From a documentary: cows are about 30% carnivore. They grow bacteria in their guts, on low quality food (grass) and then that bacteria gets devoured with the rest of the food when it's pushed in the next stomach (or intestine).
They had a hilarious setup, a cow with a plastic flap attached to the side. They would open the flap to get instant access to the guts of the cow to collect samples of food.
Consuming prokaryotes i.e. bacteria as part isn't the same thing as eating the tissue of animals. By that definition, just about every living animal is a carnivore, which would erase the relevant distinction (eating plants versus animal tissue).
They had a hilarious setup, a cow with a plastic flap attached to the side. They would open the flap to get instant access to the guts of the cow to collect samples of food.