Sudden change of ingredients
The manufacturer did not indicate on the packaging that the food has a new formula. My cat, who has an extreme intolerance to fish protein, developed serious digestive problems and ended up being hospitalised. I discovered by accident that the food now contains salmon oil, which has always caused her very strong inflammatory reactions.
Any changes to the formula should be clearly marked on the packaging. I didn't think to check the ingredients every time—I trusted this food as it had always been safe and reliable before.