Pesachim7: 11
כָּל הַנֶּאֱכָל בְּשׁוֹר הַגָּדוֹל — יֵאָכֵל בִּגְדִי הָרַךְ, וְרָאשֵׁי כְנָפַיִם וְהַסְּחוּסִים.  הַשּׁוֹבֵר אֶת הָעֶצֶם בַּפֶּסַח הַטָּהוֹר, הֲרֵי זֶה לוֹקֶה אַרְבָּעִים; אֲבָל הַמּוֹתִיר בַּטָּהוֹר, וְהַשּׁוֹבֵר בַּטָּמֵא — אֵינוֹ לוֹקֶה אֶת הָאַרְבָּעִים.
Anything edible in a large ox —- must be eaten in a tender kid, including the ends of the shoulder blades and the cartilage.  [If] one breaks the bone of an uncontaminated pesach, he in-curs the penalty of forty [lashes]. But one who leaves over [flesh] of an uncontaminated one, or who breaks [a bone] of a contaminated one, does not incur the penalty of forty [lashes].