There's evidence of Stone Age trepanation in Europe on cows, which could plausibly be the earliest evidence of people practicing surgery on animals. https://ww

There's evidence of Stone Age trepanation in Europe on cows, which could plausibly be the earliest evidence of people practicing surgery on animals. https://www.cnn.com/2018/04/19/health/stone-age-cow-cranial-surgery/index.html https://www.cnn.com/2018/04/19/health/stone-age-cow-cranial-...