Breeding

My sheltie sow Minnie

The breeding of guinea pigs is part of a moral debate regarding ethics, responsibility, risks and reasons to do so. Many breeders, who understand the process and all risks involved, do attempt to educate those who own guinea pigs as pets on the reasons why it is ill advised. I am sure to outsiders this must seem a little hypocritical; however breeders do have very good reasons for their deterrence’s.  There are many risks involved in the breeding of guinea pigs. Breeders dedicate much of their lives to researching and understanding the health, genetics and medical aspects of their beloved cavies. They do so with view to minimising the risks to their animals, whilst breeding the highest quality healthy, guinea pigs to continue their lines and improve the breed.

My aim as a responsible and loving cavy owner is to understand as much as I can about guinea pigs, including the breeding process. One of the reasons I blog, is to share this information with others who are also keen to learn and seeking reliable information. So if you are wanting to breed, find yourself with an unplanned pregnancy or simply want to know more – this information is for you.

A female should not be bred before 4 months of age. However, a sow over this age should be physically mature enough, after reaching a weight of 500g. A sow over 12 months of age who has not delivered a litter should not be bred. The reason for this is, if the first breeding is delayed past 7 or 8 months the pubic symphisis separates less easily and fat pads obstruct the pelvic canal. This can cause dystocia and even if a caeserian section is performed, the outcome for mother and babies is typically death.

Another consideration is the roan gene which when bred in a homozygous (or double) combination can result in weak, unviable young or stillbirths. This is a fairly complex genetic occurance found in roan and dalmation breeds that I am not even going to attempt to explain at this stage of my learning process. I will simply say that it is worth researching and having a basic understanding of it, if you are considering deliberately mating guinea pigs of your own.

When arranging a mating it is easiest to simply leave the boar and sow to cohabit for several weeks. A female guinea pig comes on heat approximately every 14-18 days from the age of around 4 weeks and there are between 6 and 12 hours during this time in which she will accept the male. After sufficient time has been given for mating to occur, the mother-to-be can be returned to her usual cage mates (which should be one or more females.) When delivery day approaches, she needs to be given her own private birth suite with privacy and soft bedding.

My pregnant sow Abby

 The typical gestation period for Guinea Pigs is 65 to 70 days (an average of 68 days.) There are no obvious changes during the first four weeks. The last two to three weeks of pregnancy, the mother-to-be will become quite "plump." The babies will comprise more than half of her body weight. You can see and feel them moving.  During pregnancy she needs twice as much vitamin C to prevent toxemia. She will drink a lot of water and eat a lot of food! A pregnant sow should be supported at the front and also at her hind quarters when being lifted. She should be handled as little as possible during this time.

There are very few signs that labour is approaching. She doesnt build a nest or make any other preparations. The only real way to tell is by checking whether her pelvis is spreading. You can feel the pelvis, directly above the sow's vagina. Once this bone begins to part about a finger width or two apart, she will deliver soon. During labour it will look like she is hiccuping or bouncing.

The birth process usually takes place in the daytime and is all over in less than half an hour. The time between babies should be less than five minutes. Guinea Pigs usually have two to three babies. Although sometimes there is only one and they can have up to eight! Mothers rarely need any help with this process. She will pierce the amniotic sac with her teeth but if she doesn't do this, you may need to do it for her. After that she will clean them off and eat the placenta.
 

Fudge from 'Funky Kingdom Cavy Stud' cleans her first born pup

 The babies are precocious, which means they are ready for action. They are born with eyes open, a mouth full of teeth and will be running around the pen munching on food before you know it. However they do suckle milk from their mother for around 3 to 4 weeks. Weaning time is also goodbye time for her sons, who need to be moved into their own home as they will have no hesitation with mating with their mother and she is fertile again immediately following birth. Back to back litters are very unkind and can be dangerous. A sow should be allowed the opportunity to recover and regain condition before consideration is given to the possibility of subsequent breeding.

1 day old pup from 'Funky Kingdom Cavy Stud'

It is wise to moniter both mum and her litter closely. Weighing of the babies regularly can help clue you in to any that are experiencing failure to thrive. They may need more time to suckle at the breast or in extreme cases supplementing (ie. hand raising.) It is okay to handle the young but care must be given to do so safely as they are typically very wiggly and excitable.

If you want to read more about breeding I suggest taking a look at Emma's blogspot 'All Things Guinea Pig' the link to her breeding information page is here. Emma is the proud owner of Sirocco Cavy Stud and possesses a wealth of knowledge when it comes to Guinea Pigs.