Reference for Chullin 149:23

תיבעי למ"ד טרפה חיה ותיבעי למ"ד טרפה אינה חיה

only in the case of animals, since to its kind slaughtering applies,<span class="x" onmousemove="('comment',' Since slaughtering applies to animals and a trefah cannot be slaughtered it might well be regarded as dead, but this is not so in the case of fishes.');">¹⁴</span>

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