What's wrong with this chicken? Is it sour crop, an absess, or something else?

[klmclain1]

eewwwwwwwwwwwwwwwww.... I have no clue.

 

[nurse_turtle]

Abscess. Eek.

 

[shadow rabbit10]

I agree. I know they are two different animals, but I had a rat with an abscess and when the vet popped it, a pussy, smelly, yellow green liquid came out. When abscesses are not dealt with quickly, the puss goes into the bloodstream and kills the animal.