Reference for Bekhorot 33:24

כבשים שצמרן קשה פטורין מראשית הגז שנאמר

One authority [R'Meir] maintains that we follow the mother and this is not a nidmeh,<span class="x" onmousemove="('comment',' An animal suspected of looking like a hybrid.');">¹⁵</span>

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