INTRODUCTION

The crossing of two animals to have a litter is a very serious matter and one that needs a lot of thought before it is done. It is not enough just to put a male and a female together and wait for everything to happen, but it is necessary to study beforehand, as well as to consult professionals (ethical breeders and veterinarians) so that they can inform us about the procedures, whether our pets are suitable for breeding or for that particular crossbreeding (lethal genes, too advanced age, serious physical faults? ); there are many people who are excited about having a litter or who do it on a whim for their children and then find that it is very complicated or problems arise that end in the worst possible way.

We will now explain why we should NOT breed our hamsters and why we should leave it to specialist breeders.

PROBLEMS ASSOCIATED WITH GESTATION OR BIRTH

VAGINAL BLEEDING

It can happen during pregnancy or at the due date; vaginal bleeding is alarming and should not be taken lightly.

The causes can be varied: blows, miscarriages, Russian-campbell hybridisations, excessively young mother, too large offspring that are impossible to expel (two hours or more of labour), pyometra (uterine infections)...

If we see blood in the vaginal area of our pregnant hamster, we have to run to the exotic vet, as this small gesture can be the difference between her living and dying.

SPONTANEOUS ABORTIONS

Spontaneous abortions occur when the pregnancy is interrupted without any apparent cause, and the severity of the miscarriage depends on how long the hamster has been pregnant.

Before 8 days of gestation these miscarriages are practically impossible to notice, being known as ‘reabsorption’ (the mother's body will absorb the foetuses and make them disappear without any trauma) or, in the case of expelling them, she will eat all the remains and it is possible that we will not notice them either (apart from the fact that our hamster does not put on weight).

If the abortion happens after the eighth day of gestation it is possible that the abortion will have dire consequences, if we see her giving birth to dead babies it is important that we go to the exotic veterinarian as it is possible that remains of foetuses or placenta inside the womb and this, in the long run, will cause a pyometra (infection of the uterus), septicaemia and death.

REABSORPTION OF FOETUSES

Known as ‘silent abortion’, fetal resorption occurs when the pregnancy is not viable and the body, knowing (or believing) this, absorbs the foetus into the bloodstream without leaving a trace.

Some of the causes that can lead to this are that the female is too young or too old to be a mother, that she has feeding problems (little or low quality food), dehydration, stress, uterine malformations, lethal genes associated with the colours or colour patterns or toxics (very aggressive veterinary treatments, deworming...).

This is not frequent and we will notice it because our hamster's belly does not grow or harden, just as there are no traces of blood in the cage.

PREMATURE BIRTH

Normal hamster births can happen as early as two days before the due date, but if they happen earlier, this is known as ‘premature birth’.

There is no exact reason for an early delivery, but in many cases it has to do with some kind of hormonal problem (very high oxytocin levels); the offspring born prematurely are usually very small and weak, and are often stillborn or malformed. It is possible that some of the premature offspring survived thanks to the mother's help (we have our hands tied) but the quality of life of these hamsters in the future is a mystery and physical sequelae are common.

LATE DELIVERY

In the same way that we can find that our hamster suffers a premature birth, it can also happen what we know as ‘late birth’; in this type of births the cause of this is usually that the levels of oxytocin in the female were too low (‘oxytocin’ is the hormone that causes and facilitates the birth), so the body ‘does not know’ when those pups should be born or, also, it can happen in very small litters (they do not hit the base of the pelvis and, therefore, do not help to release that hormone).

These cases are very dangerous, as there are only two options: the body expels them (dead) after a few days or the offspring mummify in the uterus, becoming a potential source of infection.

PSYCHOLOGICAL PREGNANCY

Sometimes ‘non-existent’ pregnancies occur in sterile females that have recently mated or are in the fertile period in close contact with a male without the possibility of interbreeding, all as a result of hormonal imbalance.

It is characterised by the female acting as if she is pregnant, often gaining weight and making nests, and even being able to produce breast milk; they never give birth and never put on as much weight as in a real pregnancy.

This is not completely harmful, but it is good to be aware of what it is in case we find ourselves in this situation, castration would be a way to avoid or nip this behaviour in the bud, although it is a risky procedure.

IGNORANT’ MOTHER

In the first days of growth babies are extremely dependent on their mother, they cannot digest or excrete on their own, as well as sometimes forgetting to breathe, they need feeding every two hours and the warmth provided by their mother, as they cannot maintain it. The mother is very busy providing all this and infrequently leaves the nest, usually to eat, relieve herself and sometimes for a bit of exercise. However, these ‘escapades’ do not usually last long.

Hamsters are very responsible with their babies until they are mature, but there are times when the mother is disinterested in her young and chooses not to care for them. This usually happens because she does not feel a sense of belonging to her litter, which happens if we touch the babies, stress the mother by constantly watching or holding her, or impregnate the nest with a strange smell (this happens when we clean the cage or apply deodorants, perfumes or similar substances near the nest).

This is why it is important not to touch the babies (or the mother if possible) or clean the cage until after the babies are 15 days old. We have to ‘remind’ the mother that she has a nest to look after if we bring her (with a glove) close to her babies, she may recognise them and decide to continue looking after them, or she may ignore them completely. If your female chooses not to care for the babies there is the possibility of caring for them yourself, to find out how click here.

It is important to be aware of this, as babies do not survive more than two hours without their mother.

INFANT FEVER

This happens very rarely, because the mother's milk contains infections that cause swelling in the baby's abdomen, resulting in death. This can be solved if the bitch is treated with antibiotics by a veterinary doctor.

Sometimes babies are constipated or may be born with genetic problems that prevent them from having developed digestive or excretory systems, so they cannot digest/excrete their waste. Not to be confused with infant fever, in constipation the abdomen is hard, whereas in infection it will be soft.

COOLING OF BABIES

As mentioned above, babies are dependent on the mother's warmth. It often happens that when the mother leaves the nest to relieve herself, she drags a suckling baby with her, or when they are learning to move they escape from the nest.

When alone, their body temperature drops, causing lethargy and hypothermia. This causes death if the young is not returned to the nest as soon as possible. If it is still alive, it can be resuscitated by the mother.

It is usually the mother herself who goes in search of her young, either because she realises that a baby is missing from the nest, or because it calls out to her with its whimpering. If some time passes and the mother does not come to her aid, we must put it back (always using gloves).

CANNIBALISM

Cannibalism in hamsters happens due to certain factors that cause it to happen but, like everything else, they are avoidable.

One of the causes of a mother hamster eating one or more offspring is that her diet is poor or inadequate, especially in terms of protein; then, unable to produce enough milk for everyone, she decides to eat the weakest offspring of the litter in order to fill her stomach and produce the milk necessary to feed the others.

Another option is that the mother is too young (under the minimum age indicated for her species) and inexperienced so, seeing that these dead young are a ‘danger’ to the nest (a source of infection and an ‘alarm’ signal for predators), she devours them.

To this, we have to add a stress factor; it is very important not to disturb the mother or the nest (this is very important if we have children at home, who will be very excited), if the hamster hatchlings acquire a ‘strange’ smell (different to that of their mother or nest) the female will consider it a potential intruder and will attack, possibly destroying the whole litter. If we have to touch or handle the litter, we should always wear gloves and put it in a clean container in which we have not used disinfectants with perfumes or strong smells; it is best to wait (if we do not have experience) until they are 10-15 days old to handle them.

On the other hand (and this is what can bother us most) is that there are females with the ‘vice’ of cannibalism implanted in their brain; despite having a good amount of food at their disposal (healthy and complete), tranquillity and correct handling. They do it without apparent cause and this is very frustrating. If we have a ‘cannibalistic’ female and this behaviour is repeated in two consecutive births, the best thing to do is to dispense with this female in our breeding programme and look for an adoptive home for her.

DEATH OF OFFSPRING

This is quite common in litters that are too numerous, born to very young or old dams or the result of too ‘strong’ or not properly studied incest (‘linebreeding’ or ‘inbreeding’); as a result of all this, weak, deformed animals or carriers of lethal genes due to an incorrect crossbreeding may arise. These animals usually die at birth or in the first few days and the mother takes care of their ‘disappearance’ (we have seen this in the section ‘cannibalism’) but, if this does not happen, it is our obligation to remove the carcass or any pieces of carcasses that may be present; if we do not do this, it is quite likely that they will become a source of infection and cause their siblings to become ill or be abandoned by the mother.

DEATH OF THE MOTHER

Sometimes the mother's good health and proper care from all points of view is not a guarantee that misfortune will not occur (although it does greatly reduce it). Sometimes we lose the mother and the chances of the offspring surviving are always proportional to the age at which she was lost; it is not the same for a bitch to die at birth or in the first twenty-four hours as it is for a bitch to die within a week. We can try to bring the litter forward by means of artificial milk, something very complex and exhausting but which can help to bring some babies forward (it is not certain that all of them will come out, even with years of experience).

Most people would think of looking for an adoptive mother for them, as is done with dogs, cats or even rabbits, but this is impossible with hamsters, as the mother would reject them immediately or could kill them.

ACCIDENTS

Accidents are one of the most avoidable things when we have a litter of hamsters but, at the same time, they are one of the most common things in the case of inexperienced owners or those who are not at all interested in the welfare of the litter. Falls from great heights (cages with floors), drowning, escape or heart attacks when trapped (cages with barred walls) or diseases associated with an inadequate substrate are the most common ‘accidents’.

Undoubtedly, this is the easiest cause of death to prevent, but it depends only on the interest and prior information of the owner of the litter (since being a ‘breeder’ is very different).

MOTHER ATTACKS OFFSPRING

Although hamster mothers are usually devoted and very protective of their offspring, cases of aggression towards their own offspring are not uncommon. The most common cause of these attacks is the hamster's natural territoriality and stress, which can be triggered by too many litters (‘too little’ space in the cage) or, in the case of mothers who no longer want to suckle their young and want to be left alone, resorting to aggression to achieve this end.

If we encounter this case in any of our litters, the best and most rational thing to do is to keep calm and separate the pups from the mother, proceeding to finish rearing them ourselves.

DOUBLE PREGNANCY

If we do not separate the male from the bitch before the birth, he will mount her as soon as she gives birth and will almost certainly impregnate her again. If this happens, the situation becomes more complicated, as the female will have to have a lot of food and protein at her disposal to be able to raise her litter and gestate the next one (otherwise, she will end up malnourished and may abort), being quite likely to reject the first one due to the physical and mental stress to which she would be subjected.

After this situation, it is best that the bitch does not breed for a good season or not at all, in order for her to recover physically.

After this situation, it is best that the bitch does not breed for a good season or not at all, in order for her to recover physically.

INTERNAL HAEMORRHAGES

Internal haemorrhages (during or after birth) are one of the things we have to take into account if we want to breed our hamster. This has nothing to do with whether the female is well or poorly cared for, it is a possibility that is there, a lottery.

Internal bleeding occurs when an artery or vein ruptures and blood starts to flow, either out through the vagina or stays inside the body, engorging the organs. If this happens, it is very unlikely that our hamster will be saved, so it is important to keep an eye on it as closely as possible and check it without causing it stress. If we notice that it is bleeding too much or does not stop, we must go to the vet, however small the chances of survival may be.

DISTOCIA

What is ‘dystocia’? In medicine, the term ‘dystocia’ is used when the delivery or expulsion proceeds in an abnormal or difficult way. It can be the result of uncoordinated uterine contractions, an abnormal position of the foetus, a relative or absolute cephalopelvic disproportion (the pups have too big a head and the mother's pelvis is too narrow) or abnormalities affecting the soft birth canal. In hamsters, obesity is also one of the causes of this disease, the symptoms of which are lethargy in the mother, vaginal haemorrhages, very long expulsion processes without the foetus coming out and symptoms of suffering in the mother. If we observe this in our hamster, it is essential to go to the vet as a matter of urgency.

HAMSTERS THAT DIE DURING BIRTH

Sometimes it is unfortunate that the mother dies while giving birth, for various reasons. The survival rate of babies is directly proportional to the number of days they are alive at the time of losing their mother. Artificial breeding of hamsters is possible, but it is exhausting and does not guarantee 100% survival. There is a post dedicated to that, which was pointed out earlier in this post.

It should be noted that female hamsters do NOT accept foreign babies, so looking for a wet nurse is not a solution.

DO YOU WANT TO BE A BREEDER?

If even with all these warnings your greatest desire is to dedicate yourself to the breeding, selection and improvement of hamsters, it is important to remember that it is something for which you have to study, and we are not referring to courses or specialized careers, but to read many books, articles and national and foreign websites in order to have as much knowledge as possible. Being a veterinary assistant is a great help to know how to distinguish what is wrong with our hamster or when a situation requires veterinary assistance (and when it is not necessary), we will have to be members of a national or international club that will help us in the correct selection, import healthy specimens of good quality (which is an important investment in the transport issue), adapt our house or acquire a place where we can have correct facilities and be able to separate the offspring until they have a good home, etc.

It is something that is done out of passion and that never makes anyone rich, on the contrary, it costs a lot of money and a lot is invested in keeping the animals well and doing things well, as well as investing a lot of free time and nights that could be spent sleeping, going on holiday or partying. 

CONCLUSION

Breeding any kind of animal is a very serious business that should not be taken lightly. Many unfortunate things can happen because we are dealing with living beings and, in the case of hamsters, we have the disadvantage that when they reach weaning age (a very, very short period after birth compared to other animal species) we will have to have a habitat prepared for each hamster, so we have to have a good space and a predisposition to have it. 

Ethical breeding is never driven by money (which is used to cover the expenses of the animals and their parents), but by passion, quality and affection.