Reference for Bekhorot 51:50

אלא

[But if one actually] plucks, is there any authority who allows?<span class="x" onmousemove="('comment',' According to the view of the Rabbis who declare it is forbidden, he is certainly a transgressor. Tosaf. adds that since we are dealing here with an unblemished animal, even Akabya would consider it wrong in accordance with the Baraitha above.');">²²</span>

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