Reference for Chullin 54:16

באיזו תורה שוותה בהמה לעוף ועוף לבהמה

But then it should follow, should it not, that as in the case of birds [the nipping is done] close to the back of the nec so in the case of cattle [the slaughtering should be done] close to the back of the neck?

Jastrow