Tosefta for Pesachim 112:5
א"ל אין מוכן לאדם לא הוי מוכן לכלבים דכל מידי דחזי לאיניש לא מקצה ליה מדעתיה מוכן לעורבים הוי מוכן לאדם כל מידי דחזי לאיניש דעתיה עלויה
for man is not ready for dogs, for we learned, R'Judah said, If it was not nebelah from the eve of the Sabbath, it is forbidden, because it is not of that which is ready,<span class="x" onmousemove="('comment',' If an animal dies on the Sabbath, the first Tanna holds that the carcass may be cut up for dogs. But R. Judah rules as stated. For while alive it could have been ritually killed and then permitted for human consumption; hence it was ready not for dogs but for human beings, and thus R. Judah holds that its readiness for human beings does not make it ready for dogs too.');"><sup>7</sup></span> then shall what is ready for birds be [regarded as] ready for human beings?<span class="x" onmousemove="('comment',' Surely not!');"><sup>8</sup></span> - Yes, he replied.