יורה דעה נ״דYoreh De'ah 54

Se’if 1א׳

הַבְּהֵמָה יֵשׁ לָהּ כ"ב צְלָעוֹת גְּדוֹלוֹת שֶׁיֵּשׁ בָּהֶן מֹחַ, י" א מִכָּאן וְי" א מִכָּאן, וְכָל אַחַת תְּקוּעָה בַּחוּלְיָא שֶׁלָּהּ, וּלְמַטָּה מֵהֶן יֵשׁ עוֹד צְלָעוֹת קְטַנּוֹת שֶׁאֵין בָּהֶם מֹחַ, וּלְאַחַר שֶׁכָּלוּ כָּל הַצְּלָעוֹת יֵשׁ חוּלְיוֹת שֶׁאֵין צְלָעוֹת תְּקוּעוֹת בָּהֶן. נִשְׁבְּרוּ רֻבָּן שֶׁל כ"ב הַגְּדוֹלוֹת מֵחֶצְיָן וּלְמַעְלָה כְּלַפֵּי הַשִּׁדְרָה, בֵּין שִׁשָּׁה מִצַּד זֶה וְשִׁשָּׁה מִצַּד זֶה, אוֹ י" א מִצַּד זֶה וְאֶחָד מִצַּד הַשֵּׁנִי, טְרֵפָה. וְאִם נֶעֶקְרוּ מֵהַחוּלְיָא וְהַחוּלְיָא קַיֶּמֶת, הָוֵי כְּאִלּוּ נִשְׁתַּבְּרוּ.

An animal has twenty-two large ribs that have marrow in them, eleven on this side and eleven on that, and each one of them is set into its own vertebra; and below them there are further small ribs that have no marrow in them; and after all the ribs come to an end there are vertebrae into which no ribs are set. If the greater part of the twenty-two large ones were broken, from their middle upwards toward the spine - whether six on this side and six on that, or eleven on this side and one on the other side - it is a tereifah (an animal with a fatal defect). And if they were torn loose from the vertebra and the vertebra stands, it is as though they had been broken.

Se’if 2ב׳

נִשְׁתַּבְּרוּ צְלָעוֹת הַקְּטַנּוֹת שֶׁאֵין בָּהֶם מֹחַ, כְּשֵׁרָה.

If the small ribs, that have no marrow in them, were broken, it is fit.

Se’if 3ג׳

נֶעֱקַר מֵהַצְּלָעוֹת גְּדוֹלוֹת צֶלַע וַחֲצִי חוּלְיָא עִמָּהּ, טְרֵפָה. הַגָּה: וְדַוְקָא נֶעֶקְרָה, אֲבָל אִם אֵרַע כָּךְ חֲסֵרָה, כָּשֵׁר. וְהוּא הַדִּין אִם יְתֵרָה חוּלְיָא אַחַת, אֲפִלּוּ עִם ב' צְלָעוֹת, כְּגוֹן שֶׁנִּמְצְאוּ י"ב צְלָעוֹת גְּדוֹלוֹת שֶּׁיֵּשׁ בָּהֶן מֹחַ, כָּשֵׁר (ת"ה סִימָן קע"ז) וְכֵן אִם נִמְצְאוּ בְּצַד אֶחָד ט"ו צְלָעוֹת וּבְצַד אֶחָד כְּתִקּוּנוֹ (רַשְׁבָּ"א שצ"ו).

If a rib was torn loose from the large ribs, and half a vertebra with it, it is a tereifah. Hagah [Rema]: And that is specifically where it was torn loose; but if it happened to be lacking in this way, it is fit. And the same law applies if it has one vertebra extra, even with two ribs - such as where twelve large ribs that have marrow in them were found - it is fit (Terumat haDeshen, siman 177); and likewise if fifteen ribs were found on one side and on the other side it is as it should be (Rashba 396).