A Closer Look At Pairs (Boars - Sows - Mixed)


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Mar 10, 2009
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This guide is an article series that I have written for Guinea Pig Magazine issues 50-52 (May/July/September 2019).
It is the propriety of GPM and is being shared on here with the magazine's permission.

1 Introduction
2 Sexing Guinea pigs: Where to look and feel yourself
3 Boar Pairs
4 Sows Pairs
5 Mixed Pairs
6 Conclusion

1 Introduction

Pairs make up the vast majority of how guinea pigs are kept as pets.

Unfortunately, our wide-spread assumption of a pair of guinea pigs of being as cuddly and close with each other is as unrealistic as our idea of guinea pigs as instant cuddly animated toys. Being a social species doesn’t mean that it is as easy as sticking another guinea pig into a cage for happiness (Big No No!). Like humans, guinea pigs are people and react as individual personalities. And like humans, they have firm likes and dislikes as to who they gel with!
In the following I am taking a closer look at what makes boars, sows and mixed pairs work; what makes each combination special and what are the specific challenges as they go through life.

Minx and Mischief - best of girlfriends

It can of course only ever be a gross generalisation, considering how complex and varied guinea pig personalities are, which makes each bond unique and different. When it comes to guinea pigs, for every rule there are at least ten exceptions – and you will never cease to be surprised!
However, there are certain aspects that come up again and again and that are worth considering when you want to start out with guinea pigs or want to add more guinea pigs to your home or find a new friend for a bereaved or fallen-out piggy of yours.

My badly pining first own piggy Strolch 'Rascal' with his new second 'emergency' wife Böhnchen 'Beanie'

There is no totally problem-free combination, and whether you want to opt for boars, sows or a mixed pair with at least one de-sexed partner is ultimately due to your personal preference, the availability of neutered boars or spayed sows and rescue access – or simply the piggy you fall in love with.

My first childhood guinea pigs were boys but when I fell in love with a large pair of very speaking eyes again as an adult, they belonged to a pet shop sow (who promptly presented me with some unplanned offspring right in the middle of a major family crisis!), and everything has followed on from that…

Minx with her companion Mischief (thankfully a sow, but it took two vet trips to verify!) and her two unplanned baby daughters


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Mar 10, 2009
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2 Sexing Guinea Pigs: Where to look and feel yourself

With the steep rise of guinea pig sales worldwide, the problem of mis-sexing has become a real and increasing headache in recent years.
So many large hoarder intakes that are pushing rescues all over the world to their limits have started with a mis-sexed shop or breeder pair. Welfare or rescues are all too often not involved until the number reaches 80, 150 or over 300 guinea pigs several generations down the line. Typically there are usually a lot more guinea pigs than estimated and nearly all the sows are pregnant, so numbers more than double in rescue… And all of these guinea pigs have to be fed, cared for, medicated and in time found homes that comply with welfare standards and the required commitment to continuing good care.
The need to double-check the gender upon arrival and before you put any guinea pigs together is paramount!

With the following tips I want to show you how you can easily double-check the gender at home without having to rely on the judgment of people who should know better but often don’t, or whose knowledge and experience you generally have no idea about when asking for help online. When it comes to sexing, guessing games by shop personnel, vets with little experience of guinea pigs, ‘experienced owners’ or online posters are simply not good enough!


Apart from the often confusing and anything but textbook clear array of the genitals, there are two areas where the gender is unmistakeable.

Textbook pictures
Here are some textbook pictures, but there is in reality a wide variation; especially babies can be anything but clear. That is the reason why we are pushing the hands-on part of the sexing process and aim to teach how you can learn to reliably sex your piggies yourself without ever being at the mercy of other people whose experience you often don't know ever again!

Textbook boar with large fully descended testicles

Same boar 2 weeks after his neutering operation; this is also how baby boars with not yet descended testicles look

Textbook adult sow

The hands-on sexing check
These are the areas you need to look and feel for.
If possible, please ask another person to hold the guinea pig and angle the genitalia so that they are well lit. You can then switches rolls and compare your findings.
If you have already got safely sexed guinea pigs, have a close look at them first so you have got a known basis to work from.

  • The presence or absence of a penis ridge under the skin
    Now feel just above the knob on the belly side (see arrow in th picture above).
    - Boars have a tiny penis sheath just under the skin.
    - Sows are totally flat and soft in this area and you can’t feel any tiny hard lump.

  • The inside of the slit
    Firstly gently pry apart the slit.
    - In boars it is a straight opening that goes simply down into the anal sac.

    - Sows have a fleshy arrangement of side-flaps just below the rim that seals the opening unless they are in season and ready for mating.

  • If both areas come back with the same answer, you can be 100% sure that you have got the gender correctly, irrespective of the arrangement of the genitalia, whether you are able or unable to express a penis (often not quite as easy for new owners) and whether a boar has got descended testicles or not. Male babies under 4 months and neutered boars won’t present with testicles.

Please also note that all guinea pigs have two nipples and that there is no gender difference in their appearance.

Recommended illustrated online sexing guides with pictures of varying ages (including babies) and featuring both outside and slit reference pictures:
Illustrated Sexing Guide
Boar Care: Bits, Bums & Baths


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Mar 10, 2009
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3 Boar Pairs

When you ask boar owners, they will tell you that boars beat sows paws down any day and that they would not exchange their boys for any gold in the world!
Yet boars have sadly such a bad press and are victim of so many long debunked but deep-rooted myths. It is not the boars’ fault, but the fact that the vast majority of them are bought at shops or breeders for their looks and not whether they are best mates hanging out together in the shop pen, and they are persistently failed at all levels by ignorance and the unwillingness to respect their own species needs.

Common misconceptions
  • Myth: Boars can only be kept as singles because they fight.
    Fact: Noticeably more boar pairs than not make it to adulthood without fall-outs. And you can influence that percentage in your favour to some extent.

  • Myth: Brothers won’t fight and fall out.
    Fact: Whether boars fight or not depends on their personality and outlook. If you have two dominant brothers, then they will clash just the same as unrelated boars.

  • Myth: Only babies can be bonded; adult boars are unbondable.
    Fact: Our magazine rescue adverts and stories as well as our forum threads tell very much a different story if you need any proof! When boar dating at a good rescue that offers this service, it takes on average 1-3 candidates to find ‘Mr Right’ for any boar combination of any age, but most boars can find a new friend. Of course, the most difficult age to re-bond boars is the age they most often fall out with each other – around 6 months of age. That is why more and more rescues have started to neuter single teenage boars to help them find a new home.

  • Myth: Neutering/De-sexing boars will calm them down.
    Fact: Unless your boys have been neutered as babies (a practice, which is mostly restricted to German speaking countries and not much known outside), neutering will only affect the ability to make babies.
    It WON’T change their personality, social interaction and it will not even curb the testosterone output all that much. A dominant boar is still a dominant boar with or without his ‘treasure chest’!
    Both Nye and Llelo who I had neutered myself still went through all the typical teenage stages.
Dylan and his little sidekick Llelo - their relationship sadly didn't survive teenage when Dylan was unable to cope with a confident teenager refusing abject submission.

The tricky teenage months
While boar babies start making babies themselves as soon as they reach waning age, i.e. from 3 weeks onward, their testicles won’t descend until around 3-4 months. This is the time when they gain sexual majority (which only refers to the full development of the sexual organs) and when testosterone production sets in often very dramatically.
Unfortunately, veterinary textbooks usually only cite sexual majority but not the much younger age in which boars start to make babies. Especially general vets without experience with guinea pigs won’t be necessarily aware that the two do not happen at the same time.

Typical problem times characterised by massive hormone spikes or highs during the teenage months are around 4 months once the testicles start descending and then the all-time testosterone high around 6 months of age when the testicles have fully descended and the testosterone is literally singing through the body. These are the two ages when not well matched pairs really clash and the most fall-outs happen.
Around 8-10 months is a period when teenagers in typical fashion try to push the limits and are a constant pain in the neck. It is a nerve-wracking time but thankfully one where fall-outs and fights are comparatively rare.
It can happen occasionally that boar pairs that have sailed through their teenage months seemingly unaffected suddenly get into big trouble after passing the year mark.

The hormonally much more settled adulthood is reached at around 15 months of age.
Adults, especially younger boars of 1-3 years old can sometimes still suffer a short testosterone spike (even the odd neutered boar, as I know from my own) but they usually last only a day or two and – with a temporary divider in the cage – don’t usually lead to fall-outs. Re-introduce again on neutral ground once the boys have settled down. Most will go back together as if nothing has happened.

The ‘Golden Boar Age’
Where boars really come into their own is as adults and especially oldies after ca. 12-15 months of age. As the testosterone output gradually reduces and after 4 years eventually fizzles out, boars mellow A LOT.
They are more often cuddly sofa companions or lap warmers than sows and often turn into real softies in old age. Of course, you also get the other ones; but even the biggest bullies can turn into really nice chaps in their dotage…
Adult boar pairs are generally as stable as sows, and older boars much easier to bond/re-bond than old sows. They are also usually much more sociable!

Happy-go-lucky Nye and his skittish best friend Nosgan - the ideal yin-yang complementary boar pair!

Minimising the risk of problems
  • Adopt a fully quarantined and carefully bonded pair of boars from a good welfare standard rescue that really cares about their pairs being personality matched and stably bonded so you can neatly avoid all the pitfalls that can await unwary buyers. You also have the rescue to fall back on if your boys get into trouble for some reason.
    While there are of course a quite a few more good rescues, all our advertising rescues operate to a good standard and we can vouch that you are in safe and knowledgeable hands with them. The majority also offers dating at the rescue for any single or bereaved guinea pigs of any age.
    Our forum rescue locator with vetted rescues: Rescue Locator (link to rescues in some othe countries below UK map)

  • Mutual liking is more important than looks – at any age!
    If you do not have a rescue within your reach and can only get pet shop piggies, try to observe them for a while before you buy.
    Choose the ones that snuggle up or hang out together most closely. They are most likely friends and your best bet of finding a stable pair without knowing their personalities.

  • Space, space, space and more space! Boars simply can’t have enough space!
    Most fights happen because a boar has been cornered or because the under-boar cannot remove himself from the territory in a confined cage set-up as he would normally.

  • Everything in twos!
    Provide only huts and tunnels with at least two exits. Children’s stools that are also open to all sides are also ideal for a boar cage. Anything that no boar can be trapped in!
    Have two of everything at a good distance from the other item: huts, tunnels, bowls, water bottles and access to hay that cannot be blocked. Ideally you have hay in two different places.

  • Having a divider or a spare cage at hand!
    Ordering or getting hold of some extra grids and connectors to be able to split your cage (C&C or traditional) can come in extremely handy, as I know from my own teenage boars.

  • Scent marking any new territory (new cage or extension).
    When introducing or adding any new territory, please wipe it down with some scent marked bedding and use old or already scent marked fleece/bedding to furnish it (including uncleaned furniture) to prevent a new hierarchy sort-out, which is one of the few occasions when an adult pair can get into trouble and at the worst fall out. If necessary use the bedding from the carrier you have brought your boys home in before transferring them or have them sitting on their future bedding first for scent marking.
    If at all possible, enlarge the territory before your boys turn into teenagers, not while their bond is already under major stress; it can be just that extra spark that lights the fuse!

Boar pairs in a nutshell
Pros: Boars are often more care-free, upfront and cuddly, especially the older they get. Boars work best in pairs.
Cons: Getting boars through the teenage hormones.

Forum boar guides with more detailed information on various aspects:
A Comprehensive Guide to Guinea Pig Boars
Boars: Teenage, Bullying, Fighting, Fall-outs And What Next?
Neutered / De-sexed Boars And Neutering Operations: Myths, Facts and Post-op Care
Boar Care: Bits, Bums & Baths

For more information on boars (including teenagers, dominance, neutering and care), you can find our big boar special in Guinea Pig Magazine issue 36 from January/February 2017. The issue can be back-ordered!


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Mar 10, 2009
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4 Sow pairs

Sows are a law onto themselves when it comes to complex characters. The longer and the more I have them, the more I cherish my boys! Soap operas hold nothing against cavy dramas! You get the whole breadth of personalities you can find in any neighbourhood, and if you allow them to flourish and express themselves, boredom is not something you’ll suffer!

Half-sisters Hedydd and Heulwen - best friends for a long life

Squabbling and eventually falling out sisters Llawen and Hapus

Common misconceptions
  • Myth: Sows don’t fight and don’t fall out.
    Fact: While full-on fights with sows are rare, they have generally a much larger social tool box to interact with each other and their behaviour is much more nuanced and often a lot sneakier. Seeing a sow with a mouthful of hair is the female equivalent of a full-on deep bite to the rump in boars.
    Sows can also decide from one moment to another that another piggy is no longer part of their group – even if that is a sister they have been together with for years.

  • Myth: Sisters don’t squabble and fall out.
    Fact: I must have got my sister pairs from the wrong places… Because in my own experience there can be no fiercer competition than between teenage sisters although they can become very attached once they adults. Other pairs maintain an ‘one against the other and us against the world’ attitude throughout their life.
    Mother and daughter pairs are generally more peaceful as the hierarchy is a lot clearer and not contested. Exceptions prove the rule!
    However, unrelated sows of different ages can be often better friends than related piggies, especially when they have been allowed to choose who they want to be with.

  • Myth: Sows have a menopause – Dead Wrong!
    Like boars, sows never lose the ability to procreate, whatever the age. Boars and sows basically start as soon as they are weaned (boars around 3 weeks, sows have their first season from 4 weeks onwards). The earliest documented sibling pregnancy is 24 days. The older a sow and boar, the higher the risk of miscarriages and fatal birthing complications considering that pups are a multiple in size and weight compared to human babies.
Closely bonded: Cerian and Breila

Feeling like family: Unrelated Nerys and Nesta (the latter of which I adopted sight unseen).
Nerys was the only piggy Nesta was ever happy with.

Unplanned babies
Sadly, mis-sexing and not separating male babies early enough are still happening far too often.
The safest place to avoid this problem is a good standard rescue with a mandatory pregnancy watch for any incoming sows before they can be put up for adoption to make sure that there are no unpleasant surprises.
The resulting learning curve or mess if there is none is not for the faint-hearted and can become rather expensive. Sexing upon arrival can take care of mis-sexed pairs, but it cannot catch any pregnancies that have happened before that point.

The Guinea Pig Forum offers ongoing support and comprehensive practical information for anybody with unplanned pregnancies and willing to stop with the breeding cycle. The specially monitored pregnancy and baby care section is only accessible after new members have signed up to the explicit non-breeding forum policy.
Other good standard forums are Guinea Pig Cages or Cavy Spirit.

If you are in that situation and can’t keep all pups, please try to contact a good rescue with quarantine, adoption checks and a policy to not rehome guinea pigs as singles. Do not offer them as free to a good home on the free-ads or take them back to the shop or breeder you have got your guinea pigs from.

Please open a thread in our strictly no breeding Pregnancy and Baby Care section for ongoing support and information.
The section is only visible to members that have accepted our very clear no breeding rules during the registering process.

The same goes for our comprehensive pregnancy and baby care information.
Pregnancy, Mother & Baby Care Guides

Pet-shop pregnant mother Blossom on the right with her sister Buttercup and her three boar pups

Ovarian cysts and hormones
Since the hormone output never stops or lowers since sows are basically not engineered to live to a ripe old age, ovarian cysts are result of pet sows generally living to a good age; they are present in many older sows. Thankfully the majority of cysts go unnoticed and never cause any visible symptoms or problems.

Sudden aggression and sows behaving like they are constantly in season are often the first signs of an active cyst. Crusty nipples and hair loss on the sides of the belly are physical symptoms as can be the swellings from large fluid filled cysts that need draining or removing.
Any bleeding from genitalia is a serious sign of trouble in the reproductive tract and should be vet checked. Sows do not bleed when they are in season. Hard/tumorous ovarian cysts need operative removing, as do any problems with the womb.

With hormonal fluid filled cysts you generally have the option between a spaying operation, much less invasive hormone treatment (chorulon injections in the UK and generally hormone implants in the US), which is unfortunately about as expensive as an operation or draining of large fluid filled cysts. The last is not permanent, but it is non-invasive and does not require an general anaesthetic. For this reason, it is much cheaper and suitable also for frail older sows. The drainage generally lasts for a few months.

Preventative spaying is a measure that several rescues have already adopted as their policy, especially those which have access to a vet who is comfortable with this operation.
However the cost of spaying operation and the fact that it is a more invasive procedure that comes with a higher rate of fatality and complications still outbalance the benefits. I do hope that as medical science progresses, spaying as a routine procedure may be a reality in times to come – but it will certainly come at a higher price for spayed sows.

Dominant mother Hyfryd and timid daughter Hirael

Like mother, like daughter: Gentle, competent and loving Taffy and Telyn

Cantankerous old age
The continuous hormone output can also mean that sows are not as accepting of new company when they are older and past the ideal pup bearing age. In fact, pairing up bereaved old ladies can be quite tricky.
I still remember the several months in 2017 I had four single widows, none of which would go with any of the others. Tegan and Calli tooke the better part of that year before consenting to live together; Ffwlbri finally moved in with her sister Tesni and her young’ husboar’ Gethin on my third attempt (they are still together with Ffwlbri now 8 years old). Nesta found happiness with having ‘Mr. Grumpy’ Nosgan next door – a boar that did come as close to her in look and outlook as I could, but it still wasn’t enough to get her to share her territory with him! Persistence can get you somewhere but nobody has said that it will be easy!
Thankfully there are also some sweet-natured gentle old ladies around…

Widows Hafren and Tegan have hitched up together because having company is better than none!

Next door company when sharing space failed: Widowed Nesta and Nosgan

Sow pairs in a nutshell
Pros: Sows are much less likely to fall out and the vast majority will get on well.
Cons: Sows are often more complex personalities, especially the older they get. Unplanned pregnancies can be an early risk while ovarian cysts can be a very disruptive factor in adult sows.

More information on sows:
Sows: Behaviour and female health problems (including ovarian cysts)
When Sows Experience A Strong Season (videos)
Moody guinea pigs: Depression, Bullying, Aggression, Stress, Fear and Antisocial Behaviour
Bonds In Trouble

You can find more information on ovarian cysts in our cyst special in Guinea Pig Magazine issue 23, November/December 2014.
The issue can be back-ordered!


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Mar 10, 2009
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5 Mixed Gender Pairs

Cross gender pairs where one party is de-sexed to prevent any offspring are by far the most stable of bonds. Fall-outs are very rare.
It doesn’t matter whether it is the boar that has been neutered or the sow that is spayed, or both. Since boar neutering is much more common, it is generally neutered boars that you will come across. In fact, there are no rescues with a spaying policy in the UK or in Australia but you can find several in the US, in Canada and as well as the only dedicated guinea pig rescue in New Zealand, which has a strict neutering policy for all their guinea pigs.
A growing number of rescues have either a strict boar neutering policy or will neuter any boars that arrive in rescues as singles and that they struggle to bond with other boars, often as part of their dating service.

5 years old Tesni has fallen head over heels for 5 months old 'toy boy' Gethin in 2016

Common misconceptions
  • Myth: All boars are accepted by any sows.
    Fact: Mutual liking and character compatibility is key. Not all guinea pigs click with each other automatically. If at all possible, date your single guinea pigs at a good rescue to allow them to have their say, especially if you have an adult or older sow!

  • Myth: Mixed gender pairs don’t fight.
    Fact: If a bonding goes haywire and a sow will not accept a rampart boar or the wrong signals are exchanged, then tensions can build up very quickly and there can be rarely a fight with bloody bites from a hard- pressed sow.
    Never leave bonding piggies unsupervised until you are absolutely sure that they are relaxed and comfortable with each other. If tensions remain, rather separate than push the issue.

  • Myth: Cross gender pairs never fall out.
    Fact: Not quite true; but later fall-outs are generally due to a medical separation or ovarian cyst trouble. Bullying by a very dominant partner paired with a guinea pig that cannot stand up for itself can in happen if the personality balance is not ideal. It can happen in either direction. However, these cases are very rare!

Llewelyn being an attentive 'husboar' to his wife in season, Dizzy

Acceptance – the big hurdle at the start
It is the sows that choose which boar they want to associate with and that call the shots when it comes to mating, not the boars.
While young sows are generally very accepting of boars, sows past ideal pup bearing age are less so. It also very much depends on whether you are trying to bond two dominant piggies or not. Some bereaved sows that lived with the same companion since a very young age can be rather fearful when meeting other guinea pigs and compensate with overly assertive.

Insecure sows can react with fear-aggression to a boar, and a dominant boar may not deal well with a rejection. If a meeting descends very quickly into mutual teeth chattering, a sow may make up her mind there and then that she won’t like him – and she is not likely to change her mind!

Alan had to sit heavily on his nether regions while wooing fear-aggressive Brathlys in lots of sessions (lasting just as long as she could stand) - but unlike many boars, he eventually won through! They are a similarly aged pair.

Failed bonding: Older lady Mererid and Dylan ultimately didn't gel as a pair after some initial interest

Bonding mayhem and big seasons
Cross gender bonding can be VERY lively and extremely smelly because neutered boars can still produce an enormous quantity of testosterone laden urine, which they spray deliberately everywhere, but mostly on the sow. In return, the sows will target pee at boars sniffing too much at the bottom to assess from the pheromones how close a sow is in her oestrus cycle to coming into season. Ideally you conduct any bonding at home in a place you can air and easily wipe down! A run on the lawn in suitable weather is also perfect.

Sows can also come into season spontaneously in the presence of boar pheromones, which can make a bonding rather mad and very vocal!
Boars can in turn lose touch with their brain when the gonads are taking over for a day or two and a boar is mounting the poor sow from whichever angle. If necessary, separate with a divider and give the boy time to calm down overnight.
Dominant sows that are not season will refuse to allow a boar to mate with them and will do their best to keep them at bay. Submissive sows on the other hand will allow a boar to dominance mate at the start as a sign of their acceptance even when they are not season.

Opposites attract: my largest 'husboar' Pioden's best friend was similar aged half-sized Helygen

Half white and half ginger: newly neutered Llelo was entirely to Miaren's liking when she managed to sneak through his cage door - and never moved out. She was on the list of potential dates for Llelo and he'd just passed tehe 6 weeks safety wait.

Seasons and special behaviours in mixed pairs
Sows have a very special whine with which to signal that they are not quite ready for mating – yet. The actual mating only happens during a relatively short slot at the end of the season.
Boars can get really worked up about the ‘nearly there’ message and can try to storm the gates early. In turn, the sows will do everything to keep their bottoms out of reach until the time is right. But despite all the drama and shenanigans you will notice that a sow will never move far from the boar she wants to mate with; and that is the crucial bit you need to hang onto when it gets a bit wild. In all this time it is still the sows who call the shots and not the boars!

Especially the first seasons in a new bond are usually much stronger ones. The shared usually very vocal and dramatic excess of emotion serves to cement the bond. You can often see your pair exchanging quiet assurances of their mutual attachment on the day after.
I divide my own ‘husbands’ into ‘rumble-singers’ or ‘mountaineers’. Especially in the early weeks, boars will express their feelings with either frequent rumble-strutting displays, often in combination with some happy popcorning even after having been given the cold shoulder by a sow or they are the active type who likes to assert themselves with regular mounting and pheromone updates sniffing.
It can take a little while until a ‘husboar’ is getting used to the fact that his life is consisting mostly of waiting for the next time his ‘sow-wife’ is willing to mate again two weeks down the line for a few very short hours...

Anyway, there is always this wonderful moment when you see a boar realising that he is living his dream. For me, this is the reason why I am such an advocate for giving ‘hopeless’ and no longer wanted fighters and bullies or beaten up mobbing victims another chance at happiness with sow instead of boar company.
Because there is true happiness and fulfilment out there for most of them!

3 years old white Carwyn with 7 years old frail ginger Ffraid

Carwyn with his young wives Briallen and Heini after Ffraid's passing

The ideal age combination?
While mutual liking and character compatibility is key for all guinea pigs much more than age, this is even more so the case with cross gender bonding. Guinea pigs of all ages and all age differences can be bonded. When rescue dating, it helps to keep an open mind to get a happy new relationship out of it.

Just to give you an idea of the possible range, here is a more extreme example: My 3 years old neutered Carwyn first lived with 7 years old Ffraid during the last weeks of her life when group life became a bit much for her and then he and five weeks old Heini fell instantly in love for the next three years. Heini has sadly followed her beloved ‘husboar’ to the Rainbow Bridge only three months after his passing; she never quite regained her old sparkle despite readily accepting a friend back as companion.
On the other hand, Heini’s slightly older, gentle but somewhat traumatised single ex-toddler pet companion Briallen didn’t accept ex-neglect breeder boar Carwyn demanding instant submission straight away. He never quite forgave her for that, and his displeasure started to verge on outright bullying over time.
Briallen now lives happily with Barri, whose introduction was not for the faint-hearted but who has settled down enormously since his initial overexcitement and who is much closer in age to her! They share a surprisingly tender and enduring bond.

These experiences are just serving as a small illustration of how crucial a character match between guinea pigs is. If the stars align, then any guinea pig bond of whatever gender combination is something to treasure! For your guinea pigs’ sake, and the satisfaction and sheer joy you get from seeing them so fulfilled and happy it is worth going that extra mile if it is within your reach!

6 years old Carwyn with his beloved 3 years old Heini who sadly followed the love of her life to the Rainbow Bridge just a few months later

Barri and his soulmate, gentle Briallen

Mixed gender pairs in a nutshell
Pros: The most stable of all pairings.
Cons: Initial acceptance and bonding is not a given and may not work out.

Forum guides for more in-depth aspects:
Bonding and Interaction: Illustrated social behaviours and bonding dynamics
When Sows Experience A Strong Season (videos)
Neutered / De-sexed Boars And Neutering Operations: Myths, Facts and Post-op Care
Bonds In Trouble

You can also find more information in Guinea Pig Magazine on Boar neutering as well as post-surgery care in issue 36


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Mar 10, 2009
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Whether you fall in love with your boys, cherish your sows or indulge in the joys of a love affair between a ‘husboar’ and his ‘sow-wife’, a lot of your practical decisions depend in reality on your individual access to a good rescue or good operating vet or your lack of it. Many of us do not have the full range of choices.  
If you can’t date your guinea pigs to ensure acceptance before you come home with a new mate, then please always have a plan B at the ready; noticeably a next-door companion with round the clock interaction through the bars.  

Never too old to fall in love: Golden oldies 6 years old Bryn and 5 years old Nia

I have been blessed to try all possible combinations over the years, but I must admit that my heart is with the mixed gender pairs even though I have and have had very happy boars and sows only bonds and would never want to miss them! They have all got different dynamics and different perks. If you can’t decide whether you like boars or sows better, or – like me – love both equally, then having a way to combine all your loves is a great option that is becoming increasingly more available to us by rescues making access to already de-sexed guinea pigs possible!  

...and at last a happy end for Dylan in the form of tiny mis-sexed rescue surrender Begw, who continues to adore her daddy-boar as an adult sow.