have the potential to trap baby gerbils who are not big enough to climb out. Baby gerbils can drown in a small bowl filled with water. You should also remove all water bowls and use a bottle. Generally, bowls generally are not a good idea as the gerbils will simply fill them up with litter from the cage. Another potential hazard for baby gerbils is bedding made up of strong fibrous material such as cotton wool, or any fabric. These can easily wind their way around a leg causing amputation, or around the baby gerbil’s neck and literally strangling it. You can also buy other types of bedding that although made from cellulose fibres, look very much like cotton wool. These should also be avoided as they are just as dangerous as other types of fibre. The best material for bedding for all gerbils is simply toilet tissue. Gerbils will shred this and fluff it up into a soft warm bed. Because the paper fibres are so short this is not dangerous.Lastly avoid wheels that have open rungs, baby gerbils and indeed adults can trap a leg or tail and be quite seriously injured. It is not necessary to provide gerbils with a wheel, they usually get plenty of exercise by burrowing. However if you do want to provide them with a wheel, buy one that is fully enclosed so that there is no possibility of trapping tails or feet.
By three weeks of age, baby gerbils are now eating solids although they will still make visits to the ‘milk bar’. They may find eating some of the larger foods, such as sunflower seeds difficult, so you can help by providing shelled seeds, although not too many, sunflower seeds have a high fat content and over indulgence can make gerbils fat. Baby gerbils love the smaller, millet seeds that are more commonly sold for pet budgies. These small seeds are just the right size for their paws.At four weeks of age, gerbils are usually fully weaned, but experience shows that they benefit from a further week of parental care. The pups can be removed any time after five weeks, and should definitely be separated from the parents, and members of the other sex, by eight weeks if unwanted pregnancies are to be avoided. If the mother has another litter, the older babies will help to care for their new, younger brothers and sisters just as the father will.
As you can see, as long as a few dangers are avoided, gerbils left to themselves will get on and bring up their own young with few problems. Very little else can go wrong, but remember that if there are any health problems you should consult your vet.