[PrincessDiana]

Originally Posted by Ellie May

Proteins, not fat, normally cause allergies. A pet can be seriously allergic to chicken, but not chicken fat. Ten documented case studies incriminated beef, dairy products and wheat as accounting for 68% of reported allergy cases. Soy is one of 4 ingredients causing 25% of recorded cases. Soy is known for causing gas. Corn is often incriminated as causing adverse food reactions but in 10 different peer reviewed studies it was not listed in the top 68% or the next 25% of ingredients causing adverse reactions.
Eagle Pack Pet Foods, Inc.

If my dog/cat is allergic to chicken protein, why can he/she eat a product that contains chicken fat?
Typically, irritants are proteins (animal or plant), and not fats. As a result, if your pet is allergic to chicken protein, it will not be allergic to chicken fat. Products that are chicken-free (no chicken, chicken organs, or chicken eggs) but include chicken fat should be safe to feed. Please consult your veterinarian if you have any questions.
Common Questions | Nature's Variety

I think the answer is it will be fine but there is always a chance that they could be hypersensitive to the fat also which would be very rare.

Silly me. The answer WOULD be right there on the website. Thanks for finding it!