Special Needs Sick guinea pig help

[Silverwind]

While my husband and I were away, our son's old guinea pig had maybe a stroke. When I looked in on him yesterday I realized that he is emaciated, has limited mobility, and is now blind. He has sores on his feet from sitting in his own urine. I decided to bring him to our local humane society to have him euthanized, and we spent the evening cuddling him and feeding him apples. This morning I went to get him, and he seemed much spunkier and is hungry, so I decided we can try to nurse him back to health. We are going to treat his wounds and hand feed him until he is more able to feed himself. My question is- what foods are best to help him put weight back on?

 

[bpatters]

Critical Care, if you can find it. Or a pellet slurry.

See https://www.guineapigcages.com/forum/threads/115000-Handfeeding-a-guinea-pig