chewing but spitting

Hi, I’m wondering if anyone can give me some advice. My guinea pig has been struggling to eat. He is picking up food and seems really determined to eat but also seems unable to bite or chew it properly. And so just spits it back out again/drops it. I’ve tried him on lettuce, kale, celery...

I'm really hoping someone can help with this. My little Bentley has been losing weight quickly over the last week or so. I thought it was because we had introduced a new pair of piggies and he was just acting up. Checked his teeth the other day and one was chipped and the other looked way to...