The laws of sheḥita were given to Moshe at Sinai, as it is stated: “You shall slaughter from your cattle and from your flock, which the Lord has given you, as I commanded you” (Devarim 12:21; Ḥullin 28a). In sheḥita, the two simanim must be cut: the windpipe and the esophagus. These simanim are the channels of life: the windpipe supplies oxygen, and the esophagus supplies food. When they are cut, the animal’s source of life is severed (SA YD 21:1). To spare the animal suffering and because of the prohibition of eating blood, the arteries and veins must be cut together with the simanim. Once the arteries are cut, the animal no longer feels pain and its life departs without suffering; cutting them also drains the blood that is forbidden to eat, as explained below in section 3.[1]
Sheḥita is performed with a sharp knife drawn across the soft front of the neck, where the simanim and arteries are located. If, however, one slaughtered from the back of the neck, then as soon as the knife struck and cut the spinal bone, the animal became a neveila, and continuing the cut until reaching the two simanim would no longer help. If one began slaughtering from the side of the neck, the sheḥita is valid as long as both simanim were cut without touching the spinal bone. In turkeys and doves, the simanim are located at the sides of the neck. The shoḥet must position the birds so that the simanim face the front of the neck, ensuring the cut does not strike the spinal bone (SA YD 20:3–4).
Five laws of sheḥita were given to Moshe at Sinai: shehiya, derasa, ḥalada, hagrama, and ikur. If any of these requirements is not met, the sheḥita is invalid and the meat is classified as neveila.
Shehiya refers to a pause during the act of sheḥita. The act of sheḥita must be continuous; if the shoḥet pauses even momentarily, the sheḥita is invalid. True, the Sages said that a pause invalidates only if it lasts as long as it takes to perform sheḥita (Ḥullin 32a). Nevertheless, according to many Rishonim, this means the time it takes to cut most of the simanim – an interval of less than a second, too brief to measure – and the practice is therefore to invalidate the sheḥita after any pause at all (Rashi; Mahari Weil; Rema YD 23:2; Kaf Ha-ḥayim 13).
Derasa refers to slaughter by pressure rather than by cutting. Sheḥita must be performed by drawing the knife back and forth across the neck, not by pressing the knife into it. Any pressure of the knife into the neck, even slight pressure, is derasa and invalidates the sheḥita. If the knife is at least twice the width of the neck, one may, when necessary, perform a valid sheḥita with a single cutting motion. Ideally, however, one should use such a knife while moving it back and forth, so as to avoid any possible concern of derasa (SA YD 24:1–6; Shulḥan Arukh Ha-Rav 9; Simla Ḥadasha 3).
Ḥalada refers to concealed sheḥita, where the knife is inserted into the neck and cuts from within. Such a sheḥita is invalid. The word ḥalada denotes concealment, like a weasel (ḥulda) that hides in holes, because the knife is concealed inside the neck. If an animal had heavy wool on its neck and the shoḥet inserted the knife beneath the wool and slaughtered, the sheḥita is invalid out of concern for ḥalada, and the animal’s meat is forbidden to eat (Ḥullin 30b; SA YD 24:7–8). When an animal has thick wool on its neck, the practice is to shear it before sheḥita.
Hagrama refers to slaughtering outside the section of the neck designated for sheḥita. The cut must not be made too high, toward the mouth, or too low, toward the lungs and stomach; if it is, the sheḥita is invalid. For this reason, the accepted practice is to slaughter near the middle of the neck, avoiding any concern of hagrama (SA YD 20:1–3; 24:12–14).
Ikur refers to sheḥita in which the simanim are torn, uprooted, or displaced rather than cut properly in their place. It invalidates sheḥita in one of two ways. The first involves the knife: if the blade has a nick, it can tear or puncture the windpipe and esophagus rather than cut them cleanly, and the sheḥita is invalid. The second involves the simanim themselves: if one of them has become dislodged from its natural place in the neck, and it is cut in that state, the sheḥita is invalid (SA YD 24:15–18).
