Siman 26

The Rambam wrote at the beginning of chapter 7: If one began the shechitah and slaughtered the entire trachea and afterwards the lung was punctured, and afterwards he completed the shechitah, this is treifah, since it was punctured before the completion of the shechitah; and so too anything similar to this. Thus far his words. And so ruled the Tur and Shulchan Aruch. And the explanation of his words is that it is known that the lung is suspended from the trachea, and it is also known that after the valid shechitah, if the lung is punctured, the status of treifot does not apply to it at all. If so, there is reason to say that when the trachea is slaughtered and the esophagus is not yet slaughtered, this organ which is suspended from the trachea—such as the lung—the matter of treifot should not apply to it at all, for its vitality has already been severed and it is considered as if it were placed on its own. Nevertheless, we do not say so, for as long as it has not been slaughtered in its entirety, there is still vitality to all the organs because they draw from one another, and half the vitality of the lung depends also on the esophagus, and there is treifah for half-vitality. And so too anything similar to this, such as if he slaughtered the esophagus first, and before the slaughtering of the trachea the intestines were punctured; even though the intestines are suspended from the esophagus, nevertheless, as long as the trachea has not been slaughtered, they still have half-vitality from the trachea, and there is treifah for half-vitality. And this is the opinion of the Rif and the Rosh [chapter 2, section 11] and other great ones among the Rishonim.

And behold, in the Gemara [32b], there is one who says explicitly: if one slaughtered the trachea and afterward the lung was perforated, it is kosher. Our teachers rejected this from the halakha because there is one there who disagrees with this and holds that if there is no treifa for a partial life, then even if the intestines were perforated after the slaughter of the trachea, it is also kosher, even though the intestines are dependent on the esophagus; for after the partial life is concluded, the status of treifa is no longer relevant. And if there is treifa for a partial life, then even if the lung was perforated, it is a treifa. And our teachers explain that this is what he meant: just as when the intestines are perforated after the slaughter of the trachea you admit that it is a treifa, so too when the lung is perforated. And the halakha is like him.

But Rashi, of blessed memory, and the Maor and the Rashba [Torat HaBayit, House 2, Gate 3] hold that if one slaughtered the trachea and afterwards the lung was perforated, it is kosher. For these teachers of ours explain that the one who disagrees holds that even if the intestines were perforated after the slaughter of the trachea it is kosher, because there is no treifah for partial life, and we do not rule like him. But if the lung was perforated after the slaughter of the trachea or its majority, or the intestines were perforated after the slaughter of the esophagus or its majority, there is no one who disagrees, and all admit that it is kosher. And this opinion was not brought in the Shulchan Aruch at all, and it is simple that we rule according to the first opinion, as it is a doubt regarding a Torah law. [And one must look into the first opinion, for there on page 33a Rav Aha bar Yaakov said: learn from this from Resh Lakish that we invite, and the Gemara deliberates on this; if so, the halacha is like Resh Lakish. And I found in the Torat HaBayit who raised this difficulty, and even for the one who rejects it, it is for another reason: "Is there anything etc." Furthermore, the Rambam in chapter 9 of Laws of Kings ruled in the law of the Beraita like Rav Aha bar Yaakov, and this requires great study]:

The Tur and the Shulchan Aruch wrote: If the veshet was perforated during the time of shechitah opposite the place where he already slaughtered, it is treifah. Thus far their words. The commentators explained that this is specifically before the slaughtering of the majority of the veshet, but after the slaughtering of its majority, even if the kaneh has not yet been slaughtered, nevertheless, a perforation of the veshet is nothing, since it has already been slaughtered and is considered as if it were placed in a box. And even though regarding the perforation of the intestines they hold that it is treifah even after the slaughtering of the veshet, and similarly a perforation of the lung after the slaughtering of the kaneh, as has been explained, and we do not say that it is considered as if it were placed in a box, nevertheless, regarding the veshet itself, it is impossible for a perforation to disqualify it after the majority of it has been slaughtered. And similarly, when the majority of the kaneh has been slaughtered, a severance of the windpipe does not disqualify it even before the slaughtering of the veshet.

And in my humble opinion, it appears that a distinction should be made in this: for certainly the piece of the esophagus that is above the shechitah toward the head is considered as if severed; however, regarding the piece of the esophagus that is above the shechitah toward the intestines, why should it not be rendered treifah by a perforation like the intestines themselves? And one cannot say that since half the organ is considered as if severed, automatically the second half is also considered as if severed, for if so, if we consider the entire organ as completely severed, you have no greater perforation in the intestines than this after we consider the esophagus as severed from them. Rather, certainly that which is still attached to the body, we judge them as half alive, and there is a status of treifah for half-vitality according to the opinion of the Rambam, the Tur, and the Shulchan Aruch as I have written. And it appears to me that, on the contrary, this is why the Tur and the Shulchan Aruch left their words unspecified and did not write "at the time of the shechitah of the esophagus," because it is taught in a disjunctive manner: that which is toward the body is at the time of the shechitah of the two simanim, and that which is toward the head is at the time of the shechitah of the esophagus, and the same applies to the lung during the shechitah of the trachea. [And I am very much astonished that they brought proof from the Rashba in a Responsum who wrote so, for behold the Rashba holds like Rashi as I wrote in section 3, and even though he wrote this according to all opinions, nevertheless his opinion in practice is like Rashi; and perhaps he wrote so regarding that which is toward the head. And from Tosafot 8a there is no proof at all, for they did not descend to the ruling of Reish Lakish on 32b. And furthermore, they also did not write "at the time of the shechitah of the esophagus." And see the Bach who hesitated regarding the essence of this reasoning, and according to what I wrote to distinguish between the side of the head and the side of the body, it is settled simply. And the Tevuot Shor also forbids where it is not a case of great loss, see there. And it appears to me that toward the body, even in a case of great loss one should not permit, and toward the head, even not in a case of great loss it is permitted].

It is a simple matter in the mouths of all the poskim that after the majority of the simanim have been slaughtered in a beast, or the majority of one siman in a bird, a hole in the esophagus or a severance of the windpipe in the trachea no longer renders it invalid. There is one of the great authorities who wishes to be stringent in this until one slaughters the entire siman, and his reasoning is that we also forbid displacement in the final minority; and what difference is there to me between displacement in the final minority or a hole in the esophagus in the final minority? And if it is because a hole in the esophagus is not the way of slaughter, displacement according to the Bahag is also not the way of slaughter [Kereiti U-Peleiti]. But there is no basis for this stringency, for certainly that which is not the way of slaughter does not render it invalid after the slaughter of the majority of the simanim. And that which displacement renders invalid in the final minority is because it is of the five laws of slaughter, like hagramah which renders invalid in the final minority even though it is not the place of slaughter, as we explained the reason in siman 24, section 25 [and I do not understand his proof from Tosafot 30b, for the Tosafot do not hold like Rashi regarding the final minority, and also regarding hagramah they wrote so, see there; and his proof from the Bach is very astonishing, for the Bach did not write at all regarding the final minority, but rather because the second siman had not yet been slaughtered, as I have written].