Reference for Chullin 148:59

מגע טרפה שחוטה

but according to you [it will be asked:] whereby was it rendered susceptible to uncleanness? - He replied: By the slaughtering, and it is in accordance with R'Simeon's view.<span class="x" onmousemove="('comment',' V. supra 33a. As the slaughtering is also effective for the foetus the latter is thereby rendered susceptible to uncleanness.');">³⁰</span>

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