Reference for Chullin 73:32

למאי הלכתא

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 a dying animal which is not physically deficient is forbidden, is ther any doubt about a trefah?<span class="x" onmousemove="('comment',' So that the verse prohibiting trefah would be superfluous.');">¹⁷</span>

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