As weird as this may sound, I mean literally reach in and touch the inside of the cow!

In case you didn’t know animals can live perfectly well with a permanent hole in their stomachs. Scientists call these surgically made holes, fistulas, which are covered by a canulla, a sort of cover from the outside world. They are used to test the digestibility of various cattle food, the cows are fed and as the food passes through her stomachs, scientist can just reach in and see how it is processed. As brutal as it might look, this doesn’t hurt the animals at all, it actually prolongs their life, in case of stomach disease, they can receive helping medicine directly in there.

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