The feathers and the down acquire tumah and convey tumah, but do not combine. R’ Yish-mael says: The small feathers com-bine. The beak and the claws acquire tumah and convey tumah and combine. R’ Yose says: Even the tips of the wings and the tip of the tail combine, since these are left on fattened birds.

The carcass of a nonkosher bird needs intention and preparation, it conveys the tumah of foods in the volume of an egg, half a half-loaf disqualifies a person, it does not have [the law of] the volume of an olive in the esophagus, someone who eats it does not need the setting of the sun, one is not liable on its account for entering the Temple, but terumah is burned on its account, someone who eats a limb [severed] from it while it is alive does not receive forty [lashes, and] its slaughter does not render it ta-hor. The large feathers and the small feathers acquire tumah and convey tumah and combine. The beak and the claws acquire tumah, convey tumah, and combine.

And with animals: The hide, the gravy, the spices, the elal, the bones, the gidim, the horns, the hooves, combine to convey the tumah of foods, but not the tumah of neveilah. Similarly, [if] someone slaughters a nonkosher animal for a non-Jew and it is convulsing, it conveys the tumah of foods, but not the tumah of neveilah until it dies or until he chops off its head. [The Torah] has provided more things that convey the tumah of foods than that convey the tumah of neveilah.

Food that contracted tumah from an av hatumah and food that contracted tumah from a derivative tumah combine with one another to convey tumah according to [the level of] the lesser of the two. How so? The volume of half an egg of rishon food and the volume of half an egg of sheni food that one mixed together, [is] a sheni. The volume of half an egg of sheni food and the volume of half an egg of shlishi food that one mixed together, [is] a shlishi.  The volume of an egg of rishon food and the vol-ume of an egg of sheni food that one mixed together, [is] a rishon. [If] he separated them, this is a sheni and this is a sheni. [If] this one fell by itself and that one [fell] by itself onto a loaf of terumah, they disqualify it. [If] they both fell together, they make it a sheni.