Pets have diet sensitivities too, which can upset their stomachs. My cat used to occasionally throw up but with her current food she has gone for more than a year without any events.
By eating spoiled and contaminated food, ancient people were certainly getting internal parasites too (also something that a big fraction of pets have).
By eating spoiled and contaminated food, ancient people were certainly getting internal parasites too (also something that a big fraction of pets have).