Midrash for Chullin 229:17
שילוח הקן ליתסר
Should not 'It and its young' be forbidden, since I have declared it to be abominable to you?<span class="x" onmousemove="('comment',' Cf. Lev. ibid. 28. If the dam and its young were both slaughtered in one day, that which was slaughtered last should be forbidden for all time and for all use; nevertheless it is established law that even though the law has been transgressed both animals are permitted; v. supra 78a.');"><sup>11</sup></span>
Sifrei Devarim
(Devarim 14:6) "And every beast that has split hooves": Because we find that Scripture construed "treifah" ("torn" [in Shemoth 22:30 "and flesh in the field treifah you shall not eat"]) as "treifoth" (i.e., varieties of treifah that are forbidden to all [even non-priests]), I will also construe "pasul" (unfit) as "p'sulim" (i.e., unfit for eating for all), e.g., one's plowing with an ox and an ass (together), or with (animals dedicated as) offerings. It is, therefore, written (to include these as permitted to be eaten) "the ox, the lamb of sheep, and the kid of goats shall you eat."
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