The thing is cows eat metal while grazing freely too.

I have a background in farming and there has been cases of cows ingesting rather weird things absolutely on their own.

One case I remember hearing about was a cow eating a pack of leftover bolts from construction teams.

How we treat these animals is a blessing compared to how Mother Nature would treat them. We protect them from parasites, bacterial infections, malnutrition, rabies, predators, the weather, physical injuries and yes, ingesting things they’re not supposed to.

I don't know. I feel like a cow without humans is most likely to end up being slowly tear apart by a predator