Reference for Chullin 102:5

ת"ש

Come and hear: A calf that was born on a festival may be slaughtered [the same day] on the festival!<span class="x" onmousemove="('comment',' V. Bez. 6b. The prohibition of mukzeh does not apply, for the dam as well as its young were designated for food on the Festival, v. supra 14a. There is evidently no apprehension whatsoever of an internal injury caused during calving.');">⁴</span>

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