Introducing pregnant sow to a pair

Erincat55

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Hi there - I’m new here and I come with a question. And some backstory…

We’ve had guinea pigs for about three years, starting with a pair of sows. I have learned about basic care but not tons of nuances.

One of our sows died over the summer. She stopped eating and passed pretty quickly. It hit hard, especially for my daughter. We got another guinea pig pretty quickly, bringing us back to two girls.

Both my kids have been wanting more guinea pigs, and my husband and I have been leaning yes. We all really like them. Then a friend told us about a family that needs to rehome a few guinea pigs, including a pregnant sow. We agreed to take the sow in. We ordered a big new cage, and I read about guinea pig pregnancy and separating baby boys from the girls before they become fertile.

We brought our new girl (S’more) home yesterday. She is beautiful! And she’s very pregnant. We can feel the babies wiggling in her belly. S’more is just under three months old and my best guess is she is about eight weeks pregnant. She’s wide in the belly and the family we adopted her from said they started to feel the babies move last week. The dad is either her father or her brother.

But… I realized when we introduced S’more to our pair that I know nothing about guinea pig bonding. That’s what led me here.

When we put S’more in with Sisi and Lily, at first they seemed ok. They were eating together and sniffing each other. Then Sisi and Lily seemed more territorial, cornering S’more and sniffing her booty kind of aggressively. I’m not sure if there was biting (I don’t think so, though there was some face nudging?). Sisi especially seemed mad. (She’s one of our original pair and usually chill.) I tried introducing S’more twice yesterday but I got nervous and put S’more into a separate part of the cage. She stayed there last night.

I read the info pages here and some posts but I’m honestly not sure what to do! When we had two guinea pigs, the girls got along with each other so quickly I didn’t even notice a bonding period. So, this is different.

I wonder… Does it make sense to try to introduce the girls soon or might it be better to wait until the babies are born? Could neutral ground help their chances? Also, when should I move them into the new cage? (It arrives end of week.)

I can’t tell if I’m seeing bonding or rejection (or too soon to tell). I also can’t tell what is dangerous for S’more and her pups. I’d appreciate any advice. Thank you.
 
Welcome to the forum

All bonding absolutely must be done on neutral territory with no hides. If you try to put an unknown piggy directly into the cage belonging to others then unfortunately the resident girls will see her as a territory invader and the bonding will not work out .

Pregnant sows gain a special place in the hierarchy so bonding now is not wise, particularly as she is so close to the end of her pregnancy. Keep her separate but beside the others so they can interact between the bars but not be forced to form a hierarchy.
You would do better to wait until the pups are weaned (the special place in the hierarchy doesn’t get removed until after weaning) before you attempt to bond the sows.
We can help with bonding when the time comes but I have added our bonding guide below so you can familiarise yourself with the specific information

Do also be aware that bonding a single sow in with an already bonded pair can be problematic at times (a bonded pair don’t always want anybody else added in with them) but it all depends on the character compatibility, and to some extent their ages.
If you are keeping any baby sows and plan for them all to stay together then that will also play a part in whether you can form a herd.

Bonding and Interaction: Illustrated Bonding Dynamics and Behaviours

With regard to moving to a new cage - who is moving to a new cage?
 
Thank you both so much! This is very helpful. I’ll review the resources tonight.

To answer your questions @Piggies&buns - we plan to keep a baby if there’s a sow. And we would like to move everyone to the new cage. We don’t have space for both cages in the long term but we could have them both set up a while if it helps everyone get used to each other. Advice on when to move them would be great. Thanks again.
 
They would need to stay in separate cages from now until she gives birth and then for a further 3-4 weeks after birth (ie weaning).
If there are any baby boar(s) then you need to separate him/them into another cage at 21 days old or 250g in weight (whichever comes first - a single baby boar for example can reach the weight cut off earlier).

You can then try to bond the older sows (and any baby sow), in completely neutral territory once smores has weaned baby sow.

Do keep in mind that whether the bonding works will depend entirely on the character matches of all piggies involved, that there is only one dominant sow and whether the bonded pair are willing to have anyone else in their pairing (as I say getting a bonded pair to accept a single sow isn’t always straightforward) .

You won’t know until you try to bond but it is a good idea to make sure you have a back up plan for them to have to live separately (and if smores doesn’t have a baby sow and she is therefore single in a cage, the two cages then must be side by side so s’mores can interact with sisi and lily between the bars)

How old are Sisi and lily?
How big is the cage you intend them all to live in? Four sows together need 210x60cm or a 2x6 c&c

Adding More Guinea Pigs Or Merging Pairs – What Works And What Not?
 
They would need to stay in separate cages from now until she gives birth and then for a further 3-4 weeks after birth (ie weaning).
If there are any baby boar(s) then you need to separate him/them into another cage at 21 days old or 250g in weight (whichever comes first - a single baby boar for example can reach the weight cut off earlier).

You can then try to bond the older sows (and any baby sow), in completely neutral territory once smores has weaned baby sow.

Do keep in mind that whether the bonding works will depend entirely on the character matches of all piggies involved, that there is only one dominant sow and whether the bonded pair are willing to have anyone else in their pairing (as I say getting a bonded pair to accept a single sow isn’t always straightforward) .

You won’t know until you try to bond but it is a good idea to make sure you have a back up plan for them to have to live separately (and if smores doesn’t have a baby sow and she is therefore single in a cage, the two cages then must be side by side so s’mores can interact with sisi and lily between the bars)

How old are Sisi and lily?
How big is the cage you intend them all to live in? Four sows together need 210x60cm or a 2x6 c&c

Adding More Guinea Pigs Or Merging Pairs – What Works And What Not?
Thank you. It is feeling better, understanding which piggies can go together in the coming weeks.

Sisi is 3.5 years old and Lily is about five months. The new cage is C&c 2x6.
 
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