Reference for Chullin 73:23

היינו נבלה היינו מסוכנת מחיים בעשה לאחר מיתה בלאו

is forbidden to be eaten, it follows that a dying animal is permitted; for if you were to say that a dying animal is forbidden, [then it will be asked:] if it is already forbidden whilst still alive, is there any doubt after death?<span class="x" onmousemove="('comment',' Since generally a nebelah is in a lingering dying condition previous to its death. So that the 'law prohibiting nebelah would be superfluous.');">⁹</span>

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