Reference for Pesachim 167:3

<big><strong>מתני׳</strong></big> כל הנאכל בשור הגדול יאכל בגדי הרך וראשי כנפים והסחוסים:

<big><b>MISHNAH: </b></big>EVERYTHING WHICH CAN BE EATEN OF A FULL-GROWN OX MAY BE EATEN OF A TENDER GOAT,<span class="x" onmousemove="('comment',' But not those portions of a full-grown ox which are too hard to be eaten (the reference, of course, is to the Passover-offering) , though in the case of a young goat these are soft and edible.');">⁴</span> AND ALSO THE TOPS OF THE FORELEGS AND THE GRISTLES.<span class="x" onmousemove="('comment',' E.g., the cartilage of the ears, the gristly portion of the breast, and the small ribs at the end of the spine.');">⁵</span>

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