Reference for Chullin 73:26

ודלמא היינו טרפה היינו מסוכנת ולעבור עליו בעשה ולא תעשה

that is to say, when it is dead the Divine Law terms it nebelah, but whilst still alive it is not termed nebelah.<span class="x" onmousemove="('comment',' The position now is that it is proved that a dying animal is permitted, for if forbidden then the prohibition of nebelah is superfluous.');">¹²</span>

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