Reference for Chullin 149:22

נולדו בדגים סימני טרפה מהו

And according to him who holds that a trefah cannot continue to live this question can also be asked, for perhaps this is so<span class="x" onmousemove="('comment',' Sc. that a trefah cannot continue to live and so might be regarded as dead.');">¹³</span>

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