Reference for Chullin 166:18

נהי דלמטה לא אפשר למעלה אפשר ליעביד כסוי

Has it not been taught: R'Jonathan B'Joseph says: If a man slaughtered a wild animal and then he slaughtered cattle, he is exempt from covering up the blood; if he slaughtered cattle and then a wild animal he must cover up the blood?<span class="x" onmousemove="('comment',' Although in this case there is no dust beneath the blood of the wild animal, for it lies above the blood of the cattle, it must nevertheless be covered up on top. Likewise the blood of a bird sacrifice upon the altar should have to be covered up on top.');">¹⁰</span>

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