Reference for Chullin 149:5

רבי יוסי הגלילי היא

For it was taught: R'Simeon B'Eleazar says in the name of R'Jose the Galilean: It contracts food uncleanness,<span class="x" onmousemove="('comment',' This living animal, extracted out of the slaughtered dam's womb, would be rendered unclean, like an ordinary foodstuff, if it came into contact with uncleanness.');">³</span>

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