Bikkurim, Chapter Two, Mishnah Eleven
The final mishnah of this chapter discusses ways that a koy is either different from both a behemah and a hayyah and ways that it is similar to both.
And how is [a koy] neither like a behemah nor like a hayyah?
1) It is forbidden because of kilayim [to yoke it] with either a behemah or a hayyah.
2) One who deeds his son his behemah and his hayyah he has not [thereby] given him the koy.
3) If one says, I will become a nazirite if this is [not] a hayyah or a behemah, he is a nazirite.
In all other ways it is like a behemah and a hayyah:
4) It requires slaughtering (shehitah) like them both;
5) It carries carrion impurity;
6) And to it applies the law relating to a limb of a living being like them both.
Section one: It is forbidden to yoke together two animals of different species. Since a koy might be a behemah, it cannot be yoked with any hayyah, and since it might be a hayyah, it cannot be yoked together with any other behemah.
Section two: If one writes a will to his son, bequeathing to him his behemot and his hayyot, he has not bequeathed to him his koy, because a koy is neither a behemah or a hayyah.
Section three: The person here makes a bet that an animal approaching is either a behemah or a hayyah. If he loses his bet, he will be a nazirite. Although this would seem to be a hard bet to lose, somehow he does lose the bet, for a koy is indeed, neither a behemah nor a hayyah.
Section four: The mishnah now begins to list ways in which a koy has the same rules that apply to a behemah and to a hayyah. The first is that one who wishes to eat a koy must slaughter it in the appropriate manner.
Section five: Carrion (nevelah) is an animal that was not slaughtered in a proper manner. The nevelah of a kosher animal is impure, and since the koy is kosher, its nevelah is impure.
Section six: It is forbidden to eat the limb of a living animal. This law applies only to beasts and wild animals but not to reptiles and other non-mammals. It applies to the koy in the same way that it applies to all behemot and hayyot.