Reference for Chullin 204:1

אכל צפור טהורה בחייה בכל שהוא במיתתה בכזית

If a person ate a clean bird whilst it was yet alive, however small it was [he is liable],<span class="x" onmousemove="('comment',' He is liable for transgressing the prohibition of a limb of a living creature, for the eating of the entire bird alive is certainly equivalent to the eating of a limb severed from the living bird. It is apparent, therefore, that Rab does not insist upon the minimum quantity of an olive's bulk with regard to this prohibition, thus contradicting his own previous statement.');">¹</span>

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