Must it come from the neck? If you make the animal treif by cutting another artery, is it still called dom chaya? Avaraham wanted to draw blood even after told not to kill yitzhack, where would he cut?
Shmuel, Israel
Shalom Shmuel,
It's great to hear from you!
1. From the Gemara in Chulin 88a, I would conclude that the only blood necessary to cover is what came from the neck. There is discussion about whether the blood that reamins on the knife and on the sides of the neck need to be covered, or is it enough to cover the Dam ha'Nefesh, i.e. the blood that flows out as the animal dies.
2. I am not sure if you mean Tereifah or Neveilah. In any case, in Chulin 85a we learn that there is no obligation to cover the blood if the animal was a Neveilah or Tereifah.
3. As to where would Avraham Avinu cut, I am not sure. I assume the neck, because according to the Midrash (Bereishis Rabah 56), even after Avraham Avinu was not able to use the knife, it says he wanted to strangle Yitzchak (the Etz Yosef explains that this was based on the idea of Melikah as performed on Olas ha'Of), which also would have been at the neck.
May you continue to attain greatness in Torah and Yir'as Shamayim!
Bi'Verachah,
Yishai Rasowsky