It is important to think ahead before breeding hamsters and not just jump in at the deep end. Consideration must be given to the housing and finding homes or an outlet for the babies. Your hamster can have quite a lot of babies, 15 to 20 is not unknown, although 8 to 12 is normal and when separated from mum another cage will be needed. By four weeks we recommend that the sexes are separated and this means another cage to find. If homes cannot be found quickly then at six weeks squabbles may break out and the offenders have to be segregated,so more cages are required again. By three months each hamster is likely to need its own cage.
Having thought carefully and decided that you want to go ahead, then the rewards of seeing the babies grow and their characters develop are great. The female should be a minimum of thirteen weeks old as to breed younger could lead to problems in the pregnancy. We would suggest that the first litter is taken before the female is eight months old as this to could lead to problems. The male's age is not so important as long as he is sexually mature and of a size to be able to mate.
Female hamsters will only mate when "in season" or "on heat" which is normally every fourth day, approximately between sunset and sunrise. At any other time the female is likely to turn on the male and injuries can occur if they are not separated quickly.
The procedure we follow is quite simple and has worked well for the last few years. First it is important that the hamsters are fooled into believing that it is the correct time of year for mating, this means that the lights may have to be left on for at least twelve hours a day and in winter some heating may be required.
A box 18 inches square and about 12 inches high can be used for the mating and we would suggest that a pair of gloves are worn in case the female turns on the male and you have to intervene although if you are careful they may not be necessary.
We usually try the matings from about 8.30 in the evening. Place the male and female in the box and watch the postures of both. If it is the wrong night then the female may be seen to be squatting or trying to turn the male onto his back by putting her nose under his belly. If this is the case the female should be removed and the mating tried again the next night. If the female is ready then she will normally run away for a few strides but when the male places his front paws on her back she will "freeze". This means that she will be standing quite still with her hind legs braced and her tail and ears erect, once seen it is always recognisable.
Leave them together for between 20 and 30 minutes after the male is seen to penetrate and then replace in their own cages. Normally once mating has started there should be no trouble but they should never be left alone as sometimes the male becomes over aggressive in biting the back of the female's neck or over enthusiastic about washing her ears and ending up at the wrong end. Both of these instances can be stopped by just touching the male.
The Gestation period is only sixteen days ( the shortest period known in mammals) and so care should be taken with handling and feeding after the first seven days. We have found it advisable to give the female some milk each day, either in the form of runny porridge or with bread soaked in it. A few extra sunflower seeds given from the twelfth day onwards should help with lactation (making milk). Two days before the babies are due the female's cage should be cleaned and plenty of fresh bedding supplied to make a nest. All old food should be removed and new food given.
We have found that the babies are born from 6.00 p.m. onwards on the sixteenth day with most arriving during the early hours, although some will not give birth until the next evening. If the babies have not arrived by the morning of the eighteenth day then you should consult your vet with the view to possibly inducing the birth.
Milky foods and sunflowers should still be given daily but care must be taken with the dish containing milk as the babies can be mobile from a very early age and wander into a deep dish and drown. At seven days old you may find the babies trying to drink the milk and so a shallow dish can be used, also a little solid food can be sprinkled into the nest.
If the female covers the babies every time she leaves the nest then it is advisable not to be nosey and look at the babies as she may destroy them, but should she leave the nest open then you can investigate but care must be taken not to touch the babies or upset the mother. As the babies get older some mothers will let them wander and gather food for themselves while others will haul them back to the nest and in this case it is advisable to drop some food into the nest itself as growing babies eat a lot.
At fourteen days, if you do not have a over protective mother you may be able to clean the wet corner and dispose of any old food and replace with fresh but care must be taken not to upset mum.
The babies can be split from mother from twenty-one days although some Fanciers leave them until they are twenty-eight day old. The actual time for splitting may depend on the number in the litter, the size of the babies and the mothers state of health, all of this will come with experience.
We like to split the sexes into separate cages before they are twenty-eight days old and we like to keep them together (if we are keeping a number from the litter) as long as possible as we believe they grow better. As soon as we hear a serious squabble we split the aggressive one into its own cage.
Once split from mum the babies should be handled each day to make them as friendly as possible as a quiet hamster is always easier to sell.