My wife has a allergic reaction to shrimp. Interestingly she can eat most wild caught shrimp without issue but has a pretty distinct reaction to the farm raised

My wife has a allergic reaction to shrimp. Interestingly she can eat most wild caught shrimp without issue but has a pretty distinct reaction to the farm raised type (oral swelling, itching, hives). I don't know enough about the difference between the two to know why this is. Maybe farmed are a different species, or it's the diet they are exposed to, or they are treated with something.