Reference for Bekhorot 4:40

וטעמא דרבנן משום הכי הוא

[it is allowed,] how much more so in the case of a whole animal where he has not severed all connection with it?<span class="x" onmousemove="('comment',' Since the animal itself belongs to the Israelite and is not yet pregnant, and when the offspring is born, it will be in the possession of the heathen.');">²³</span>

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