Reference for Chullin 135:33

לא נצרכה אלא למקום חתך הכא נמי לא נצרכה אלא למקום חתך

If the dam was slaughtered, and then it withdrew it within,<span class="x" onmousemove="('comment',' I.e., the dam was slaughtered whilst the limb of the foetus protruded from its womb, but immediately after the slaughtering the limb was withdrawn into the womb.');">¹⁸</span>

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