First of all don't worry about the quality of the food, cats prefer foods with a strong odor so as long as she eats, that's fine.
In my experience the two most common causes of food allergies are poultry and an ingredient called carageenan:
Check the labels to see if Laci's food includes carageenan.
I also would like you to stop any poultry for a two week trial period.
Since she likes fish lets stick to that or beef, rabbit, venison or lamb.
You will find tasty non allergic foods here:
It is also best to feed pate foods and stop anything dry or with chunks, pieces or shreds when she is vomiting.
In her evening meal add one quarter of a ten mg pepcid a/c (famotidine). I usually add it to a tablespoon of baby food with no onion or garlic Or canned cat food.
If she ever has diarrhea add one tablespoon of rice cereal or boiled white rice to a can of food.
If she gets dehydrated give her tuna water drained from the can.
Please let me know how she is doing on this non poultry diet.
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