Reference for Chullin 145:14

מה מצינו בטרפה ששחיטתה מטהרתה אף שחיטת בהמה תטהר את העובר:

For Samuel's father stated: A trefah animal that was slaughtered renders holy things unclean.<span class="x" onmousemove="('comment',' So according to Maim. Yad, Aboth Hatumah, II, 8. According to Rashi (infra 123b) a trefah consecrated animal that was slaughtered still renders unclean.');">⁶</span>

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