Reference for Niddah 48:3

במה דברים אמורים בשלא כלו לו חדשיו אבל כלו לו חדשיו מותר

but permitted when still in its dam's body.<span class="x" onmousemove="('comment',' As part of that beast which was a clean one and ritually slaughtered. ');">³</span>

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