Question: 

Is it permissible to feed your pet cat dry food which contains haraam ingredients? Or should you only feed halaal food to your pets? 

Answer: 

It is not permissible to feed animals/pets food which contains Haraam ingredients. i It will only be permissible to feed Halaal food to animals and pets.

AND ALLAH TA’AALA ALONE IN HIS INFINITE KNOWLEDGE KNOWS BEST