guinea with (I think) bad bumble foot

[azygous]

Yes, very infected feet. To begin, I would start an oral antibiotic and treat his pain, which must be considerable, with baby aspirin. I concur with @Wyorp Rock that amoxcillin would be a good choice. He can have one whole baby aspiring in the morning and one in late afternoon.

When severe frostbite and infection occurs on extremities, chickens' immune response is to wall off the damaged tissue with swelling, blocking blood flow. Eventually, deprived of a blood supply, the damaged part dries up and falls off, yes, even entire feet.

No need to euthanize him at this time unless he becomes immobile with pain and refuses to eat, and loses all interest in life. I'd guess he's far from being to that point.

After soaking his feet and removing all dirt, please post new pics, and we might direct you to do a bit of wound debriding to remove dead tissue and pus.

 

[AmyJane725]

Do guineas normally have those little yellow nodules all over the bottoms of their feet?

 

[Eggcessive]

I agree with what @Wyorp Rock and @azygous advised. That is interesting about the yellow texture on the feet—I haven’t seen that on chickens, but am not familiar with guinea fowl. It does appear that there was some frostbite damage by the marbling of the skin and the stubbing of the toes. I would really soak the feet for about 30 minutes a day in Epsom salts and gently wash them with a toothbrush to get some of that stuff off. Vetericyn Wound Spray is good for disinfecting the legs and feet. Coconut oil or castor oil are also good for coating the feet and legs.

 

[Bug n Flock]

That's good news. We have only had him a couple days but like the little guy and really want to save him. Cleaned the feet up good, we are doing prep for a storm about to roll in, with take new pics when we can. Putting him in a dog crate on puppy pads and bringing him in the house to keep clean and dry easier. We don't have baby asprin and are probably rained in until next week, but will get some the next time we can get out. I'll start him on the fish mox then. Any idea on dose? The capsules are 250mg each. Should we break these open and add to food or water or what?

 

[Wyorp Rock]

That's good news. We have only had him a couple days but like the little guy and really want to save him. Cleaned the feet up good, we are doing prep for a storm about to roll in, with take new pics when we can. Putting him in a dog crate on puppy pads and bringing him in the house to keep clean and dry easier. We don't have baby asprin and are probably rained in until next week, but will get some the next time we can get out. I'll start him on the fish mox then. Any idea on dose? The capsules are 250mg each. Should we break these open and add to food or water or what?

I did not find anything that said you couldn't give Amoxicillin to Guinea Fowl, but you may want to research to make sure.
Dosage of Amoxicillin for birds is 57mg per pound of weight given orally twice a day.

Weigh him and let us know what that is, we will help you with the dose.