[There is] a stringency in chelev over blood, and [there is] a stringency in blood over chelev. The stringency in chelev is that one is guilty of me’ilah on its account, and one is liable on its account for piggul, leftover, and tumah, which is not the case with blood. The stringency of blood is that [the prohibition of] blood applies to domestic animals, beasts, and fowl, both nonkosher and kosher, whereas [the prohibition of] chelev applies only to kosher domestic animals.