I need help finding out if my guinea pig's behavior is a warning sign or not..

[pr0phecypssy]

I've had my guinea pig Gizmo for about a year or so, he was a year old when we received him from his previous owners and he was such a loving and curious little piggy. I absolutely love him, and I always tried to spend time with him whenever I could despite my busy schedule. We also have another guinea pig, Butterscotch, who we got around November or December. I believe he lived with his previous owner for a long while, and he doesn't like to be touched at all. I assume it's because he isn't used to us, so I try to just hand-feed when it comes to veggies but respect his boundaries.
Gizmo however loved being petted anywhere, he would flatten and stretch out and purr and sometimes even popcorn while he's being petted, if i took my hand away he would crane his head up in the air and look and sniff around for me and then immediately flatten and stretch out when i lower my hand and he smells me, before i even pet him! However, tonight he didn't respond to me at all, he even turned his head away from my hand. I almost cried. I'm so worried. He didn't even seem to care for being petted. I tried anyway, and he may have squeaked a couple of times and flattened once, but he just didn't seem as affectionate as usual. It was just a very noticeable difference. I cleaned his cage and Butter's and gave them hay and pellets as per usual, and if this helps with discerning if he's alright, the two are currently separated by a gate partition due to fighting during the initial months of contact. Butter was extremely aggressive, we had to separate them for Gizmo's safety. Nowadays, they seem to be growing more tolerant of each other. Sometimes they touch noses and run around their respective areas coming back to touch noses every time they meet. We haven't removed the gate yet, due to Butter still being standoffish with us and unsure how he would act with Gizmo if they were left alone together.
Gizmo doesn't exhibit any of the obvious signs of sickness, he simply wont respond as usual, acting distant and uninterested. However, he's more than happily eating his food, especially his hay. He's usually so excited and happy to be petted and now he just stands quietly, not even responding to me. I want to know if this is a sign of something hurting him or something wrong with him, or if there's anything I can do to make him more happy. I just want him to be happy.

 

[Piggies&buns]

One indicator of finding out if something is going on medically is to switch from the routine weekly weight checks and instead weigh him daily. When a piggy unwell their hay intake often reduces and the only way to tell a piggy is eating enough hay is through keeping track of their weight.

If you are concerned about his health or id there has been any reduction in his weight, step in with syringe feeding and see a vet.

Weight - Monitoring and Management

Otherwise, he may simply have not wanted to be touched at that point.
Two of my four boys are very cuddly lads but there are times when they don’t want to be touched.


Something else I wanted to pick up on.
You say you have not tried to remove the divider. I just wanted to mention that you should not just remove the divider between their two cages in any event. Any bonding needs to be done properly on neutral territory.

You say butterscotch was aggressive.
What behaviours did you see?
Was it a full on fight?

If you have tried to bond them before and they have had a full on fight, then do not try to bond them again. A full fight is incompatibility and putting them together will most likely end in a fight again.

To add for information you cannot bond just by removing the gate anyway - that would cause a fight as each other would wander into each other’s territory. Any bonding must always be done in neutral territory.
Equally, the interactions at the divider are not an indication of whether they want to be together in any event. They may be happy to communicate and interact at the divider but that does not mean they are compatible and capable of sharing territory if fights have occurred previously.