Reference for Chullin 144:7

טול לך מה שהבאת הרי שנולדה טרפה מן הבטן מנין

YOU MAY STATE THIS OF AN UNCLEAN ANIMAL FOR AT NO TIME WAS IT FIT [FOR SLAUGHTERING]; CAN YOU ALSO STATE THIS OF A TREFAH ANIMAL WHICH HAD A TIME WHEN IT WAS FIT<span class="x" onmousemove="('comment',' I.e., before it was rendered trefah.');">²</span>

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