The cat vomited up partially digested cat food.
There are several possible reasons why a cat might vomit partially digested cat food:
1. If a cat swallows too quickly or the cat food is too hard, it can put a strain on its gastrointestinal tract and cause vomiting, which may result in the cat vomiting partially digested cat food.
2. If the cat food is spoiled, the cat may vomit due to a foreign object in its body, expelling spoiled, partially digested cat food. 
Third, the cat may be suffering from other illnesses that cause vomiting, such as gastroenteritis, feline panleukopenia, poisoning, etc.
If a cat vomits undigested cat food, it could be due to poor quality cat food causing gastrointestinal upset, indigestion, or hairballs.
Pet owners should closely observe their cats' condition, promptly identify the cause, and then help their cats recover. It's crucial not to let your guard down.
